1 /*
2 * Driver for CPM (SCC/SMC) serial ports; CPM2 definitions
3 *
4 * Maintainer: Kumar Gala (galak@kernel.crashing.org) (CPM2)
5 * Pantelis Antoniou (panto@intracom.gr) (CPM1)
6 *
7 * Copyright (C) 2004 Freescale Semiconductor, Inc.
8 * (C) 2004 Intracom, S.A.
9 * (C) 2006 MontaVista Software, Inc.
10 * Vitaly Bordug <vbordug@ru.mvista.com>
11 *
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2 of the License, or
15 * (at your option) any later version.
16 *
17 * This program is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU General Public License for more details.
21 *
22 * You should have received a copy of the GNU General Public License
23 * along with this program; if not, write to the Free Software
24 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
25 *
26 */
27
28 #include <linux/module.h>
29 #include <linux/tty.h>
30 #include <linux/ioport.h>
31 #include <linux/slab.h>
32 #include <linux/serial.h>
33 #include <linux/console.h>
34 #include <linux/sysrq.h>
35 #include <linux/device.h>
36 #include <linux/bootmem.h>
37 #include <linux/dma-mapping.h>
38
39 #include <asm/io.h>
40 #include <asm/irq.h>
41 #include <asm/fs_pd.h>
42 #include <asm/prom.h>
43
44 #include <linux/serial_core.h>
45 #include <linux/kernel.h>
46
47 #include "cpm_uart.h"
48
49 /**************************************************************/
50
cpm_line_cr_cmd(struct uart_cpm_port * port,int cmd)51 void cpm_line_cr_cmd(struct uart_cpm_port *port, int cmd)
52 {
53 cpm_command(port->command, cmd);
54 }
55
cpm_uart_map_pram(struct uart_cpm_port * port,struct device_node * np)56 void __iomem *cpm_uart_map_pram(struct uart_cpm_port *port,
57 struct device_node *np)
58 {
59 void __iomem *pram;
60 unsigned long offset;
61 struct resource res;
62 resource_size_t len;
63
64 /* Don't remap parameter RAM if it has already been initialized
65 * during console setup.
66 */
67 if (IS_SMC(port) && port->smcup)
68 return port->smcup;
69 else if (!IS_SMC(port) && port->sccup)
70 return port->sccup;
71
72 if (of_address_to_resource(np, 1, &res))
73 return NULL;
74
75 len = resource_size(&res);
76 pram = ioremap(res.start, len);
77 if (!pram)
78 return NULL;
79
80 if (!IS_SMC(port))
81 return pram;
82
83 if (len != 2) {
84 printk(KERN_WARNING "cpm_uart[%d]: device tree references "
85 "SMC pram, using boot loader/wrapper pram mapping. "
86 "Please fix your device tree to reference the pram "
87 "base register instead.\n",
88 port->port.line);
89 return pram;
90 }
91
92 offset = cpm_dpalloc(PROFF_SMC_SIZE, 64);
93 out_be16(pram, offset);
94 iounmap(pram);
95 return cpm_muram_addr(offset);
96 }
97
cpm_uart_unmap_pram(struct uart_cpm_port * port,void __iomem * pram)98 void cpm_uart_unmap_pram(struct uart_cpm_port *port, void __iomem *pram)
99 {
100 if (!IS_SMC(port))
101 iounmap(pram);
102 }
103
104 /*
105 * Allocate DP-Ram and memory buffers. We need to allocate a transmit and
106 * receive buffer descriptors from dual port ram, and a character
107 * buffer area from host mem. If we are allocating for the console we need
108 * to do it from bootmem
109 */
cpm_uart_allocbuf(struct uart_cpm_port * pinfo,unsigned int is_con)110 int cpm_uart_allocbuf(struct uart_cpm_port *pinfo, unsigned int is_con)
111 {
112 int dpmemsz, memsz;
113 u8 __iomem *dp_mem;
114 unsigned long dp_offset;
115 u8 *mem_addr;
116 dma_addr_t dma_addr = 0;
117
118 pr_debug("CPM uart[%d]:allocbuf\n", pinfo->port.line);
119
120 dpmemsz = sizeof(cbd_t) * (pinfo->rx_nrfifos + pinfo->tx_nrfifos);
121 dp_offset = cpm_dpalloc(dpmemsz, 8);
122 if (IS_ERR_VALUE(dp_offset)) {
123 printk(KERN_ERR
124 "cpm_uart_cpm.c: could not allocate buffer descriptors\n");
125 return -ENOMEM;
126 }
127
128 dp_mem = cpm_dpram_addr(dp_offset);
129
130 memsz = L1_CACHE_ALIGN(pinfo->rx_nrfifos * pinfo->rx_fifosize) +
131 L1_CACHE_ALIGN(pinfo->tx_nrfifos * pinfo->tx_fifosize);
132 if (is_con) {
133 mem_addr = kzalloc(memsz, GFP_NOWAIT);
134 dma_addr = virt_to_bus(mem_addr);
135 }
136 else
137 mem_addr = dma_alloc_coherent(pinfo->port.dev, memsz, &dma_addr,
138 GFP_KERNEL);
139
140 if (mem_addr == NULL) {
141 cpm_dpfree(dp_offset);
142 printk(KERN_ERR
143 "cpm_uart_cpm.c: could not allocate coherent memory\n");
144 return -ENOMEM;
145 }
146
147 pinfo->dp_addr = dp_offset;
148 pinfo->mem_addr = mem_addr;
149 pinfo->dma_addr = dma_addr;
150 pinfo->mem_size = memsz;
151
152 pinfo->rx_buf = mem_addr;
153 pinfo->tx_buf = pinfo->rx_buf + L1_CACHE_ALIGN(pinfo->rx_nrfifos
154 * pinfo->rx_fifosize);
155
156 pinfo->rx_bd_base = (cbd_t __iomem *)dp_mem;
157 pinfo->tx_bd_base = pinfo->rx_bd_base + pinfo->rx_nrfifos;
158
159 return 0;
160 }
161
cpm_uart_freebuf(struct uart_cpm_port * pinfo)162 void cpm_uart_freebuf(struct uart_cpm_port *pinfo)
163 {
164 dma_free_coherent(pinfo->port.dev, L1_CACHE_ALIGN(pinfo->rx_nrfifos *
165 pinfo->rx_fifosize) +
166 L1_CACHE_ALIGN(pinfo->tx_nrfifos *
167 pinfo->tx_fifosize), (void __force *)pinfo->mem_addr,
168 pinfo->dma_addr);
169
170 cpm_dpfree(pinfo->dp_addr);
171 }
172