1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * (C) 2005, 2006 Red Hat Inc.
4 *
5 * Author: David Woodhouse <dwmw2@infradead.org>
6 * Tom Sylla <tom.sylla@amd.com>
7 *
8 * Overview:
9 * This is a device driver for the NAND flash controller found on
10 * the AMD CS5535/CS5536 companion chipsets for the Geode processor.
11 * mtd-id for command line partitioning is cs553x_nand_cs[0-3]
12 * where 0-3 reflects the chip select for NAND.
13 */
14
15 #include <linux/kernel.h>
16 #include <linux/slab.h>
17 #include <linux/init.h>
18 #include <linux/module.h>
19 #include <linux/delay.h>
20 #include <linux/mtd/mtd.h>
21 #include <linux/mtd/nand-ecc-sw-hamming.h>
22 #include <linux/mtd/rawnand.h>
23 #include <linux/mtd/partitions.h>
24 #include <linux/iopoll.h>
25
26 #include <asm/msr.h>
27
28 #define NR_CS553X_CONTROLLERS 4
29
30 #define MSR_DIVIL_GLD_CAP 0x51400000 /* DIVIL capabilitiies */
31 #define CAP_CS5535 0x2df000ULL
32 #define CAP_CS5536 0x5df500ULL
33
34 /* NAND Timing MSRs */
35 #define MSR_NANDF_DATA 0x5140001b /* NAND Flash Data Timing MSR */
36 #define MSR_NANDF_CTL 0x5140001c /* NAND Flash Control Timing */
37 #define MSR_NANDF_RSVD 0x5140001d /* Reserved */
38
39 /* NAND BAR MSRs */
40 #define MSR_DIVIL_LBAR_FLSH0 0x51400010 /* Flash Chip Select 0 */
41 #define MSR_DIVIL_LBAR_FLSH1 0x51400011 /* Flash Chip Select 1 */
42 #define MSR_DIVIL_LBAR_FLSH2 0x51400012 /* Flash Chip Select 2 */
43 #define MSR_DIVIL_LBAR_FLSH3 0x51400013 /* Flash Chip Select 3 */
44 /* Each made up of... */
45 #define FLSH_LBAR_EN (1ULL<<32)
46 #define FLSH_NOR_NAND (1ULL<<33) /* 1 for NAND */
47 #define FLSH_MEM_IO (1ULL<<34) /* 1 for MMIO */
48 /* I/O BARs have BASE_ADDR in bits 15:4, IO_MASK in 47:36 */
49 /* MMIO BARs have BASE_ADDR in bits 31:12, MEM_MASK in 63:44 */
50
51 /* Pin function selection MSR (IDE vs. flash on the IDE pins) */
52 #define MSR_DIVIL_BALL_OPTS 0x51400015
53 #define PIN_OPT_IDE (1<<0) /* 0 for flash, 1 for IDE */
54
55 /* Registers within the NAND flash controller BAR -- memory mapped */
56 #define MM_NAND_DATA 0x00 /* 0 to 0x7ff, in fact */
57 #define MM_NAND_CTL 0x800 /* Any even address 0x800-0x80e */
58 #define MM_NAND_IO 0x801 /* Any odd address 0x801-0x80f */
59 #define MM_NAND_STS 0x810
60 #define MM_NAND_ECC_LSB 0x811
61 #define MM_NAND_ECC_MSB 0x812
62 #define MM_NAND_ECC_COL 0x813
63 #define MM_NAND_LAC 0x814
64 #define MM_NAND_ECC_CTL 0x815
65
66 /* Registers within the NAND flash controller BAR -- I/O mapped */
67 #define IO_NAND_DATA 0x00 /* 0 to 3, in fact */
68 #define IO_NAND_CTL 0x04
69 #define IO_NAND_IO 0x05
70 #define IO_NAND_STS 0x06
71 #define IO_NAND_ECC_CTL 0x08
72 #define IO_NAND_ECC_LSB 0x09
73 #define IO_NAND_ECC_MSB 0x0a
74 #define IO_NAND_ECC_COL 0x0b
75 #define IO_NAND_LAC 0x0c
76
77 #define CS_NAND_CTL_DIST_EN (1<<4) /* Enable NAND Distract interrupt */
78 #define CS_NAND_CTL_RDY_INT_MASK (1<<3) /* Enable RDY/BUSY# interrupt */
79 #define CS_NAND_CTL_ALE (1<<2)
80 #define CS_NAND_CTL_CLE (1<<1)
81 #define CS_NAND_CTL_CE (1<<0) /* Keep low; 1 to reset */
82
83 #define CS_NAND_STS_FLASH_RDY (1<<3)
84 #define CS_NAND_CTLR_BUSY (1<<2)
85 #define CS_NAND_CMD_COMP (1<<1)
86 #define CS_NAND_DIST_ST (1<<0)
87
88 #define CS_NAND_ECC_PARITY (1<<2)
89 #define CS_NAND_ECC_CLRECC (1<<1)
90 #define CS_NAND_ECC_ENECC (1<<0)
91
