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1 /*
2  * Generic driver for the MPSC (UART mode) on Marvell parts (e.g., GT64240,
3  * GT64260, MV64340, MV64360, GT96100, ... ).
4  *
5  * Author: Mark A. Greer <mgreer@mvista.com>
6  *
7  * Based on an old MPSC driver that was in the linuxppc tree.  It appears to
8  * have been created by Chris Zankel (formerly of MontaVista) but there
9  * is no proper Copyright so I'm not sure.  Apparently, parts were also
10  * taken from PPCBoot (now U-Boot).  Also based on drivers/serial/8250.c
11  * by Russell King.
12  *
13  * 2004 (c) MontaVista, Software, Inc.  This file is licensed under
14  * the terms of the GNU General Public License version 2.  This program
15  * is licensed "as is" without any warranty of any kind, whether express
16  * or implied.
17  */
18 /*
19  * The MPSC interface is much like a typical network controller's interface.
20  * That is, you set up separate rings of descriptors for transmitting and
21  * receiving data.  There is also a pool of buffers with (one buffer per
22  * descriptor) that incoming data are dma'd into or outgoing data are dma'd
23  * out of.
24  *
25  * The MPSC requires two other controllers to be able to work.  The Baud Rate
26  * Generator (BRG) provides a clock at programmable frequencies which determines
27  * the baud rate.  The Serial DMA Controller (SDMA) takes incoming data from the
28  * MPSC and DMA's it into memory or DMA's outgoing data and passes it to the
29  * MPSC.  It is actually the SDMA interrupt that the driver uses to keep the
30  * transmit and receive "engines" going (i.e., indicate data has been
31  * transmitted or received).
32  *
33  * NOTES:
34  *
35  * 1) Some chips have an erratum where several regs cannot be
36  * read.  To work around that, we keep a local copy of those regs in
37  * 'mpsc_port_info'.
38  *
39  * 2) Some chips have an erratum where the ctlr will hang when the SDMA ctlr
40  * accesses system mem with coherency enabled.  For that reason, the driver
41  * assumes that coherency for that ctlr has been disabled.  This means
42  * that when in a cache coherent system, the driver has to manually manage
43  * the data cache on the areas that it touches because the dma_* macro are
44  * basically no-ops.
45  *
46  * 3) There is an erratum (on PPC) where you can't use the instruction to do
47  * a DMA_TO_DEVICE/cache clean so DMA_BIDIRECTIONAL/flushes are used in places
48  * where a DMA_TO_DEVICE/clean would have [otherwise] sufficed.
49  *
50  * 4) AFAICT, hardware flow control isn't supported by the controller --MAG.
51  */
52 
53 
54 #if defined(CONFIG_SERIAL_MPSC_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
55 #define SUPPORT_SYSRQ
56 #endif
57 
58 #include <linux/tty.h>
59 #include <linux/tty_flip.h>
60 #include <linux/ioport.h>
61 #include <linux/init.h>
62 #include <linux/console.h>
63 #include <linux/sysrq.h>
64 #include <linux/serial.h>
65 #include <linux/serial_core.h>
66 #include <linux/delay.h>
67 #include <linux/device.h>
68 #include <linux/dma-mapping.h>
69 #include <linux/mv643xx.h>
70 #include <linux/platform_device.h>
71 #include <linux/gfp.h>
72 
73 #include <asm/io.h>
74 #include <asm/irq.h>
75 
76 #define	MPSC_NUM_CTLRS		2
77 
78 /*
79  * Descriptors and buffers must be cache line aligned.
80  * Buffers lengths must be multiple of cache line size.
81  * Number of Tx & Rx descriptors must be powers of 2.
82  */
83 #define	MPSC_RXR_ENTRIES	32
84 #define	MPSC_RXRE_SIZE		dma_get_cache_alignment()
85 #define	MPSC_RXR_SIZE		(MPSC_RXR_ENTRIES * MPSC_RXRE_SIZE)
86 #define	MPSC_RXBE_SIZE		dma_get_cache_alignment()
87 #define	MPSC_RXB_SIZE		(MPSC_RXR_ENTRIES * MPSC_RXBE_SIZE)
88 
89 #define	MPSC_TXR_ENTRIES	32
90 #define	MPSC_TXRE_SIZE		dma_get_cache_alignment()
91 #define	MPSC_TXR_SIZE		(MPSC_TXR_ENTRIES * MPSC_TXRE_SIZE)
92 #define	MPSC_TXBE_SIZE		dma_get_cache_alignment()
93 #define	MPSC_TXB_SIZE		(MPSC_TXR_ENTRIES * MPSC_TXBE_SIZE)
94 
95 #define	MPSC_DMA_ALLOC_SIZE	(MPSC_RXR_SIZE + MPSC_RXB_SIZE + MPSC_TXR_SIZE \
96 		+ MPSC_TXB_SIZE + dma_get_cache_alignment() /* for alignment */)
97 
98 /* Rx and Tx Ring entry descriptors -- assume entry size is <= cacheline size */
99 struct mpsc_rx_desc {
100 	u16 bufsize;
101 	u16 bytecnt;
102 	u32 cmdstat;
103 	u32 link;
104 	u32 buf_ptr;
105 } __attribute((packed));
106 
107 struct mpsc_tx_desc {
108 	u16 bytecnt;
109 	u16 shadow;
110 	u32 cmdstat;
111 	u32 link;
112 	u32 buf_ptr;
113 } __attribute((packed));
114 
115 /*
116  * Some regs that have the erratum that you can't read them are are shared
117  * between the two MPSC controllers.  This struct contains those shared regs.
118  */
119 struct mpsc_shared_regs {
120 	phys_addr_t mpsc_routing_base_p;
121 	phys_addr_t sdma_intr_base_p;
122 
123 	void __iomem *mpsc_routing_base;
124 	void __iomem *sdma_intr_base;
125 
126 	u32 MPSC_MRR_m;
127 	u32 MPSC_RCRR_m;
128 	u32 MPSC_TCRR_m;
129 	u32 SDMA_INTR_CAUSE_m;
130 	u32 SDMA_INTR_MASK_m;
131 };
132 
133 /* The main driver data structure */
134 struct mpsc_port_info {
135 	struct uart_port port;	/* Overlay uart_port structure */
136 
137 	/* Internal driver state for this ctlr */
138 	u8 ready;
139 	u8 rcv_data;
140 
141 	/* Info passed in from platform */
142 	u8 mirror_regs;		/* Need to mirror regs? */
143 	u8 cache_mgmt;		/* Need manual cache mgmt? */
144 	u8 brg_can_tune;	/* BRG has baud tuning? */
145 	u32 brg_clk_src;
146 	u16 mpsc_max_idle;
147 	int default_baud;
148 	int default_bits;
149 	int default_parity;
150 	int default_flow;
151 
152 	/* Physical addresses of various blocks of registers (from platform) */
153 	phys_addr_t mpsc_base_p;
154 	phys_addr_t sdma_base_p;
155 	phys_addr_t brg_base_p;
156 
157 	/* Virtual addresses of various blocks of registers (from platform) */
158 	void __iomem *mpsc_base;
159 	void __iomem *sdma_base;
160 	void __iomem *brg_base;
161 
162 	/* Descriptor ring and buffer allocations */
163 	void *dma_region;
164 	dma_addr_t dma_region_p;
165 
166 	dma_addr_t rxr;		/* Rx descriptor ring */
167 	dma_addr_t rxr_p;	/* Phys addr of rxr */
168 	u8 *rxb;		/* Rx Ring I/O buf */
169 	u8 *rxb_p;		/* Phys addr of rxb */
170 	u32 rxr_posn;		/* First desc w/ Rx data */
171 
172 	dma_addr_t txr;		/* Tx descriptor ring */
173 	dma_addr_t txr_p;	/* Phys addr of txr */
174 	u8 *txb;		/* Tx Ring I/O buf */
175 	u8 *txb_p;		/* Phys addr of txb */
176 	int txr_head;		/* Where new data goes */
177 	int txr_tail;		/* Where sent data comes off */
178 	spinlock_t tx_lock;	/* transmit lock */
179 
180 	/* Mirrored values of regs we can't read (if 'mirror_regs' set) */
181 	u32 MPSC_MPCR_m;
182 	u32 MPSC_CHR_1_m;
183 	u32 MPSC_CHR_2_m;
184 	u32 MPSC_CHR_10_m;
185 	u32 BRG_BCR_m;
186 	struct mpsc_shared_regs *shared_regs;
187 };
188 
189 /* Hooks to platform-specific code */
190 int mpsc_platform_register_driver(void);
191 void mpsc_platform_unregister_driver(void);
192 
193 /* Hooks back in to mpsc common to be called by platform-specific code */
194 struct mpsc_port_info *mpsc_device_probe(int index);
195 struct mpsc_port_info *mpsc_device_remove(int index);
196 
197 /* Main MPSC Configuration Register Offsets */
198 #define	MPSC_MMCRL			0x0000
199 #define	MPSC_MMCRH			0x0004
200 #define	MPSC_MPCR			0x0008
201 #define	MPSC_CHR_1			0x000c
202 #define	MPSC_CHR_2			0x0010
203 #define	MPSC_CHR_3			0x0014
204 #define	MPSC_CHR_4			0x0018
205 #define	MPSC_CHR_5			0x001c
206 #define	MPSC_CHR_6			0x0020
207 #define	MPSC_CHR_7			0x0024
208 #define	MPSC_CHR_8			0x0028
209 #define	MPSC_CHR_9			0x002c
210 #define	MPSC_CHR_10			0x0030
211 #define	MPSC_CHR_11			0x0034
212 
213 #define	MPSC_MPCR_FRZ			(1 << 9)
214 #define	MPSC_MPCR_CL_5			0
215 #define	MPSC_MPCR_CL_6			1
216 #define	MPSC_MPCR_CL_7			2
217 #define	MPSC_MPCR_CL_8			3
218 #define	MPSC_MPCR_SBL_1			0
219 #define	MPSC_MPCR_SBL_2			1
220 
221 #define	MPSC_CHR_2_TEV			(1<<1)
222 #define	MPSC_CHR_2_TA			(1<<7)
223 #define	MPSC_CHR_2_TTCS			(1<<9)
224 #define	MPSC_CHR_2_REV			(1<<17)
225 #define	MPSC_CHR_2_RA			(1<<23)
226 #define	MPSC_CHR_2_CRD			(1<<25)
227 #define	MPSC_CHR_2_EH			(1<<31)
228 #define	MPSC_CHR_2_PAR_ODD		0
229 #define	MPSC_CHR_2_PAR_SPACE		1
230 #define	MPSC_CHR_2_PAR_EVEN		2
231 #define	MPSC_CHR_2_PAR_MARK		3
232 
233 /* MPSC Signal Routing */
234 #define	MPSC_MRR			0x0000
235 #define	MPSC_RCRR			0x0004
236 #define	MPSC_TCRR			0x0008
237 
238 /* Serial DMA Controller Interface Registers */
239 #define	SDMA_SDC			0x0000
240 #define	SDMA_SDCM			0x0008
241 #define	SDMA_RX_DESC			0x0800
242 #define	SDMA_RX_BUF_PTR			0x0808
243 #define	SDMA_SCRDP			0x0810
244 #define	SDMA_TX_DESC			0x0c00
245 #define	SDMA_SCTDP			0x0c10
246 #define	SDMA_SFTDP			0x0c14
247 
248 #define	SDMA_DESC_CMDSTAT_PE		(1<<0)
249 #define	SDMA_DESC_CMDSTAT_CDL		(1<<1)
250 #define	SDMA_DESC_CMDSTAT_FR		(1<<3)
251 #define	SDMA_DESC_CMDSTAT_OR		(1<<6)
252 #define	SDMA_DESC_CMDSTAT_BR		(1<<9)
253 #define	SDMA_DESC_CMDSTAT_MI		(1<<10)
254 #define	SDMA_DESC_CMDSTAT_A		(1<<11)
255 #define	SDMA_DESC_CMDSTAT_AM		(1<<12)
256 #define	SDMA_DESC_CMDSTAT_CT		(1<<13)
257 #define	SDMA_DESC_CMDSTAT_C		(1<<14)
258 #define	SDMA_DESC_CMDSTAT_ES		(1<<15)
259 #define	SDMA_DESC_CMDSTAT_L		(1<<16)
260 #define	SDMA_DESC_CMDSTAT_F		(1<<17)
261 #define	SDMA_DESC_CMDSTAT_P		(1<<18)
262 #define	SDMA_DESC_CMDSTAT_EI		(1<<23)
263 #define	SDMA_DESC_CMDSTAT_O		(1<<31)
264 
265 #define SDMA_DESC_DFLT			(SDMA_DESC_CMDSTAT_O \
266 		| SDMA_DESC_CMDSTAT_EI)
267 
268 #define	SDMA_SDC_RFT			(1<<0)
269 #define	SDMA_SDC_SFM			(1<<1)
270 #define	SDMA_SDC_BLMR			(1<<6)
271 #define	SDMA_SDC_BLMT			(1<<7)
272 #define	SDMA_SDC_POVR			(1<<8)
273 #define	SDMA_SDC_RIFB			(1<<9)
274 
275 #define	SDMA_SDCM_ERD			(1<<7)
276 #define	SDMA_SDCM_AR			(1<<15)
277 #define	SDMA_SDCM_STD			(1<<16)
278 #define	SDMA_SDCM_TXD			(1<<23)
279 #define	SDMA_SDCM_AT			(1<<31)
280 
281 #define	SDMA_0_CAUSE_RXBUF		(1<<0)
282 #define	SDMA_0_CAUSE_RXERR		(1<<1)
283 #define	SDMA_0_CAUSE_TXBUF		(1<<2)
284 #define	SDMA_0_CAUSE_TXEND		(1<<3)
285 #define	SDMA_1_CAUSE_RXBUF		(1<<8)
286 #define	SDMA_1_CAUSE_RXERR		(1<<9)
287 #define	SDMA_1_CAUSE_TXBUF		(1<<10)
288 #define	SDMA_1_CAUSE_TXEND		(1<<11)
289 
290 #define	SDMA_CAUSE_RX_MASK	(SDMA_0_CAUSE_RXBUF | SDMA_0_CAUSE_RXERR \
291 		| SDMA_1_CAUSE_RXBUF | SDMA_1_CAUSE_RXERR)
292 #define	SDMA_CAUSE_TX_MASK	(SDMA_0_CAUSE_TXBUF | SDMA_0_CAUSE_TXEND \
293 		| SDMA_1_CAUSE_TXBUF | SDMA_1_CAUSE_TXEND)
294 
295 /* SDMA Interrupt registers */
296 #define	SDMA_INTR_CAUSE			0x0000
297 #define	SDMA_INTR_MASK			0x0080
298 
299 /* Baud Rate Generator Interface Registers */
300 #define	BRG_BCR				0x0000
301 #define	BRG_BTR				0x0004
302 
303 /*
304  * Define how this driver is known to the outside (we've been assigned a
305  * range on the "Low-density serial ports" major).