92 struct cs553x_nand_controller {
93 struct nand_controller base;
94 struct nand_chip chip;
95 void __iomem *mmio;
96 };
97
98 static struct cs553x_nand_controller *
to_cs553x(struct nand_controller * controller)99 to_cs553x(struct nand_controller *controller)
100 {
101 return container_of(controller, struct cs553x_nand_controller, base);
102 }
103
cs553x_write_ctrl_byte(struct cs553x_nand_controller * cs553x,u32 ctl,u8 data)104 static int cs553x_write_ctrl_byte(struct cs553x_nand_controller *cs553x,
105 u32 ctl, u8 data)
106 {
107 u8 status;
108 int ret;
109
110 writeb(ctl, cs553x->mmio + MM_NAND_CTL);
111 writeb(data, cs553x->mmio + MM_NAND_IO);
112 ret = readb_poll_timeout_atomic(cs553x->mmio + MM_NAND_STS, status,
113 !(status & CS_NAND_CTLR_BUSY), 1,
114 100000);
115 if (ret)
116 return ret;
117
118 return 0;
119 }
120
cs553x_data_in(struct cs553x_nand_controller * cs553x,void * buf,unsigned int len)121 static void cs553x_data_in(struct cs553x_nand_controller *cs553x, void *buf,
122 unsigned int len)
123 {
124 writeb(0, cs553x->mmio + MM_NAND_CTL);
125 while (unlikely(len > 0x800)) {
126 memcpy_fromio(buf, cs553x->mmio, 0x800);
127 buf += 0x800;
128 len -= 0x800;
129 }
130 memcpy_fromio(buf, cs553x->mmio, len);
131 }
132
cs553x_data_out(struct cs553x_nand_controller * cs553x,const void * buf,unsigned int len)133 static void cs553x_data_out(struct cs553x_nand_controller *cs553x,
134 const void *buf, unsigned int len)
135 {
136 writeb(0, cs553x->mmio + MM_NAND_CTL);
137 while (unlikely(len > 0x800)) {
138 memcpy_toio(cs553x->mmio, buf, 0x800);
139 buf += 0x800;
140 len -= 0x800;
141 }
142 memcpy_toio(cs553x->mmio, buf, len);
143 }
144
cs553x_wait_ready(struct cs553x_nand_controller * cs553x,unsigned int timeout_ms)145 static int cs553x_wait_ready(struct cs553x_nand_controller *cs553x,
146 unsigned int timeout_ms)
147 {
148 u8 mask = CS_NAND_CTLR_BUSY | CS_NAND_STS_FLASH_RDY;
149 u8 status;
150
151 return readb_poll_timeout(cs553x->mmio + MM_NAND_STS, status,
152 (status & mask) == CS_NAND_STS_FLASH_RDY, 100,
153 timeout_ms * 1000);
154 }
155
cs553x_exec_instr(struct cs553x_nand_controller * cs553x,const struct nand_op_instr * instr)156 static int cs553x_exec_instr(struct cs553x_nand_controller *cs553x,
157 const struct nand_op_instr *instr)
158 {
159 unsigned int i;
160 int ret = 0;
161
162 switch (instr->type) {
163 case NAND_OP_CMD_INSTR:
164 ret = cs553x_write_ctrl_byte(cs553x, CS_NAND_CTL_CLE,
165 instr->ctx.cmd.opcode);
166 break;
167
168 case NAND_OP_ADDR_INSTR:
169 for (i = 0; i < instr->ctx.addr.naddrs; i++) {
170 ret = cs553x_write_ctrl_byte(cs553x, CS_NAND_CTL_ALE,
171 instr->ctx.addr.addrs[i]);
172 if (ret)
173 break;
174 }
175 break;
176
177 case NAND_OP_DATA_IN_INSTR:
178 cs553x_data_in(cs553x, instr->ctx.data.buf.in,
179 instr->ctx.data.len);
180 break;
181
182 case NAND_OP_DATA_OUT_INSTR:
183 cs553x_data_out(cs553x, instr->ctx.data.buf.out,
184 instr->ctx.data.len);
185 break;
186
187 case NAND_OP_WAITRDY_INSTR:
188 ret = cs553x_wait_ready(cs553x, instr->ctx.waitrdy.timeout_ms);
189 break;
190 }
191
192 if (instr->delay_ns)
193 ndelay(instr->delay_ns);
194
195 return ret;
196 }
197
cs553x_exec_op(struct nand_chip * this,const struct nand_operation * op,bool check_only)198 static int cs553x_exec_op(struct nand_chip *this,
199 const struct nand_operation *op,
200 bool check_only)