306  */
307 #define MPSC_MAJOR			204
308 #define MPSC_MINOR_START		44
309 #define	MPSC_DRIVER_NAME		"MPSC"
310 #define	MPSC_DEV_NAME			"ttyMM"
311 #define	MPSC_VERSION			"1.00"
312 
313 static struct mpsc_port_info mpsc_ports[MPSC_NUM_CTLRS];
314 static struct mpsc_shared_regs mpsc_shared_regs;
315 static struct uart_driver mpsc_reg;
316 
317 static void mpsc_start_rx(struct mpsc_port_info *pi);
318 static void mpsc_free_ring_mem(struct mpsc_port_info *pi);
319 static void mpsc_release_port(struct uart_port *port);
320 /*
321  ******************************************************************************
322  *
323  * Baud Rate Generator Routines (BRG)
324  *
325  ******************************************************************************
326  */
mpsc_brg_init(struct mpsc_port_info * pi,u32 clk_src)327 static void mpsc_brg_init(struct mpsc_port_info *pi, u32 clk_src)
328 {
329 	u32	v;
330 
331 	v = (pi->mirror_regs) ? pi->BRG_BCR_m : readl(pi->brg_base + BRG_BCR);
332 	v = (v & ~(0xf << 18)) | ((clk_src & 0xf) << 18);
333 
334 	if (pi->brg_can_tune)
335 		v &= ~(1 << 25);
336 
337 	if (pi->mirror_regs)
338 		pi->BRG_BCR_m = v;
339 	writel(v, pi->brg_base + BRG_BCR);
340 
341 	writel(readl(pi->brg_base + BRG_BTR) & 0xffff0000,
342 		pi->brg_base + BRG_BTR);
343 }
344 
mpsc_brg_enable(struct mpsc_port_info * pi)345 static void mpsc_brg_enable(struct mpsc_port_info *pi)
346 {
347 	u32	v;
348 
349 	v = (pi->mirror_regs) ? pi->BRG_BCR_m : readl(pi->brg_base + BRG_BCR);
350 	v |= (1 << 16);
351 
352 	if (pi->mirror_regs)
353 		pi->BRG_BCR_m = v;
354 	writel(v, pi->brg_base + BRG_BCR);
355 }
356 
mpsc_brg_disable(struct mpsc_port_info * pi)357 static void mpsc_brg_disable(struct mpsc_port_info *pi)
358 {
359 	u32	v;
360 
361 	v = (pi->mirror_regs) ? pi->BRG_BCR_m : readl(pi->brg_base + BRG_BCR);
362 	v &= ~(1 << 16);
363 
364 	if (pi->mirror_regs)
365 		pi->BRG_BCR_m = v;
366 	writel(v, pi->brg_base + BRG_BCR);
367 }
368 
369 /*
370  * To set the baud, we adjust the CDV field in the BRG_BCR reg.
371  * From manual: Baud = clk / ((CDV+1)*2) ==> CDV = (clk / (baud*2)) - 1.
372  * However, the input clock is divided by 16 in the MPSC b/c of how
373  * 'MPSC_MMCRH' was set up so we have to divide the 'clk' used in our
374  * calculation by 16 to account for that.  So the real calculation
375  * that accounts for the way the mpsc is set up is:
376  * CDV = (clk / (baud*2*16)) - 1 ==> CDV = (clk / (baud << 5)) - 1.
377  */
mpsc_set_baudrate(struct mpsc_port_info * pi,u32 baud)378 static void mpsc_set_baudrate(struct mpsc_port_info *pi, u32 baud)
379 {
380 	u32	cdv = (pi->port.uartclk / (baud << 5)) - 1;
381 	u32	v;
382 
383 	mpsc_brg_disable(pi);
384 	v = (pi->mirror_regs) ? pi->BRG_BCR_m : readl(pi->brg_base + BRG_BCR);
385 	v = (v & 0xffff0000) | (cdv & 0xffff);
386 
387 	if (pi->mirror_regs)
388 		pi->BRG_BCR_m = v;
389 	writel(v, pi->brg_base + BRG_BCR);
390 	mpsc_brg_enable(pi);
391 }
392 
393 /*
394  ******************************************************************************
395  *
396  * Serial DMA Routines (SDMA)
397  *
398  ******************************************************************************
399  */
400 
mpsc_sdma_burstsize(struct mpsc_port_info * pi,u32 burst_size)401 static void mpsc_sdma_burstsize(struct mpsc_port_info *pi, u32 burst_size)
402 {
403 	u32	v;
404 
405 	pr_debug("mpsc_sdma_burstsize[%d]: burst_size: %d\n",
406 			pi->port.line, burst_size);
407 
408 	burst_size >>= 3; /* Divide by 8 b/c reg values are 8-byte chunks */
409 
410 	if (burst_size < 2)
411 		v = 0x0;	/* 1 64-bit word */
412 	else if (burst_size < 4)
413 		v = 0x1;	/* 2 64-bit words */
414 	else if (burst_size < 8)
415 		v = 0x2;	/* 4 64-bit words */
416 	else
417 		v = 0x3;	/* 8 64-bit words */
418 
419 	writel((readl(pi->sdma_base + SDMA_SDC) & (0x3 << 12)) | (v << 12),
420 		pi->sdma_base + SDMA_SDC);
421 }
422 
mpsc_sdma_init(struct mpsc_port_info * pi,u32 burst_size)423 static void mpsc_sdma_init(struct mpsc_port_info *pi, u32 burst_size)
424 {
425 	pr_debug("mpsc_sdma_init[%d]: burst_size: %d\n", pi->port.line,
426 		burst_size);
427 
428 	writel((readl(pi->sdma_base + SDMA_SDC) & 0x3ff) | 0x03f,
429 		pi->sdma_base + SDMA_SDC);
430 	mpsc_sdma_burstsize(pi, burst_size);
431 }
432 
mpsc_sdma_intr_mask(struct mpsc_port_info * pi,u32 mask)433 static u32 mpsc_sdma_intr_mask(struct mpsc_port_info *pi, u32 mask)
434 {
435 	u32	old, v;
436 
437 	pr_debug("mpsc_sdma_intr_mask[%d]: mask: 0x%x\n", pi->port.line, mask);
438 
439 	old = v = (pi->mirror_regs) ? pi->shared_regs->SDMA_INTR_MASK_m :
440 		readl(pi->shared_regs->sdma_intr_base + SDMA_INTR_MASK);
441 
442 	mask &= 0xf;
443 	if (pi->port.line)
444 		mask <<= 8;
445 	v &= ~mask;
446 
447 	if (pi->mirror_regs)
448 		pi->shared_regs->SDMA_INTR_MASK_m = v;
449 	writel(v, pi->shared_regs->sdma_intr_base + SDMA_INTR_MASK);
450 
451 	if (pi->port.line)
452 		old >>= 8;
453 	return old & 0xf;
454 }
455 
mpsc_sdma_intr_unmask(struct mpsc_port_info * pi,u32 mask)456 static void mpsc_sdma_intr_unmask(struct mpsc_port_info *pi, u32 mask)
457 {
458 	u32	v;
459 
460 	pr_debug("mpsc_sdma_intr_unmask[%d]: mask: 0x%x\n", pi->port.line,mask);
461 
462 	v = (pi->mirror_regs) ? pi->shared_regs->SDMA_INTR_MASK_m
463 		: readl(pi->shared_regs->sdma_intr_base + SDMA_INTR_MASK);
464 
465 	mask &= 0xf;
466 	if (pi->port.line)
467 		mask <<= 8;
468 	v |= mask;
469 
470 	if (pi->mirror_regs)
471 		pi->shared_regs->SDMA_INTR_MASK_m = v;
472 	writel(v, pi->shared_regs->sdma_intr_base + SDMA_INTR_MASK);
473 }
474 
mpsc_sdma_intr_ack(struct mpsc_port_info * pi)475 static void mpsc_sdma_intr_ack(struct mpsc_port_info *pi)
476 {
477 	pr_debug("mpsc_sdma_intr_ack[%d]: Acknowledging IRQ\n", pi->port.line);
478 
479 	if (pi->mirror_regs)
480 		pi->shared_regs->SDMA_INTR_CAUSE_m = 0;
481 	writeb(0x00, pi->shared_regs->sdma_intr_base + SDMA_INTR_CAUSE
482 			+ pi->port.line);
483 }
484 
mpsc_sdma_set_rx_ring(struct mpsc_port_info * pi,struct mpsc_rx_desc * rxre_p)485 static void mpsc_sdma_set_rx_ring(struct mpsc_port_info *pi,
486 		struct mpsc_rx_desc *rxre_p)
487 {
488 	pr_debug("mpsc_sdma_set_rx_ring[%d]: rxre_p: 0x%x\n",
489 		pi->port.line, (u32)rxre_p);
490 
491 	writel((u32)rxre_p, pi->sdma_base + SDMA_SCRDP);
492 }
493 
mpsc_sdma_set_tx_ring(struct mpsc_port_info * pi,struct mpsc_tx_desc * txre_p)494 static void mpsc_sdma_set_tx_ring(struct mpsc_port_info *pi,
495 		struct mpsc_tx_desc *txre_p)
496 {
497 	writel((u32)txre_p, pi->sdma_base + SDMA_SFTDP);
498 	writel((u32)txre_p, pi->sdma_base + SDMA_SCTDP);
499 }
500 
mpsc_sdma_cmd(struct mpsc_port_info * pi,u32 val)501 static void mpsc_sdma_cmd(struct mpsc_port_info *pi, u32 val)
502 {
503 	u32	v;
504 
505 	v = readl(pi->sdma_base + SDMA_SDCM);
506 	if (val)
507 		v |= val;
508 	else
509 		v = 0;
510 	wmb();
511 	writel(v, pi->sdma_base + SDMA_SDCM);
512 	wmb();
513 }
514 
mpsc_sdma_tx_active(struct mpsc_port_info * pi)515 static uint mpsc_sdma_tx_active(struct mpsc_port_info *pi)
516 {
517 	return readl(pi->sdma_base + SDMA_SDCM) & SDMA_SDCM_TXD;
518 }
519 
mpsc_sdma_start_tx(struct mpsc_port_info * pi)520 static void mpsc_sdma_start_tx(struct mpsc_port_info *pi)
521 {
522 	struct mpsc_tx_desc *txre, *txre_p;
523 
524 	/* If tx isn't running & there's a desc ready to go, start it */
525 	if (!mpsc_sdma_tx_active(pi)) {
526 		txre = (struct mpsc_tx_desc *)(pi->txr
527 				+ (pi->txr_tail * MPSC_TXRE_SIZE));
528 		dma_cache_sync(pi->port.dev, (void *)txre, MPSC_TXRE_SIZE,
529 				DMA_FROM_DEVICE);
530 #if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
531 		if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
532 			invalidate_dcache_range((ulong)txre,
533 					(ulong)txre + MPSC_TXRE_SIZE);
534 #endif
535 
536 		if (be32_to_cpu(txre->cmdstat) & SDMA_DESC_CMDSTAT_O) {
537 			txre_p = (struct mpsc_tx_desc *)
538 				(pi->txr_p + (pi->txr_tail * MPSC_TXRE_SIZE));
539 
540 			mpsc_sdma_set_tx_ring(pi, txre_p);
541 			mpsc_sdma_cmd(pi, SDMA_SDCM_STD | SDMA_SDCM_TXD);
542 		}
543 	}
544 }
545 
mpsc_sdma_stop(struct mpsc_port_info * pi)546 static void mpsc_sdma_stop(struct mpsc_port_info *pi)
547 {
548 	pr_debug("mpsc_sdma_stop[%d]: Stopping SDMA\n", pi->port.line);
549 
550 	/* Abort any SDMA transfers */
551 	mpsc_sdma_cmd(pi, 0);
552 	mpsc_sdma_cmd(pi, SDMA_SDCM_AR | SDMA_SDCM_AT);
553 
554 	/* Clear the SDMA current and first TX and RX pointers */
555 	mpsc_sdma_set_tx_ring(pi, NULL);
556 	mpsc_sdma_set_rx_ring(pi, NULL);
557 
558 	/* Disable interrupts */
559 	mpsc_sdma_intr_mask(pi, 0xf);
560 	mpsc_sdma_intr_ack(pi);
561 }
562 
563 /*
564  ******************************************************************************
565  *
566  * Multi-Protocol Serial Controller Routines (MPSC)
567  *
568  ******************************************************************************
569  */
570 
mpsc_hw_init(struct mpsc_port_info * pi)571 static void mpsc_hw_init(struct mpsc_port_info *pi)
572 {
573 	u32	v;
574 
575 	pr_debug("mpsc_hw_init[%d]: Initializing hardware\n", pi->port.line);
576 
577 	/* Set up clock routing */
578 	if (pi->mirror_regs) {
579 		v = pi->shared_regs->MPSC_MRR_m;
580 		v &= ~0x1c7;
581 		pi->shared_regs->MPSC_MRR_m = v;
582 		writel(v, pi->shared_regs->mpsc_routing_base + MPSC_MRR);
583 
584 		v = pi->shared_regs->MPSC_RCRR_m;
585 		v = (v & ~0xf0f) | 0x100;
586 		pi->shared_regs->MPSC_RCRR_m = v;
587 		writel(v, pi->shared_regs->mpsc_routing_base + MPSC_RCRR);
588 
589 		v = pi->shared_regs->MPSC_TCRR_m;
590 		v = (v & ~0xf0f) | 0x100;
591 		pi->shared_regs->MPSC_TCRR_m = v;
592 		writel(v, pi->shared_regs->mpsc_routing_base + MPSC_TCRR);
593 	} else {
594 		v = readl(pi->shared_regs->mpsc_routing_base + MPSC_MRR);
595 		v &= ~0x1c7;
596 		writel(v, pi->shared_regs->mpsc_routing_base + MPSC_MRR);
597 
598 		v = readl(pi->shared_regs->mpsc_routing_base + MPSC_RCRR);
599 		v = (v & ~0xf0f) | 0x100;
600 		writel(v, pi->shared_regs->mpsc_routing_base + MPSC_RCRR);
601 
602 		v = readl(pi->shared_regs->mpsc_routing_base + MPSC_TCRR);
603 		v = (v & ~0xf0f) | 0x100;
604 		writel(v, pi->shared_regs->mpsc_routing_base + MPSC_TCRR);
605 	}
606 
607 	/* Put MPSC in UART mode & enabel Tx/Rx egines */
608 	writel(0x000004c4, pi->mpsc_base + MPSC_MMCRL);
609 
610 	/* No preamble, 16x divider, low-latency, */
611 	writel(0x04400400, pi->mpsc_base + MPSC_MMCRH);
612 	mpsc_set_baudrate(pi, pi->default_baud);
613 
614 	if (pi->mirror_regs) {
615 		pi->MPSC_CHR_1_m = 0;
616 		pi->MPSC_CHR_2_m = 0;
617 	}
618 	writel(0, pi->mpsc_base + MPSC_CHR_1);
619 	writel(0, pi->mpsc_base + MPSC_CHR_2);
620 	writel(pi->mpsc_max_idle, pi->mpsc_base + MPSC_CHR_3);
621 	writel(0, pi->mpsc_base + MPSC_CHR_4);
622 	writel(0, pi->mpsc_base + MPSC_CHR_5);
623 	writel(0, pi->mpsc_base + MPSC_CHR_6);
624 	writel(0, pi->mpsc_base + MPSC_CHR_7);
625 	writel(0, pi->mpsc_base + MPSC_CHR_8);
626 	writel(0, pi->mpsc_base + MPSC_CHR_9);
627 	writel(0, pi->mpsc_base + MPSC_CHR_10);
628 }
629 
mpsc_enter_hunt(struct mpsc_port_info * pi)630 static void mpsc_enter_hunt(struct mpsc_port_info *pi)
631 {
632 	pr_debug("mpsc_enter_hunt[%d]: Hunting...\n", pi->port.line);
633 
634 	if (pi->mirror_regs) {
635 		writel(pi->MPSC_CHR_2_m | MPSC_CHR_2_EH,
636 			pi->mpsc_base + MPSC_CHR_2);
637 		/* Erratum prevents reading CHR_2 so just delay for a while */
638 		udelay(100);
639 	} else {
640 		writel(readl(pi->mpsc_base + MPSC_CHR_2) | MPSC_CHR_2_EH,
641 				pi->mpsc_base + MPSC_CHR_2);
642 
643 		while (readl(pi->mpsc_base + MPSC_CHR_2) & MPSC_CHR_2_EH)
644 			udelay(10);
645 	}
646 }
647 
mpsc_freeze(struct mpsc_port_info * pi)648 static void mpsc_freeze(struct mpsc_port_info *pi)
649 {
650 	u32	v;
651 
652 	pr_debug("mpsc_freeze[%d]: Freezing\n", pi->port.line);
653 
654 	v = (pi->mirror_regs) ? pi->MPSC_MPCR_m :
655 		readl(pi->mpsc_base + MPSC_MPCR);
656 	v |= MPSC_MPCR_FRZ;
657 
658 	if (pi->mirror_regs)
659 		pi->MPSC_MPCR_m = v;
660 	writel(v, pi->mpsc_base + MPSC_MPCR);
661 }
662 
mpsc_unfreeze(struct mpsc_port_info * pi)663 static void mpsc_unfreeze(struct mpsc_port_info *pi)
664 {
665 	u32	v;
666 
667 	v = (pi->mirror_regs) ? pi->MPSC_MPCR_m :
668 		readl(pi->mpsc_base + MPSC_MPCR);
669 	v &= ~MPSC_MPCR_FRZ;
670 
671 	if (pi->mirror_regs)
672 		pi->MPSC_MPCR_m = v;
673 	writel(v, pi->mpsc_base + MPSC_MPCR);
674 
675 	pr_debug("mpsc_unfreeze[%d]: Unfrozen\n", pi->port.line);
676 }
677 
mpsc_set_char_length(struct mpsc_port_info * pi,u32 len)678 static void mpsc_set_char_length(struct mpsc_port_info *pi, u32 len)
679 {
680 	u32	v;
681 
682 	pr_debug("mpsc_set_char_length[%d]: char len: %d\n", pi->port.line,len);
683 
684 	v = (pi->mirror_regs) ? pi->MPSC_MPCR_m :
685 		readl(pi->mpsc_base + MPSC_MPCR);
686 	v = (v & ~(0x3 << 12)) | ((len & 0x3) << 12);
687 
688 	if (pi->mirror_regs)
689 		pi->MPSC_MPCR_m = v;
690 	writel(v, pi->mpsc_base + MPSC_MPCR);
691 }
692 
mpsc_set_stop_bit_length(struct mpsc_port_info * pi,u32 len)693 static void mpsc_set_stop_bit_length(struct mpsc_port_info *pi, u32 len)
694 {
695 	u32	v;
696 
697 	pr_debug("mpsc_set_stop_bit_length[%d]: stop bits: %d\n",
698 		pi->port.line, len);
699 
700 	v = (pi->mirror_regs) ? pi->MPSC_MPCR_m :
701 		readl(pi->mpsc_base + MPSC_MPCR);
702 
703 	v = (v & ~(1 << 14)) | ((len & 0x1) << 14);
704 
705 	if (pi->mirror_regs)
706 		pi->MPSC_MPCR_m = v;
707 	writel(v, pi->mpsc_base + MPSC_MPCR);
708 }
709 
mpsc_set_parity(struct mpsc_port_info * pi,u32 p)710 static void mpsc_set_parity(struct mpsc_port_info *pi, u32 p)
711 {
712 	u32	v;
713 
714 	pr_debug("mpsc_set_parity[%d]: parity bits: 0x%x\n", pi->port.line, p);
715 
716 	v = (pi->mirror_regs) ? pi->MPSC_CHR_2_m :
717 		readl(pi->mpsc_base + MPSC_CHR_2);
718 
719 	p &= 0x3;
720 	v = (v & ~0xc000c) | (p << 18) | (p << 2);
721 
722 	if (pi->mirror_regs)
723 		pi->MPSC_CHR_2_m = v;
724 	writel(v, pi->mpsc_base + MPSC_CHR_2);
725 }
726 
727 /*
728  ******************************************************************************
729  *
730  * Driver Init Routines
731  *
732  ******************************************************************************
733  */
734 
mpsc_init_hw(struct mpsc_port_info * pi)735 static void mpsc_init_hw(struct mpsc_port_info *pi)
736 {
737 	pr_debug("mpsc_init_hw[%d]: Initializing\n", pi->port.line);
738 
739 	mpsc_brg_init(pi, pi->brg_clk_src);
740 	mpsc_brg_enable(pi);
741 	mpsc_sdma_init(pi, dma_get_cache_alignment());	/* burst a cacheline */
742 	mpsc_sdma_stop(pi);
743 	mpsc_hw_init(pi);
744 }
745 
mpsc_alloc_ring_mem(struct mpsc_port_info * pi)746 static int mpsc_alloc_ring_mem(struct mpsc_port_info *pi)
747 {
748 	int rc = 0;
749 
750 	pr_debug("mpsc_alloc_ring_mem[%d]: Allocating ring mem\n",
751 		pi->port.line);
752 
753 	if (!pi->dma_region) {
754 		if (!dma_set_mask(pi->port.dev, 0xffffffff)) {
755 			printk(KERN_ERR "MPSC: Inadequate DMA support\n");
756 			rc = -ENXIO;
757 		} else if ((pi->dma_region = dma_alloc_attrs(pi->port.dev,
758 						MPSC_DMA_ALLOC_SIZE,
759 						&pi->dma_region_p, GFP_KERNEL,
760 						DMA_ATTR_NON_CONSISTENT))
761 				== NULL) {
762 			printk(KERN_ERR "MPSC: Can't alloc Desc region\n");
763 			rc = -ENOMEM;
764 		}
765 	}
766 
767 	return rc;
768 }
769 
mpsc_free_ring_mem(struct mpsc_port_info * pi)770 static void mpsc_free_ring_mem(struct mpsc_port_info *pi)
771 {
772 	pr_debug("mpsc_free_ring_mem[%d]: Freeing ring mem\n", pi->port.line);
773 
774 	if (pi->dma_region) {
775 		dma_free_attrs(pi->port.dev, MPSC_DMA_ALLOC_SIZE,
776 				pi->dma_region, pi->dma_region_p,
777 				DMA_ATTR_NON_CONSISTENT);
778 		pi->dma_region = NULL;
779 		pi->dma_region_p = (dma_addr_t)NULL;
780 	}
781 }
782 
mpsc_init_rings(struct mpsc_port_info * pi)783 static void mpsc_init_rings(struct mpsc_port_info *pi)
784 {
785 	struct mpsc_rx_desc *rxre;
786 	struct mpsc_tx_desc *txre;
787 	dma_addr_t dp, dp_p;
788 	u8 *bp, *bp_p;
789 	int i;
790 
791 	pr_debug("mpsc_init_rings[%d]: Initializing rings\n", pi->port.line);
792 
793 	BUG_ON(pi->dma_region == NULL);
794 
795 	memset(pi->dma_region, 0, MPSC_DMA_ALLOC_SIZE);
796 
797 	/*
798 	 * Descriptors & buffers are multiples of cacheline size and must be
799 	 * cacheline aligned.