201 {
202 struct cs553x_nand_controller *cs553x = to_cs553x(this->controller);
203 unsigned int i;
204 int ret;
205
206 if (check_only)
207 return true;
208
209 /* De-assert the CE pin */
210 writeb(0, cs553x->mmio + MM_NAND_CTL);
211 for (i = 0; i < op->ninstrs; i++) {
212 ret = cs553x_exec_instr(cs553x, &op->instrs[i]);
213 if (ret)
214 break;
215 }
216
217 /* Re-assert the CE pin. */
218 writeb(CS_NAND_CTL_CE, cs553x->mmio + MM_NAND_CTL);
219
220 return ret;
221 }
222
cs_enable_hwecc(struct nand_chip * this,int mode)223 static void cs_enable_hwecc(struct nand_chip *this, int mode)
224 {
225 struct cs553x_nand_controller *cs553x = to_cs553x(this->controller);
226
227 writeb(0x07, cs553x->mmio + MM_NAND_ECC_CTL);
228 }
229
cs_calculate_ecc(struct nand_chip * this,const u_char * dat,u_char * ecc_code)230 static int cs_calculate_ecc(struct nand_chip *this, const u_char *dat,
231 u_char *ecc_code)
232 {
233 struct cs553x_nand_controller *cs553x = to_cs553x(this->controller);
234 uint32_t ecc;
235
236 ecc = readl(cs553x->mmio + MM_NAND_STS);
237
238 ecc_code[1] = ecc >> 8;
239 ecc_code[0] = ecc >> 16;
240 ecc_code[2] = ecc >> 24;
241 return 0;
242 }
243
cs553x_ecc_correct(struct nand_chip * chip,unsigned char * buf,unsigned char * read_ecc,unsigned char * calc_ecc)244 static int cs553x_ecc_correct(struct nand_chip *chip,
245 unsigned char *buf,
246 unsigned char *read_ecc,
247 unsigned char *calc_ecc)
248 {
249 return ecc_sw_hamming_correct(buf, read_ecc, calc_ecc,
250 chip->ecc.size, false);
251 }
252
253 static struct cs553x_nand_controller *controllers[4];
254
cs553x_attach_chip(struct nand_chip * chip)255 static int cs553x_attach_chip(struct nand_chip *chip)
256 {
257 if (chip->ecc.engine_type != NAND_ECC_ENGINE_TYPE_ON_HOST)
258 return 0;
259
260 chip->ecc.size = 256;
261 chip->ecc.bytes = 3;
262 chip->ecc.hwctl = cs_enable_hwecc;
263 chip->ecc.calculate = cs_calculate_ecc;
264 chip->ecc.correct = cs553x_ecc_correct;
265 chip->ecc.strength = 1;
266
267 return 0;
268 }
269
270 static const struct nand_controller_ops cs553x_nand_controller_ops = {
271 .exec_op = cs553x_exec_op,
272 .attach_chip = cs553x_attach_chip,
273 };
274
cs553x_init_one(int cs,int mmio,unsigned long adr)275 static int __init cs553x_init_one(int cs, int mmio, unsigned long adr)
276 {
277 struct cs553x_nand_controller *controller;
278 int err = 0;
279 struct nand_chip *this;
280 struct mtd_info *new_mtd;
281
282 pr_notice("Probing CS553x NAND controller CS#%d at %sIO 0x%08lx\n",
283 cs, mmio ? "MM" : "P", adr);
284
285 if (!mmio) {
286 pr_notice("PIO mode not yet implemented for CS553X NAND controller\n");
287 return -ENXIO;
288 }
289
290 /* Allocate memory for MTD device structure and private data */
291 controller = kzalloc(sizeof(*controller), GFP_KERNEL);
292 if (!controller) {
293 err = -ENOMEM;
294 goto out;
295 }
296
297 this = &controller->chip;
298 nand_controller_init(&controller->base);
299 controller->base.ops = &cs553x_nand_controller_ops;
300 this->controller = &controller->base;
301 new_mtd = nand_to_mtd(this);
302
303 /* Link the private data with the MTD structure */
304 new_mtd->owner = THIS_MODULE;
305
306 /* map physical address */
307 controller->mmio = ioremap(adr, 4096);
308 if (!controller->mmio) {
309 pr_warn("ioremap cs553x NAND @0x%08lx failed\n", adr);
310 err = -EIO;