800 	 */
801 	dp = ALIGN((u32)pi->dma_region, dma_get_cache_alignment());
802 	dp_p = ALIGN((u32)pi->dma_region_p, dma_get_cache_alignment());
803 
804 	/*
805 	 * Partition dma region into rx ring descriptor, rx buffers,
806 	 * tx ring descriptors, and tx buffers.
807 	 */
808 	pi->rxr = dp;
809 	pi->rxr_p = dp_p;
810 	dp += MPSC_RXR_SIZE;
811 	dp_p += MPSC_RXR_SIZE;
812 
813 	pi->rxb = (u8 *)dp;
814 	pi->rxb_p = (u8 *)dp_p;
815 	dp += MPSC_RXB_SIZE;
816 	dp_p += MPSC_RXB_SIZE;
817 
818 	pi->rxr_posn = 0;
819 
820 	pi->txr = dp;
821 	pi->txr_p = dp_p;
822 	dp += MPSC_TXR_SIZE;
823 	dp_p += MPSC_TXR_SIZE;
824 
825 	pi->txb = (u8 *)dp;
826 	pi->txb_p = (u8 *)dp_p;
827 
828 	pi->txr_head = 0;
829 	pi->txr_tail = 0;
830 
831 	/* Init rx ring descriptors */
832 	dp = pi->rxr;
833 	dp_p = pi->rxr_p;
834 	bp = pi->rxb;
835 	bp_p = pi->rxb_p;
836 
837 	for (i = 0; i < MPSC_RXR_ENTRIES; i++) {
838 		rxre = (struct mpsc_rx_desc *)dp;
839 
840 		rxre->bufsize = cpu_to_be16(MPSC_RXBE_SIZE);
841 		rxre->bytecnt = cpu_to_be16(0);
842 		rxre->cmdstat = cpu_to_be32(SDMA_DESC_CMDSTAT_O
843 				| SDMA_DESC_CMDSTAT_EI | SDMA_DESC_CMDSTAT_F
844 				| SDMA_DESC_CMDSTAT_L);
845 		rxre->link = cpu_to_be32(dp_p + MPSC_RXRE_SIZE);
846 		rxre->buf_ptr = cpu_to_be32(bp_p);
847 
848 		dp += MPSC_RXRE_SIZE;
849 		dp_p += MPSC_RXRE_SIZE;
850 		bp += MPSC_RXBE_SIZE;
851 		bp_p += MPSC_RXBE_SIZE;
852 	}
853 	rxre->link = cpu_to_be32(pi->rxr_p);	/* Wrap last back to first */
854 
855 	/* Init tx ring descriptors */
856 	dp = pi->txr;
857 	dp_p = pi->txr_p;
858 	bp = pi->txb;
859 	bp_p = pi->txb_p;
860 
861 	for (i = 0; i < MPSC_TXR_ENTRIES; i++) {
862 		txre = (struct mpsc_tx_desc *)dp;
863 
864 		txre->link = cpu_to_be32(dp_p + MPSC_TXRE_SIZE);
865 		txre->buf_ptr = cpu_to_be32(bp_p);
866 
867 		dp += MPSC_TXRE_SIZE;
868 		dp_p += MPSC_TXRE_SIZE;
869 		bp += MPSC_TXBE_SIZE;
870 		bp_p += MPSC_TXBE_SIZE;
871 	}
872 	txre->link = cpu_to_be32(pi->txr_p);	/* Wrap last back to first */
873 
874 	dma_cache_sync(pi->port.dev, (void *)pi->dma_region,
875 			MPSC_DMA_ALLOC_SIZE, DMA_BIDIRECTIONAL);
876 #if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
877 		if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
878 			flush_dcache_range((ulong)pi->dma_region,
879 					(ulong)pi->dma_region
880 					+ MPSC_DMA_ALLOC_SIZE);
881 #endif
882 
883 	return;
884 }
885 
mpsc_uninit_rings(struct mpsc_port_info * pi)886 static void mpsc_uninit_rings(struct mpsc_port_info *pi)
887 {
888 	pr_debug("mpsc_uninit_rings[%d]: Uninitializing rings\n",pi->port.line);
889 
890 	BUG_ON(pi->dma_region == NULL);
891 
892 	pi->rxr = 0;
893 	pi->rxr_p = 0;
894 	pi->rxb = NULL;
895 	pi->rxb_p = NULL;
896 	pi->rxr_posn = 0;
897 
898 	pi->txr = 0;
899 	pi->txr_p = 0;
900 	pi->txb = NULL;
901 	pi->txb_p = NULL;
902 	pi->txr_head = 0;
903 	pi->txr_tail = 0;
904 }
905 
mpsc_make_ready(struct mpsc_port_info * pi)906 static int mpsc_make_ready(struct mpsc_port_info *pi)
907 {
908 	int rc;
909 
910 	pr_debug("mpsc_make_ready[%d]: Making cltr ready\n", pi->port.line);
911 
912 	if (!pi->ready) {
913 		mpsc_init_hw(pi);
914 		rc = mpsc_alloc_ring_mem(pi);
915 		if (rc)
916 			return rc;
917 		mpsc_init_rings(pi);
918 		pi->ready = 1;
919 	}
920 
921 	return 0;
922 }
923 
924 #ifdef CONFIG_CONSOLE_POLL
925 static int serial_polled;
926 #endif
927 
928 /*
929  ******************************************************************************
930  *
931  * Interrupt Handling Routines
932  *
933  ******************************************************************************
934  */
935 
mpsc_rx_intr(struct mpsc_port_info * pi,unsigned long * flags)936 static int mpsc_rx_intr(struct mpsc_port_info *pi, unsigned long *flags)
937 {
938 	struct mpsc_rx_desc *rxre;
939 	struct tty_port *port = &pi->port.state->port;
940 	u32	cmdstat, bytes_in, i;
941 	int	rc = 0;
942 	u8	*bp;
943 	char	flag = TTY_NORMAL;
944 
945 	pr_debug("mpsc_rx_intr[%d]: Handling Rx intr\n", pi->port.line);
946 
947 	rxre = (struct mpsc_rx_desc *)(pi->rxr + (pi->rxr_posn*MPSC_RXRE_SIZE));
948 
949 	dma_cache_sync(pi->port.dev, (void *)rxre, MPSC_RXRE_SIZE,
950 			DMA_FROM_DEVICE);
951 #if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
952 	if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
953 		invalidate_dcache_range((ulong)rxre,
954 				(ulong)rxre + MPSC_RXRE_SIZE);
955 #endif
956 
957 	/*
958 	 * Loop through Rx descriptors handling ones that have been completed.
959 	 */
960 	while (!((cmdstat = be32_to_cpu(rxre->cmdstat))
961 				& SDMA_DESC_CMDSTAT_O)) {
962 		bytes_in = be16_to_cpu(rxre->bytecnt);
963 #ifdef CONFIG_CONSOLE_POLL
964 		if (unlikely(serial_polled)) {
965 			serial_polled = 0;
966 			return 0;
967 		}
968 #endif
969 		/* Following use of tty struct directly is deprecated */
970 		if (tty_buffer_request_room(port, bytes_in) < bytes_in) {
971 			if (port->low_latency) {
972 				spin_unlock_irqrestore(&pi->port.lock, *flags);
973 				tty_flip_buffer_push(port);
974 				spin_lock_irqsave(&pi->port.lock, *flags);
975 			}
976 			/*
977 			 * If this failed then we will throw away the bytes
978 			 * but must do so to clear interrupts.
979 			 */
980 		}
981 
982 		bp = pi->rxb + (pi->rxr_posn * MPSC_RXBE_SIZE);
983 		dma_cache_sync(pi->port.dev, (void *)bp, MPSC_RXBE_SIZE,
984 				DMA_FROM_DEVICE);
985 #if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
986 		if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
987 			invalidate_dcache_range((ulong)bp,
988 					(ulong)bp + MPSC_RXBE_SIZE);
989 #endif
990 
991 		/*
992 		 * Other than for parity error, the manual provides little
993 		 * info on what data will be in a frame flagged by any of
994 		 * these errors.  For parity error, it is the last byte in
995 		 * the buffer that had the error.  As for the rest, I guess
996 		 * we'll assume there is no data in the buffer.
997 		 * If there is...it gets lost.
998 		 */
999 		if (unlikely(cmdstat & (SDMA_DESC_CMDSTAT_BR
1000 						| SDMA_DESC_CMDSTAT_FR
1001 						| SDMA_DESC_CMDSTAT_OR))) {
1002 
1003 			pi->port.icount.rx++;
1004 
1005 			if (cmdstat & SDMA_DESC_CMDSTAT_BR) {	/* Break */
1006 				pi->port.icount.brk++;
1007 
1008 				if (uart_handle_break(&pi->port))
1009 					goto next_frame;
1010 			} else if (cmdstat & SDMA_DESC_CMDSTAT_FR) {
1011 				pi->port.icount.frame++;
1012 			} else if (cmdstat & SDMA_DESC_CMDSTAT_OR) {
1013 				pi->port.icount.overrun++;
1014 			}
1015 
1016 			cmdstat &= pi->port.read_status_mask;
1017 
1018 			if (cmdstat & SDMA_DESC_CMDSTAT_BR)
1019 				flag = TTY_BREAK;
1020 			else if (cmdstat & SDMA_DESC_CMDSTAT_FR)
1021 				flag = TTY_FRAME;
1022 			else if (cmdstat & SDMA_DESC_CMDSTAT_OR)
1023 				flag = TTY_OVERRUN;
1024 			else if (cmdstat & SDMA_DESC_CMDSTAT_PE)
1025 				flag = TTY_PARITY;
1026 		}
1027 
1028 		if (uart_handle_sysrq_char(&pi->port, *bp)) {
1029 			bp++;
1030 			bytes_in--;
1031 #ifdef CONFIG_CONSOLE_POLL
1032 			if (unlikely(serial_polled)) {
1033 				serial_polled = 0;
1034 				return 0;
1035 			}
1036 #endif
1037 			goto next_frame;
1038 		}
1039 
1040 		if ((unlikely(cmdstat & (SDMA_DESC_CMDSTAT_BR
1041 						| SDMA_DESC_CMDSTAT_FR
1042 						| SDMA_DESC_CMDSTAT_OR)))
1043 				&& !(cmdstat & pi->port.ignore_status_mask)) {
1044 			tty_insert_flip_char(port, *bp, flag);
1045 		} else {
1046 			for (i=0; i<bytes_in; i++)
1047 				tty_insert_flip_char(port, *bp++, TTY_NORMAL);
1048 
1049 			pi->port.icount.rx += bytes_in;
1050 		}
1051 
1052 next_frame:
1053 		rxre->bytecnt = cpu_to_be16(0);
1054 		wmb();
1055 		rxre->cmdstat = cpu_to_be32(SDMA_DESC_CMDSTAT_O
1056 				| SDMA_DESC_CMDSTAT_EI | SDMA_DESC_CMDSTAT_F
1057 				| SDMA_DESC_CMDSTAT_L);
1058 		wmb();
1059 		dma_cache_sync(pi->port.dev, (void *)rxre, MPSC_RXRE_SIZE,
1060 				DMA_BIDIRECTIONAL);
1061 #if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
1062 		if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
1063 			flush_dcache_range((ulong)rxre,
1064 					(ulong)rxre + MPSC_RXRE_SIZE);
1065 #endif
1066 
1067 		/* Advance to next descriptor */
1068 		pi->rxr_posn = (pi->rxr_posn + 1) & (MPSC_RXR_ENTRIES - 1);
1069 		rxre = (struct mpsc_rx_desc *)
1070 			(pi->rxr + (pi->rxr_posn * MPSC_RXRE_SIZE));
1071 		dma_cache_sync(pi->port.dev, (void *)rxre, MPSC_RXRE_SIZE,
1072 				DMA_FROM_DEVICE);
1073 #if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
1074 		if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
1075 			invalidate_dcache_range((ulong)rxre,
1076 					(ulong)rxre + MPSC_RXRE_SIZE);
1077 #endif
1078 		rc = 1;
1079 	}
1080 
1081 	/* Restart rx engine, if its stopped */
1082 	if ((readl(pi->sdma_base + SDMA_SDCM) & SDMA_SDCM_ERD) == 0)
1083 		mpsc_start_rx(pi);
1084 
1085 	spin_unlock_irqrestore(&pi->port.lock, *flags);
1086 	tty_flip_buffer_push(port);
1087 	spin_lock_irqsave(&pi->port.lock, *flags);
1088 	return rc;
1089 }
1090 
mpsc_setup_tx_desc(struct mpsc_port_info * pi,u32 count,u32 intr)1091 static void mpsc_setup_tx_desc(struct mpsc_port_info *pi, u32 count, u32 intr)
1092 {
1093 	struct mpsc_tx_desc *txre;
1094 
1095 	txre = (struct mpsc_tx_desc *)(pi->txr
1096 			+ (pi->txr_head * MPSC_TXRE_SIZE));
1097 
1098 	txre->bytecnt = cpu_to_be16(count);
1099 	txre->shadow = txre->bytecnt;
1100 	wmb();			/* ensure cmdstat is last field updated */
1101 	txre->cmdstat = cpu_to_be32(SDMA_DESC_CMDSTAT_O | SDMA_DESC_CMDSTAT_F
1102 			| SDMA_DESC_CMDSTAT_L
1103 			| ((intr) ? SDMA_DESC_CMDSTAT_EI : 0));
1104 	wmb();
1105 	dma_cache_sync(pi->port.dev, (void *)txre, MPSC_TXRE_SIZE,
1106 			DMA_BIDIRECTIONAL);
1107 #if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
1108 	if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
1109 		flush_dcache_range((ulong)txre,
1110 				(ulong)txre + MPSC_TXRE_SIZE);
1111 #endif
1112 }
1113 
mpsc_copy_tx_data(struct mpsc_port_info * pi)1114 static void mpsc_copy_tx_data(struct mpsc_port_info *pi)
1115 {
1116 	struct circ_buf *xmit = &pi->port.state->xmit;
1117 	u8 *bp;
1118 	u32 i;
1119 
1120 	/* Make sure the desc ring isn't full */
1121 	while (CIRC_CNT(pi->txr_head, pi->txr_tail, MPSC_TXR_ENTRIES)
1122 			< (MPSC_TXR_ENTRIES - 1)) {
1123 		if (pi->port.x_char) {
1124 			/*
1125 			 * Ideally, we should use the TCS field in
1126 			 * CHR_1 to put the x_char out immediately but
1127 			 * errata prevents us from being able to read
1128 			 * CHR_2 to know that its safe to write to
1129 			 * CHR_1.  Instead, just put it in-band with
1130 			 * all the other Tx data.
1131 			 */
1132 			bp = pi->txb + (pi->txr_head * MPSC_TXBE_SIZE);
1133 			*bp = pi->port.x_char;
1134 			pi->port.x_char = 0;
1135 			i = 1;
1136 		} else if (!uart_circ_empty(xmit)
1137 				&& !uart_tx_stopped(&pi->port)) {
1138 			i = min((u32)MPSC_TXBE_SIZE,
1139 				(u32)uart_circ_chars_pending(xmit));
1140 			i = min(i, (u32)CIRC_CNT_TO_END(xmit->head, xmit->tail,
1141 				UART_XMIT_SIZE));
1142 			bp = pi->txb + (pi->txr_head * MPSC_TXBE_SIZE);
1143 			memcpy(bp, &xmit->buf[xmit->tail], i);
1144 			xmit->tail = (xmit->tail + i) & (UART_XMIT_SIZE - 1);
1145 
1146 			if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
1147 				uart_write_wakeup(&pi->port);
1148 		} else { /* All tx data copied into ring bufs */
1149 			return;
1150 		}
1151 
1152 		dma_cache_sync(pi->port.dev, (void *)bp, MPSC_TXBE_SIZE,
1153 				DMA_BIDIRECTIONAL);
1154 #if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
1155 		if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
1156 			flush_dcache_range((ulong)bp,
1157 					(ulong)bp + MPSC_TXBE_SIZE);
1158 #endif
1159 		mpsc_setup_tx_desc(pi, i, 1);
1160 
1161 		/* Advance to next descriptor */
1162 		pi->txr_head = (pi->txr_head + 1) & (MPSC_TXR_ENTRIES - 1);
1163 	}
1164 }
1165 
mpsc_tx_intr(struct mpsc_port_info * pi)1166 static int mpsc_tx_intr(struct mpsc_port_info *pi)
1167 {
1168 	struct mpsc_tx_desc *txre;
1169 	int rc = 0;
1170 	unsigned long iflags;
1171 
1172 	spin_lock_irqsave(&pi->tx_lock, iflags);
1173 
1174 	if (!mpsc_sdma_tx_active(pi)) {
1175 		txre = (struct mpsc_tx_desc *)(pi->txr
1176 				+ (pi->txr_tail * MPSC_TXRE_SIZE));
1177 
1178 		dma_cache_sync(pi->port.dev, (void *)txre, MPSC_TXRE_SIZE,
1179 				DMA_FROM_DEVICE);
1180 #if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
1181 		if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
1182 			invalidate_dcache_range((ulong)txre,
1183 					(ulong)txre + MPSC_TXRE_SIZE);
1184 #endif
1185 
1186 		while (!(be32_to_cpu(txre->cmdstat) & SDMA_DESC_CMDSTAT_O)) {
1187 			rc = 1;
1188 			pi->port.icount.tx += be16_to_cpu(txre->bytecnt);
1189 			pi->txr_tail = (pi->txr_tail+1) & (MPSC_TXR_ENTRIES-1);
1190 
1191 			/* If no more data to tx, fall out of loop */
1192 			if (pi->txr_head == pi->txr_tail)
1193 				break;
1194 
1195 			txre = (struct mpsc_tx_desc *)(pi->txr
1196 					+ (pi->txr_tail * MPSC_TXRE_SIZE));
1197 			dma_cache_sync(pi->port.dev, (void *)txre,
1198 					MPSC_TXRE_SIZE, DMA_FROM_DEVICE);
1199 #if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
1200 			if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
1201 				invalidate_dcache_range((ulong)txre,
1202 						(ulong)txre + MPSC_TXRE_SIZE);
1203 #endif
1204 		}
1205 
1206 		mpsc_copy_tx_data(pi);
1207 		mpsc_sdma_start_tx(pi);	/* start next desc if ready */
1208 	}
1209 
1210 	spin_unlock_irqrestore(&pi->tx_lock, iflags);
1211 	return rc;
1212 }
1213 
1214 /*
1215  * This is the driver's interrupt handler.  To avoid a race, we first clear
1216  * the interrupt, then handle any completed Rx/Tx descriptors.  When done
1217  * handling those descriptors, we restart the Rx/Tx engines if they're stopped.
1218  */
mpsc_sdma_intr(int irq,void * dev_id)1219 static irqreturn_t mpsc_sdma_intr(int irq, void *dev_id)
1220 {
1221 	struct mpsc_port_info *pi = dev_id;
1222 	ulong iflags;
1223 	int rc = IRQ_NONE;
1224 
1225 	pr_debug("mpsc_sdma_intr[%d]: SDMA Interrupt Received\n",pi->port.line);
1226 
1227 	spin_lock_irqsave(&pi->port.lock, iflags);
1228 	mpsc_sdma_intr_ack(pi);
1229 	if (mpsc_rx_intr(pi, &iflags))
1230 		rc = IRQ_HANDLED;
1231 	if (mpsc_tx_intr(pi))
1232 		rc = IRQ_HANDLED;
1233 	spin_unlock_irqrestore(&pi->port.lock, iflags);
1234 
1235 	pr_debug("mpsc_sdma_intr[%d]: SDMA Interrupt Handled\n", pi->port.line);
1236 	return rc;
1237 }
1238 
1239 /*
1240  ******************************************************************************
1241  *
1242  * serial_core.c Interface routines
1243  *
1244  ******************************************************************************
1245  */
mpsc_tx_empty(struct uart_port * port)1246 static uint mpsc_tx_empty(struct uart_port *port)
1247 {
1248 	struct mpsc_port_info *pi =
1249 		container_of(port, struct mpsc_port_info, port);
1250 	ulong iflags;
1251 	uint rc;
1252 
1253 	spin_lock_irqsave(&pi->port.lock, iflags);
1254 	rc = mpsc_sdma_tx_active(pi) ? 0 : TIOCSER_TEMT;
1255 	spin_unlock_irqrestore(&pi->port.lock, iflags);
1256 
1257 	return rc;
1258 }
1259 
mpsc_set_mctrl(struct uart_port * port,uint mctrl)1260 static void mpsc_set_mctrl(struct uart_port *port, uint mctrl)
1261 {
1262 	/* Have no way to set modem control lines AFAICT */
1263 }
1264 
mpsc_get_mctrl(struct uart_port * port)1265 static uint mpsc_get_mctrl(struct uart_port *port)
1266 {
1267 	struct mpsc_port_info *pi =
1268 		container_of(port, struct mpsc_port_info, port);
1269 	u32 mflags, status;
1270 
1271 	status = (pi->mirror_regs) ? pi->MPSC_CHR_10_m
1272 		: readl(pi->mpsc_base + MPSC_CHR_10);
1273 
1274 	mflags = 0;
1275 	if (status & 0x1)