311 goto out_mtd;
312 }
313
314 /* Enable the following for a flash based bad block table */
315 this->bbt_options = NAND_BBT_USE_FLASH;
316
317 new_mtd->name = kasprintf(GFP_KERNEL, "cs553x_nand_cs%d", cs);
318 if (!new_mtd->name) {
319 err = -ENOMEM;
320 goto out_ior;
321 }
322
323 /* Scan to find existence of the device */
324 err = nand_scan(this, 1);
325 if (err)
326 goto out_free;
327
328 controllers[cs] = controller;
329 goto out;
330
331 out_free:
332 kfree(new_mtd->name);
333 out_ior:
334 iounmap(controller->mmio);
335 out_mtd:
336 kfree(controller);
337 out:
338 return err;
339 }
340
is_geode(void)341 static int is_geode(void)
342 {
343 /* These are the CPUs which will have a CS553[56] companion chip */
344 if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
345 boot_cpu_data.x86 == 5 &&
346 boot_cpu_data.x86_model == 10)
347 return 1; /* Geode LX */
348
349 if ((boot_cpu_data.x86_vendor == X86_VENDOR_NSC ||
350 boot_cpu_data.x86_vendor == X86_VENDOR_CYRIX) &&
351 boot_cpu_data.x86 == 5 &&
352 boot_cpu_data.x86_model == 5)
353 return 1; /* Geode GX (née GX2) */
354
355 return 0;
356 }
357
cs553x_init(void)358 static int __init cs553x_init(void)
359 {
360 int err = -ENXIO;
361 int i;
362 uint64_t val;
363
364 /* If the CPU isn't a Geode GX or LX, abort */
365 if (!is_geode())
366 return -ENXIO;
367
368 /* If it doesn't have the CS553[56], abort */
369 rdmsrl(MSR_DIVIL_GLD_CAP, val);
370 val &= ~0xFFULL;
371 if (val != CAP_CS5535 && val != CAP_CS5536)
372 return -ENXIO;
373
374 /* If it doesn't have the NAND controller enabled, abort */
375 rdmsrl(MSR_DIVIL_BALL_OPTS, val);
376 if (val & PIN_OPT_IDE) {
377 pr_info("CS553x NAND controller: Flash I/O not enabled in MSR_DIVIL_BALL_OPTS.\n");
378 return -ENXIO;
379 }
380
381 for (i = 0; i < NR_CS553X_CONTROLLERS; i++) {
382 rdmsrl(MSR_DIVIL_LBAR_FLSH0 + i, val);
383
384 if ((val & (FLSH_LBAR_EN|FLSH_NOR_NAND)) == (FLSH_LBAR_EN|FLSH_NOR_NAND))
385 err = cs553x_init_one(i, !!(val & FLSH_MEM_IO), val & 0xFFFFFFFF);
386 }
387
388 /* Register all devices together here. This means we can easily hack it to
389 do mtdconcat etc. if we want to. */
390 for (i = 0; i < NR_CS553X_CONTROLLERS; i++) {
391 if (controllers[i]) {
392 /* If any devices registered, return success. Else the last error. */
393 mtd_device_register(nand_to_mtd(&controllers[i]->chip),
394 NULL, 0);
395 err = 0;
396 }
397 }
398
399 return err;
400 }
401
402 module_init(cs553x_init);
403
cs553x_cleanup(void)404 static void __exit cs553x_cleanup(void)
405 {
406 int i;
407
408 for (i = 0; i < NR_CS553X_CONTROLLERS; i++) {
409 struct cs553x_nand_controller *controller = controllers[i];
410 struct nand_chip *this = &controller->chip;
411 struct mtd_info *mtd = nand_to_mtd(this);
412 int ret;
413
414 if (!mtd)
415 continue;
416
417 /* Release resources, unregister device */
418 ret = mtd_device_unregister(mtd);
419 WARN_ON(ret);
420 nand_cleanup(this);
421 kfree(mtd->name);
422 controllers[i] = NULL;
423
424 /* unmap physical address */
425 iounmap(controller->mmio);
426
427 /* Free the MTD device structure */
428 kfree(controller);
429 }
430 }
431
432 module_exit(cs553x_cleanup);
433
434 MODULE_LICENSE("GPL");
435 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
436 MODULE_DESCRIPTION("NAND controller driver for AMD CS5535/CS5536 companion chip");
437