1276 		mflags |= TIOCM_CTS;
1277 	if (status & 0x2)
1278 		mflags |= TIOCM_CAR;
1279 
1280 	return mflags | TIOCM_DSR;	/* No way to tell if DSR asserted */
1281 }
1282 
mpsc_stop_tx(struct uart_port * port)1283 static void mpsc_stop_tx(struct uart_port *port)
1284 {
1285 	struct mpsc_port_info *pi =
1286 		container_of(port, struct mpsc_port_info, port);
1287 
1288 	pr_debug("mpsc_stop_tx[%d]\n", port->line);
1289 
1290 	mpsc_freeze(pi);
1291 }
1292 
mpsc_start_tx(struct uart_port * port)1293 static void mpsc_start_tx(struct uart_port *port)
1294 {
1295 	struct mpsc_port_info *pi =
1296 		container_of(port, struct mpsc_port_info, port);
1297 	unsigned long iflags;
1298 
1299 	spin_lock_irqsave(&pi->tx_lock, iflags);
1300 
1301 	mpsc_unfreeze(pi);
1302 	mpsc_copy_tx_data(pi);
1303 	mpsc_sdma_start_tx(pi);
1304 
1305 	spin_unlock_irqrestore(&pi->tx_lock, iflags);
1306 
1307 	pr_debug("mpsc_start_tx[%d]\n", port->line);
1308 }
1309 
mpsc_start_rx(struct mpsc_port_info * pi)1310 static void mpsc_start_rx(struct mpsc_port_info *pi)
1311 {
1312 	pr_debug("mpsc_start_rx[%d]: Starting...\n", pi->port.line);
1313 
1314 	if (pi->rcv_data) {
1315 		mpsc_enter_hunt(pi);
1316 		mpsc_sdma_cmd(pi, SDMA_SDCM_ERD);
1317 	}
1318 }
1319 
mpsc_stop_rx(struct uart_port * port)1320 static void mpsc_stop_rx(struct uart_port *port)
1321 {
1322 	struct mpsc_port_info *pi =
1323 		container_of(port, struct mpsc_port_info, port);
1324 
1325 	pr_debug("mpsc_stop_rx[%d]: Stopping...\n", port->line);
1326 
1327 	if (pi->mirror_regs) {
1328 		writel(pi->MPSC_CHR_2_m | MPSC_CHR_2_RA,
1329 				pi->mpsc_base + MPSC_CHR_2);
1330 		/* Erratum prevents reading CHR_2 so just delay for a while */
1331 		udelay(100);
1332 	} else {
1333 		writel(readl(pi->mpsc_base + MPSC_CHR_2) | MPSC_CHR_2_RA,
1334 				pi->mpsc_base + MPSC_CHR_2);
1335 
1336 		while (readl(pi->mpsc_base + MPSC_CHR_2) & MPSC_CHR_2_RA)
1337 			udelay(10);
1338 	}
1339 
1340 	mpsc_sdma_cmd(pi, SDMA_SDCM_AR);
1341 }
1342 
mpsc_break_ctl(struct uart_port * port,int ctl)1343 static void mpsc_break_ctl(struct uart_port *port, int ctl)
1344 {
1345 	struct mpsc_port_info *pi =
1346 		container_of(port, struct mpsc_port_info, port);
1347 	ulong	flags;
1348 	u32	v;
1349 
1350 	v = ctl ? 0x00ff0000 : 0;
1351 
1352 	spin_lock_irqsave(&pi->port.lock, flags);
1353 	if (pi->mirror_regs)
1354 		pi->MPSC_CHR_1_m = v;
1355 	writel(v, pi->mpsc_base + MPSC_CHR_1);
1356 	spin_unlock_irqrestore(&pi->port.lock, flags);
1357 }
1358 
mpsc_startup(struct uart_port * port)1359 static int mpsc_startup(struct uart_port *port)
1360 {
1361 	struct mpsc_port_info *pi =
1362 		container_of(port, struct mpsc_port_info, port);
1363 	u32 flag = 0;
1364 	int rc;
1365 
1366 	pr_debug("mpsc_startup[%d]: Starting up MPSC, irq: %d\n",
1367 		port->line, pi->port.irq);
1368 
1369 	if ((rc = mpsc_make_ready(pi)) == 0) {
1370 		/* Setup IRQ handler */
1371 		mpsc_sdma_intr_ack(pi);
1372 
1373 		/* If irq's are shared, need to set flag */
1374 		if (mpsc_ports[0].port.irq == mpsc_ports[1].port.irq)
1375 			flag = IRQF_SHARED;
1376 
1377 		if (request_irq(pi->port.irq, mpsc_sdma_intr, flag,
1378 					"mpsc-sdma", pi))
1379 			printk(KERN_ERR "MPSC: Can't get SDMA IRQ %d\n",
1380 					pi->port.irq);
1381 
1382 		mpsc_sdma_intr_unmask(pi, 0xf);
1383 		mpsc_sdma_set_rx_ring(pi, (struct mpsc_rx_desc *)(pi->rxr_p
1384 					+ (pi->rxr_posn * MPSC_RXRE_SIZE)));
1385 	}
1386 
1387 	return rc;
1388 }
1389 
mpsc_shutdown(struct uart_port * port)1390 static void mpsc_shutdown(struct uart_port *port)
1391 {
1392 	struct mpsc_port_info *pi =
1393 		container_of(port, struct mpsc_port_info, port);
1394 
1395 	pr_debug("mpsc_shutdown[%d]: Shutting down MPSC\n", port->line);
1396 
1397 	mpsc_sdma_stop(pi);
1398 	free_irq(pi->port.irq, pi);
1399 }
1400 
mpsc_set_termios(struct uart_port * port,struct ktermios * termios,struct ktermios * old)1401 static void mpsc_set_termios(struct uart_port *port, struct ktermios *termios,
1402 		 struct ktermios *old)
1403 {
1404 	struct mpsc_port_info *pi =
1405 		container_of(port, struct mpsc_port_info, port);
1406 	u32 baud;
1407 	ulong flags;
1408 	u32 chr_bits, stop_bits, par;
1409 
1410 	switch (termios->c_cflag & CSIZE) {
1411 	case CS5:
1412 		chr_bits = MPSC_MPCR_CL_5;
1413 		break;
1414 	case CS6:
1415 		chr_bits = MPSC_MPCR_CL_6;
1416 		break;
1417 	case CS7:
1418 		chr_bits = MPSC_MPCR_CL_7;
1419 		break;
1420 	case CS8:
1421 	default:
1422 		chr_bits = MPSC_MPCR_CL_8;
1423 		break;
1424 	}
1425 
1426 	if (termios->c_cflag & CSTOPB)
1427 		stop_bits = MPSC_MPCR_SBL_2;
1428 	else
1429 		stop_bits = MPSC_MPCR_SBL_1;
1430 
1431 	par = MPSC_CHR_2_PAR_EVEN;
1432 	if (termios->c_cflag & PARENB)
1433 		if (termios->c_cflag & PARODD)
1434 			par = MPSC_CHR_2_PAR_ODD;
1435 #ifdef	CMSPAR
1436 		if (termios->c_cflag & CMSPAR) {
1437 			if (termios->c_cflag & PARODD)
1438 				par = MPSC_CHR_2_PAR_MARK;
1439 			else
1440 				par = MPSC_CHR_2_PAR_SPACE;
1441 		}
1442 #endif
1443 
1444 	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk);
1445 
1446 	spin_lock_irqsave(&pi->port.lock, flags);
1447 
1448 	uart_update_timeout(port, termios->c_cflag, baud);
1449 
1450 	mpsc_set_char_length(pi, chr_bits);
1451 	mpsc_set_stop_bit_length(pi, stop_bits);
1452 	mpsc_set_parity(pi, par);
1453 	mpsc_set_baudrate(pi, baud);
1454 
1455 	/* Characters/events to read */
1456 	pi->port.read_status_mask = SDMA_DESC_CMDSTAT_OR;
1457 
1458 	if (termios->c_iflag & INPCK)
1459 		pi->port.read_status_mask |= SDMA_DESC_CMDSTAT_PE
1460 			| SDMA_DESC_CMDSTAT_FR;
1461 
1462 	if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
1463 		pi->port.read_status_mask |= SDMA_DESC_CMDSTAT_BR;
1464 
1465 	/* Characters/events to ignore */
1466 	pi->port.ignore_status_mask = 0;
1467 
1468 	if (termios->c_iflag & IGNPAR)
1469 		pi->port.ignore_status_mask |= SDMA_DESC_CMDSTAT_PE
1470 			| SDMA_DESC_CMDSTAT_FR;
1471 
1472 	if (termios->c_iflag & IGNBRK) {
1473 		pi->port.ignore_status_mask |= SDMA_DESC_CMDSTAT_BR;
1474 
1475 		if (termios->c_iflag & IGNPAR)
1476 			pi->port.ignore_status_mask |= SDMA_DESC_CMDSTAT_OR;
1477 	}
1478 
1479 	if ((termios->c_cflag & CREAD)) {
1480 		if (!pi->rcv_data) {
1481 			pi->rcv_data = 1;
1482 			mpsc_start_rx(pi);
1483 		}
1484 	} else if (pi->rcv_data) {
1485 		mpsc_stop_rx(port);
1486 		pi->rcv_data = 0;
1487 	}
1488 
1489 	spin_unlock_irqrestore(&pi->port.lock, flags);
1490 }
1491 
mpsc_type(struct uart_port * port)1492 static const char *mpsc_type(struct uart_port *port)
1493 {
1494 	pr_debug("mpsc_type[%d]: port type: %s\n", port->line,MPSC_DRIVER_NAME);
1495 	return MPSC_DRIVER_NAME;
1496 }
1497 
mpsc_request_port(struct uart_port * port)1498 static int mpsc_request_port(struct uart_port *port)
1499 {
1500 	/* Should make chip/platform specific call */
1501 	return 0;
1502 }
1503 
mpsc_release_port(struct uart_port * port)1504 static void mpsc_release_port(struct uart_port *port)
1505 {
1506 	struct mpsc_port_info *pi =
1507 		container_of(port, struct mpsc_port_info, port);
1508 
1509 	if (pi->ready) {
1510 		mpsc_uninit_rings(pi);
1511 		mpsc_free_ring_mem(pi);
1512 		pi->ready = 0;
1513 	}
1514 }
1515 
mpsc_config_port(struct uart_port * port,int flags)1516 static void mpsc_config_port(struct uart_port *port, int flags)
1517 {
1518 }
1519 
mpsc_verify_port(struct uart_port * port,struct serial_struct * ser)1520 static int mpsc_verify_port(struct uart_port *port, struct serial_struct *ser)
1521 {
1522 	struct mpsc_port_info *pi =
1523 		container_of(port, struct mpsc_port_info, port);
1524 	int rc = 0;
1525 
1526 	pr_debug("mpsc_verify_port[%d]: Verifying port data\n", pi->port.line);
1527 
1528 	if (ser->type != PORT_UNKNOWN && ser->type != PORT_MPSC)
1529 		rc = -EINVAL;
1530 	else if (pi->port.irq != ser->irq)
1531 		rc = -EINVAL;
1532 	else if (ser->io_type != SERIAL_IO_MEM)
1533 		rc = -EINVAL;
1534 	else if (pi->port.uartclk / 16 != ser->baud_base) /* Not sure */
1535 		rc = -EINVAL;
1536 	else if ((void *)pi->port.mapbase != ser->iomem_base)
1537 		rc = -EINVAL;
1538 	else if (pi->port.iobase != ser->port)
1539 		rc = -EINVAL;
1540 	else if (ser->hub6 != 0)
1541 		rc = -EINVAL;
1542 
1543 	return rc;
1544 }
1545 #ifdef CONFIG_CONSOLE_POLL
1546 /* Serial polling routines for writing and reading from the uart while
1547  * in an interrupt or debug context.
1548  */
1549 
1550 static char poll_buf[2048];
1551 static int poll_ptr;
1552 static int poll_cnt;
1553 static void mpsc_put_poll_char(struct uart_port *port,
1554 							   unsigned char c);
1555 
mpsc_get_poll_char(struct uart_port * port)1556 static int mpsc_get_poll_char(struct uart_port *port)
1557 {
1558 	struct mpsc_port_info *pi =
1559 		container_of(port, struct mpsc_port_info, port);
1560 	struct mpsc_rx_desc *rxre;
1561 	u32	cmdstat, bytes_in, i;
1562 	u8	*bp;
1563 
1564 	if (!serial_polled)
1565 		serial_polled = 1;
1566 
1567 	pr_debug("mpsc_rx_intr[%d]: Handling Rx intr\n", pi->port.line);
1568 
1569 	if (poll_cnt) {
1570 		poll_cnt--;
1571 		return poll_buf[poll_ptr++];
1572 	}
1573 	poll_ptr = 0;
1574 	poll_cnt = 0;
1575 
1576 	while (poll_cnt == 0) {
1577 		rxre = (struct mpsc_rx_desc *)(pi->rxr +
1578 		       (pi->rxr_posn*MPSC_RXRE_SIZE));
1579 		dma_cache_sync(pi->port.dev, (void *)rxre,
1580 			       MPSC_RXRE_SIZE, DMA_FROM_DEVICE);
1581 #if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
1582 		if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
1583 			invalidate_dcache_range((ulong)rxre,
1584 			(ulong)rxre + MPSC_RXRE_SIZE);
1585 #endif
1586 		/*
1587 		 * Loop through Rx descriptors handling ones that have
1588 		 * been completed.
1589 		 */
1590 		while (poll_cnt == 0 &&
1591 		       !((cmdstat = be32_to_cpu(rxre->cmdstat)) &
1592 			 SDMA_DESC_CMDSTAT_O)){
1593 			bytes_in = be16_to_cpu(rxre->bytecnt);
1594 			bp = pi->rxb + (pi->rxr_posn * MPSC_RXBE_SIZE);
1595 			dma_cache_sync(pi->port.dev, (void *) bp,
1596 				       MPSC_RXBE_SIZE, DMA_FROM_DEVICE);
1597 #if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
1598 			if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
1599 				invalidate_dcache_range((ulong)bp,
1600 					(ulong)bp + MPSC_RXBE_SIZE);
1601 #endif
1602 			if ((unlikely(cmdstat & (SDMA_DESC_CMDSTAT_BR |
1603 			 SDMA_DESC_CMDSTAT_FR | SDMA_DESC_CMDSTAT_OR))) &&
1604 				!(cmdstat & pi->port.ignore_status_mask)) {
1605 				poll_buf[poll_cnt] = *bp;
1606 				poll_cnt++;
1607 			} else {
1608 				for (i = 0; i < bytes_in; i++) {
1609 					poll_buf[poll_cnt] = *bp++;
1610 					poll_cnt++;
1611 				}
1612 				pi->port.icount.rx += bytes_in;
1613 			}
1614 			rxre->bytecnt = cpu_to_be16(0);
1615 			wmb();
1616 			rxre->cmdstat = cpu_to_be32(SDMA_DESC_CMDSTAT_O |
1617 						    SDMA_DESC_CMDSTAT_EI |
1618 						    SDMA_DESC_CMDSTAT_F |
1619 						    SDMA_DESC_CMDSTAT_L);
1620 			wmb();
1621 			dma_cache_sync(pi->port.dev, (void *)rxre,
1622 				       MPSC_RXRE_SIZE, DMA_BIDIRECTIONAL);
1623 #if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
1624 			if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
1625 				flush_dcache_range((ulong)rxre,
1626 					   (ulong)rxre + MPSC_RXRE_SIZE);
1627 #endif
1628 
1629 			/* Advance to next descriptor */
1630 			pi->rxr_posn = (pi->rxr_posn + 1) &
1631 				(MPSC_RXR_ENTRIES - 1);
1632 			rxre = (struct mpsc_rx_desc *)(pi->rxr +
1633 				       (pi->rxr_posn * MPSC_RXRE_SIZE));
1634 			dma_cache_sync(pi->port.dev, (void *)rxre,
1635 				       MPSC_RXRE_SIZE, DMA_FROM_DEVICE);
1636 #if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
1637 			if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
1638 				invalidate_dcache_range((ulong)rxre,
1639 						(ulong)rxre + MPSC_RXRE_SIZE);
1640 #endif
1641 		}
1642 
1643 		/* Restart rx engine, if its stopped */
1644 		if ((readl(pi->sdma_base + SDMA_SDCM) & SDMA_SDCM_ERD) == 0)
1645 			mpsc_start_rx(pi);
1646 	}
1647 	if (poll_cnt) {
1648 		poll_cnt--;
1649 		return poll_buf[poll_ptr++];
1650 	}
1651 
1652 	return 0;
1653 }
1654 
1655 
mpsc_put_poll_char(struct uart_port * port,unsigned char c)1656 static void mpsc_put_poll_char(struct uart_port *port,
1657 			 unsigned char c)
1658 {
1659 	struct mpsc_port_info *pi =
1660 		container_of(port, struct mpsc_port_info, port);
1661 	u32 data;
1662 
1663 	data = readl(pi->mpsc_base + MPSC_MPCR);
1664 	writeb(c, pi->mpsc_base + MPSC_CHR_1);
1665 	mb();
1666 	data = readl(pi->mpsc_base + MPSC_CHR_2);
1667 	data |= MPSC_CHR_2_TTCS;
1668 	writel(data, pi->mpsc_base + MPSC_CHR_2);
1669 	mb();
1670 
1671 	while (readl(pi->mpsc_base + MPSC_CHR_2) & MPSC_CHR_2_TTCS);
1672 }
1673 #endif
1674 
1675 static const struct uart_ops mpsc_pops = {
1676 	.tx_empty	= mpsc_tx_empty,
1677 	.set_mctrl	= mpsc_set_mctrl,
1678 	.get_mctrl	= mpsc_get_mctrl,
1679 	.stop_tx	= mpsc_stop_tx,
1680 	.start_tx	= mpsc_start_tx,
1681 	.stop_rx	= mpsc_stop_rx,
1682 	.break_ctl	= mpsc_break_ctl,
1683 	.startup	= mpsc_startup,
1684 	.shutdown	= mpsc_shutdown,
1685 	.set_termios	= mpsc_set_termios,
1686 	.type		= mpsc_type,
1687 	.release_port	= mpsc_release_port,
1688 	.request_port	= mpsc_request_port,
1689 	.config_port	= mpsc_config_port,
1690 	.verify_port	= mpsc_verify_port,
1691 #ifdef CONFIG_CONSOLE_POLL
1692 	.poll_get_char = mpsc_get_poll_char,
1693 	.poll_put_char = mpsc_put_poll_char,
1694 #endif
1695 };
1696 
1697 /*
1698  ******************************************************************************
1699  *
1700  * Console Interface Routines
1701  *
1702  ******************************************************************************
1703  */
1704 
1705 #ifdef CONFIG_SERIAL_MPSC_CONSOLE
mpsc_console_write(struct console * co,const char * s,uint count)1706 static void mpsc_console_write(struct console *co, const char *s, uint count)
1707 {
1708 	struct mpsc_port_info *pi = &mpsc_ports[co->index];
1709 	u8 *bp, *dp, add_cr = 0;
1710 	int i;
1711 	unsigned long iflags;
1712 
1713 	spin_lock_irqsave(&pi->tx_lock, iflags);
1714 
1715 	while (pi->txr_head != pi->txr_tail) {
1716 		while (mpsc_sdma_tx_active(pi))
1717 			udelay(100);
1718 		mpsc_sdma_intr_ack(pi);
1719 		mpsc_tx_intr(pi);
1720 	}
1721 
1722 	while (mpsc_sdma_tx_active(pi))
1723 		udelay(100);
1724 
1725 	while (count > 0) {
1726 		bp = dp = pi->txb + (pi->txr_head * MPSC_TXBE_SIZE);
1727 
1728 		for (i = 0; i < MPSC_TXBE_SIZE; i++) {
1729 			if (count == 0)
1730 				break;
1731 
1732 			if (add_cr) {
1733 				*(dp++) = '\r';
1734 				add_cr = 0;
1735 			} else {
1736 				*(dp++) = *s;
1737 
1738 				if (*(s++) == '\n') { /* add '\r' after '\n' */
1739 					add_cr = 1;
1740 					count++;
1741 				}
1742 			}
1743 
1744 			count--;
1745 		}
1746 
1747 		dma_cache_sync(pi->port.dev, (void *)bp, MPSC_TXBE_SIZE,
1748 				DMA_BIDIRECTIONAL);
1749 #if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
1750 		if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
1751 			flush_dcache_range((ulong)bp,
1752 					(ulong)bp + MPSC_TXBE_SIZE);
1753 #endif
1754 		mpsc_setup_tx_desc(pi, i, 0);
1755 		pi->txr_head = (pi->txr_head + 1) & (MPSC_TXR_ENTRIES - 1);
1756 		mpsc_sdma_start_tx(pi);
1757 
1758 		while (mpsc_sdma_tx_active(pi))
1759 			udelay(100);
1760 
1761 		pi->txr_tail = (pi->txr_tail + 1) & (MPSC_TXR_ENTRIES - 1);
1762 	}
1763 
1764 	spin_unlock_irqrestore(&pi->tx_lock, iflags);
1765 }
1766 
mpsc_console_setup(struct console * co,char * options)1767 static int __init mpsc_console_setup(struct console *co, char *options)
1768 {
1769 	struct mpsc_port_info *pi;
1770 	int baud, bits, parity, flow;
1771 
1772 	pr_debug("mpsc_console_setup[%d]: options: %s\n", co->index, options);
1773 
1774 	if (co->index >= MPSC_NUM_CTLRS)
1775 		co->index = 0;
1776 
1777 	pi = &mpsc_ports[co->index];
1778 
1779 	baud = pi->default_baud;
1780 	bits = pi->default_bits;
1781 	parity = pi->default_parity;
1782 	flow = pi->default_flow;
1783 
1784 	if (!pi->port.ops)
1785 		return -ENODEV;
1786 
1787 	spin_lock_init(&pi->port.lock);	/* Temporary fix--copied from 8250.c */
1788 
1789 	if (options)
1790 		uart_parse_options(options, &baud, &parity, &bits, &flow);
1791 
1792 	return uart_set_options(&pi->port, co, baud, parity, bits, flow);
1793 }
1794 
1795 static struct console mpsc_console = {
1796 	.name	= MPSC_DEV_NAME,
1797 	.write	= mpsc_console_write,
1798 	.device	= uart_console_device,
1799 	.setup	= mpsc_console_setup,
1800 	.flags	= CON_PRINTBUFFER,
1801 	.index	= -1,
1802 	.data	= &mpsc_reg,
1803 };
1804 
mpsc_late_console_init(void)1805 static int __init mpsc_late_console_init(void)
1806 {
1807 	pr_debug("mpsc_late_console_init: Enter\n");
1808 
1809 	if (!(mpsc_console.flags & CON_ENABLED))
1810 		register_console(&mpsc_console);
1811 	return 0;
1812 }
1813 
1814 late_initcall(mpsc_late_console_init);
1815 
1816 #define MPSC_CONSOLE	&mpsc_console
1817 #else
1818 #define MPSC_CONSOLE	NULL
1819 #endif
1820 /*
1821  ******************************************************************************
1822  *
1823  * Dummy Platform Driver to extract & map shared register regions
1824  *
1825  ******************************************************************************
1826  */
mpsc_resource_err(char * s)1827 static void mpsc_resource_err(char *s)
1828 {
1829 	printk(KERN_WARNING "MPSC: Platform device resource error in %s\n", s);
1830 }
1831 
mpsc_shared_map_regs(struct platform_device * pd)1832 static int mpsc_shared_map_regs(struct platform_device *pd)
1833 {
1834 	struct resource	*r;
1835 
1836 	if ((r = platform_get_resource(pd, IORESOURCE_MEM,
1837 					MPSC_ROUTING_BASE_ORDER))
1838 			&& request_mem_region(r->start,
1839 				MPSC_ROUTING_REG_BLOCK_SIZE,
1840 				"mpsc_routing_regs")) {
1841 		mpsc_shared_regs.mpsc_routing_base = ioremap(r->start,
1842 				MPSC_ROUTING_REG_BLOCK_SIZE);
1843 		mpsc_shared_regs.mpsc_routing_base_p = r->start;
1844 	} else {
1845 		mpsc_resource_err("MPSC routing base");
1846 		return -ENOMEM;
1847 	}
1848 
1849 	if ((r = platform_get_resource(pd, IORESOURCE_MEM,
1850 					MPSC_SDMA_INTR_BASE_ORDER))
1851 			&& request_mem_region(r->start,
1852 				MPSC_SDMA_INTR_REG_BLOCK_SIZE,
1853 				"sdma_intr_regs")) {
1854 		mpsc_shared_regs.sdma_intr_base = ioremap(r->start,
1855 			MPSC_SDMA_INTR_REG_BLOCK_SIZE);
1856 		mpsc_shared_regs.sdma_intr_base_p = r->start;
1857 	} else {
1858 		iounmap(mpsc_shared_regs.mpsc_routing_base);
1859 		release_mem_region(mpsc_shared_regs.mpsc_routing_base_p,
1860 				MPSC_ROUTING_REG_BLOCK_SIZE);
1861 		mpsc_resource_err("SDMA intr base");
1862 		return -ENOMEM;
1863 	}
1864 
1865 	return 0;
1866 }
1867 
mpsc_shared_unmap_regs(void)1868 static void mpsc_shared_unmap_regs(void)
1869 {
1870 	if (mpsc_shared_regs.mpsc_routing_base) {
1871 		iounmap(mpsc_shared_regs.mpsc_routing_base);
1872 		release_mem_region(mpsc_shared_regs.mpsc_routing_base_p,
1873 				MPSC_ROUTING_REG_BLOCK_SIZE);
1874 	}
1875 	if (mpsc_shared_regs.sdma_intr_base) {
1876 		iounmap(mpsc_shared_regs.sdma_intr_base);
1877 		release_mem_region(mpsc_shared_regs.sdma_intr_base_p,
1878 				MPSC_SDMA_INTR_REG_BLOCK_SIZE);
1879 	}
1880 
1881 	mpsc_shared_regs.mpsc_routing_base = NULL;
1882 	mpsc_shared_regs.sdma_intr_base = NULL;
1883 
1884 	mpsc_shared_regs.mpsc_routing_base_p = 0;
1885 	mpsc_shared_regs.sdma_intr_base_p = 0;
1886 }
1887 
mpsc_shared_drv_probe(struct platform_device * dev)1888 static int mpsc_shared_drv_probe(struct platform_device *dev)
1889 {
1890 	struct mpsc_shared_pdata	*pdata;
1891 	int rc;
1892 
1893 	if (dev->id != 0)
1894 		return -ENODEV;
1895 
1896 	rc = mpsc_shared_map_regs(dev);
1897 	if (rc)
1898 		return rc;
1899 
1900 	pdata = dev_get_platdata(&dev->dev);
1901 
1902 	mpsc_shared_regs.MPSC_MRR_m = pdata->mrr_val;
1903 	mpsc_shared_regs.MPSC_RCRR_m= pdata->rcrr_val;
1904 	mpsc_shared_regs.MPSC_TCRR_m= pdata->tcrr_val;
1905 	mpsc_shared_regs.SDMA_INTR_CAUSE_m = pdata->intr_cause_val;
1906 	mpsc_shared_regs.SDMA_INTR_MASK_m = pdata->intr_mask_val;
1907 
1908 	return 0;
1909 }
1910 
mpsc_shared_drv_remove(struct platform_device * dev)1911 static int mpsc_shared_drv_remove(struct platform_device *dev)
1912 {
1913 	if (dev->id != 0)
1914 		return -ENODEV;
1915 
1916 	mpsc_shared_unmap_regs();
1917 	mpsc_shared_regs.MPSC_MRR_m = 0;
1918 	mpsc_shared_regs.MPSC_RCRR_m = 0;
1919 	mpsc_shared_regs.MPSC_TCRR_m = 0;
1920 	mpsc_shared_regs.SDMA_INTR_CAUSE_m = 0;
1921 	mpsc_shared_regs.SDMA_INTR_MASK_m = 0;
1922 
1923 	return 0;
1924 }
1925 
1926 static struct platform_driver mpsc_shared_driver = {
1927 	.probe	= mpsc_shared_drv_probe,
1928 	.remove	= mpsc_shared_drv_remove,
1929 	.driver	= {
1930 		.name	= MPSC_SHARED_NAME,
1931 	},
1932 };
1933 
1934 /*
1935  ******************************************************************************
1936  *
1937  * Driver Interface Routines
1938  *
1939  ******************************************************************************
1940  */
1941 static struct uart_driver mpsc_reg = {
1942 	.owner		= THIS_MODULE,
1943 	.driver_name	= MPSC_DRIVER_NAME,
1944 	.dev_name	= MPSC_DEV_NAME,
1945 	.major		= MPSC_MAJOR,
1946 	.minor		= MPSC_MINOR_START,
1947 	.nr		= MPSC_NUM_CTLRS,
1948 	.cons		= MPSC_CONSOLE,
1949 };
1950 
mpsc_drv_map_regs(struct mpsc_port_info * pi,struct platform_device * pd)1951 static int mpsc_drv_map_regs(struct mpsc_port_info *pi,
1952 		struct platform_device *pd)
1953 {
1954 	struct resource	*r;
1955 
1956 	if ((r = platform_get_resource(pd, IORESOURCE_MEM, MPSC_BASE_ORDER))
1957 			&& request_mem_region(r->start, MPSC_REG_BLOCK_SIZE,
1958 			"mpsc_regs")) {
1959 		pi->mpsc_base = ioremap(r->start, MPSC_REG_BLOCK_SIZE);
1960 		pi->mpsc_base_p = r->start;
1961 	} else {
1962 		mpsc_resource_err("MPSC base");
1963 		goto err;
1964 	}
1965 
1966 	if ((r = platform_get_resource(pd, IORESOURCE_MEM,
1967 					MPSC_SDMA_BASE_ORDER))
1968 			&& request_mem_region(r->start,
1969 				MPSC_SDMA_REG_BLOCK_SIZE, "sdma_regs")) {
1970 		pi->sdma_base = ioremap(r->start,MPSC_SDMA_REG_BLOCK_SIZE);
1971 		pi->sdma_base_p = r->start;
1972 	} else {
1973 		mpsc_resource_err("SDMA base");
1974 		goto err;
1975 	}
1976 
1977 	if ((r = platform_get_resource(pd,IORESOURCE_MEM,MPSC_BRG_BASE_ORDER))
1978 			&& request_mem_region(r->start,
1979 				MPSC_BRG_REG_BLOCK_SIZE, "brg_regs")) {
1980 		pi->brg_base = ioremap(r->start, MPSC_BRG_REG_BLOCK_SIZE);
1981 		pi->brg_base_p = r->start;
1982 	} else {
1983 		mpsc_resource_err("BRG base");
1984 		goto err;
1985 	}
1986 	return 0;
1987 
1988 err:
1989 	if (pi->sdma_base) {
1990 		iounmap(pi->sdma_base);
1991 		pi->sdma_base = NULL;
1992 	}
1993 	if (pi->mpsc_base) {
1994 		iounmap(pi->mpsc_base);
1995 		pi->mpsc_base = NULL;
1996 	}
1997 	return -ENOMEM;
1998 }
1999 
mpsc_drv_unmap_regs(struct mpsc_port_info * pi)2000 static void mpsc_drv_unmap_regs(struct mpsc_port_info *pi)
2001 {
2002 	if (pi->mpsc_base) {
2003 		iounmap(pi->mpsc_base);
2004 		release_mem_region(pi->mpsc_base_p, MPSC_REG_BLOCK_SIZE);
2005 	}
2006 	if (pi->sdma_base) {
2007 		iounmap(pi->sdma_base);
2008 		release_mem_region(pi->sdma_base_p, MPSC_SDMA_REG_BLOCK_SIZE);
2009 	}
2010 	if (pi->brg_base) {
2011 		iounmap(pi->brg_base);
2012 		release_mem_region(pi->brg_base_p, MPSC_BRG_REG_BLOCK_SIZE);
2013 	}
2014 
2015 	pi->mpsc_base = NULL;
2016 	pi->sdma_base = NULL;
2017 	pi->brg_base = NULL;
2018 
2019 	pi->mpsc_base_p = 0;
2020 	pi->sdma_base_p = 0;
2021 	pi->brg_base_p = 0;
2022 }
2023 
mpsc_drv_get_platform_data(struct mpsc_port_info * pi,struct platform_device * pd,int num)2024 static void mpsc_drv_get_platform_data(struct mpsc_port_info *pi,
2025 		struct platform_device *pd, int num)
2026 {
2027 	struct mpsc_pdata	*pdata;
2028 
2029 	pdata = dev_get_platdata(&pd->dev);
2030 
2031 	pi->port.uartclk = pdata->brg_clk_freq;
2032 	pi->port.iotype = UPIO_MEM;
2033 	pi->port.line = num;
2034 	pi->port.type = PORT_MPSC;
2035 	pi->port.fifosize = MPSC_TXBE_SIZE;
2036 	pi->port.membase = pi->mpsc_base;
2037 	pi->port.mapbase = (ulong)pi->mpsc_base;
2038 	pi->port.ops = &mpsc_pops;
2039 
2040 	pi->mirror_regs = pdata->mirror_regs;
2041 	pi->cache_mgmt = pdata->cache_mgmt;
2042 	pi->brg_can_tune = pdata->brg_can_tune;
2043 	pi->brg_clk_src = pdata->brg_clk_src;
2044 	pi->mpsc_max_idle = pdata->max_idle;
2045 	pi->default_baud = pdata->default_baud;
2046 	pi->default_bits = pdata->default_bits;
2047 	pi->default_parity = pdata->default_parity;
2048 	pi->default_flow = pdata->default_flow;
2049 
2050 	/* Initial values of mirrored regs */
2051 	pi->MPSC_CHR_1_m = pdata->chr_1_val;
2052 	pi->MPSC_CHR_2_m = pdata->chr_2_val;
2053 	pi->MPSC_CHR_10_m = pdata->chr_10_val;
2054 	pi->MPSC_MPCR_m = pdata->mpcr_val;
2055 	pi->BRG_BCR_m = pdata->bcr_val;
2056 
2057 	pi->shared_regs = &mpsc_shared_regs;
2058 
2059 	pi->port.irq = platform_get_irq(pd, 0);
2060 }
2061 
mpsc_drv_probe(struct platform_device * dev)2062 static int mpsc_drv_probe(struct platform_device *dev)
2063 {
2064 	struct mpsc_port_info *pi;
2065 	int rc;
2066 
2067 	dev_dbg(&dev->dev, "mpsc_drv_probe: Adding MPSC %d\n", dev->id);
2068 
2069 	if (dev->id >= MPSC_NUM_CTLRS)
2070 		return -ENODEV;
2071 
2072 	pi = &mpsc_ports[dev->id];
2073 
2074 	rc = mpsc_drv_map_regs(pi, dev);
2075 	if (rc)
2076 		return rc;
2077 
2078 	mpsc_drv_get_platform_data(pi, dev, dev->id);
2079 	pi->port.dev = &dev->dev;
2080 
2081 	rc = mpsc_make_ready(pi);
2082 	if (rc)
2083 		goto err_unmap;
2084 
2085 	spin_lock_init(&pi->tx_lock);
2086 	rc = uart_add_one_port(&mpsc_reg, &pi->port);
2087 	if (rc)
2088 		goto err_relport;
2089 
2090 	return 0;
2091 err_relport:
2092 	mpsc_release_port(&pi->port);
2093 err_unmap:
2094 	mpsc_drv_unmap_regs(pi);
2095 	return rc;
2096 }
2097 
2098 static struct platform_driver mpsc_driver = {
2099 	.probe	= mpsc_drv_probe,
2100 	.driver	= {
2101 		.name			= MPSC_CTLR_NAME,
2102 		.suppress_bind_attrs	= true,
2103 	},
2104 };
2105 
mpsc_drv_init(void)2106 static int __init mpsc_drv_init(void)
2107 {
2108 	int	rc;
2109 
2110 	printk(KERN_INFO "Serial: MPSC driver\n");
2111 
2112 	memset(mpsc_ports, 0, sizeof(mpsc_ports));
2113 	memset(&mpsc_shared_regs, 0, sizeof(mpsc_shared_regs));
2114 
2115 	rc = uart_register_driver(&mpsc_reg);
2116 	if (rc)
2117 		return rc;
2118 
2119 	rc = platform_driver_register(&mpsc_shared_driver);
2120 	if (rc)
2121 		goto err_unreg_uart;
2122 
2123 	rc = platform_driver_register(&mpsc_driver);
2124 	if (rc)
2125 		goto err_unreg_plat;
2126 
2127 	return 0;
2128 err_unreg_plat:
2129 	platform_driver_unregister(&mpsc_shared_driver);
2130 err_unreg_uart:
2131 	uart_unregister_driver(&mpsc_reg);
2132 	return rc;
2133 }
2134 device_initcall(mpsc_drv_init);
2135 
2136 /*
2137 MODULE_AUTHOR("Mark A. Greer <mgreer@mvista.com>");
2138 MODULE_DESCRIPTION("Generic Marvell MPSC serial/UART driver");
2139 MODULE_LICENSE("GPL");
2140 */
2141