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/init.h>
33 #include <linux/serial.h>
34 #include <linux/console.h>
35 #include <linux/sysrq.h>
36 #include <linux/device.h>
37 #include <linux/bootmem.h>
38 #include <linux/dma-mapping.h>
39
40 #include <asm/io.h>
41 #include <asm/irq.h>
42 #include <asm/fs_pd.h>
43 #include <asm/prom.h>
44
45 #include <linux/serial_core.h>
46 #include <linux/kernel.h>
47
48 #include "cpm_uart.h"
49
50 /**************************************************************/
51
cpm_line_cr_cmd(struct uart_cpm_port * port,int cmd)52 void cpm_line_cr_cmd(struct uart_cpm_port *port, int cmd)
53 {
54 cpm_command(port->command, cmd);
55 }
56
cpm_uart_map_pram(struct uart_cpm_port * port,struct device_node * np)57 void __iomem *cpm_uart_map_pram(struct uart_cpm_port *port,
58 struct device_node *np)
59 {
60 void __iomem *pram;
61 unsigned long offset;
62 struct resource res;
63 resource_size_t len;
64
65 /* Don't remap parameter RAM if it has already been initialized
66 * during console setup.
67 */
68 if (IS_SMC(port) && port->smcup)
69 return port->smcup;
70 else if (!IS_SMC(port) && port->sccup)
71 return port->sccup;
72
73 if (of_address_to_resource(np, 1, &res))
74 return NULL;
75
76 len = resource_size(&res);
77 pram = ioremap(res.start, len);
78 if (!pram)
79 return NULL;
80
81 if (!IS_SMC(port))
82 return pram;
83
84 if (len != 2) {
85 printk(KERN_WARNING "cpm_uart[%d]: device tree references "
86 "SMC pram, using boot loader/wrapper pram mapping. "
87 "Please fix your device tree to reference the pram "
88 "base register instead.\n",
89 port->port.line);
90 return pram;
91 }
92
93 offset = cpm_dpalloc(PROFF_SMC_SIZE, 64);
94 out_be16(pram, offset);
95 iounmap(pram);
96 return cpm_muram_addr(offset);
97 }
98
cpm_uart_unmap_pram(struct uart_cpm_port * port,void __iomem * pram)99 void cpm_uart_unmap_pram(struct uart_cpm_port *port, void __iomem *pram)
100 {
101 if (!IS_SMC(port))
102 iounmap(pram);
103 }
104
105 /*
106 * Allocate DP-Ram and memory buffers. We need to allocate a transmit and
107 * receive buffer descriptors from dual port ram, and a character
108 * buffer area from host mem. If we are allocating for the console we need
109 * to do it from bootmem
110 */
cpm_uart_allocbuf(struct uart_cpm_port * pinfo,unsigned int is_con)111 int cpm_uart_allocbuf(struct uart_cpm_port *pinfo, unsigned int is_con)
112 {
113 int dpmemsz, memsz;
114 u8 __iomem *dp_mem;
115 unsigned long dp_offset;
116 u8 *mem_addr;
117 dma_addr_t dma_addr = 0;
118
119 pr_debug("CPM uart[%d]:allocbuf\n", pinfo->port.line);
120
121 dpmemsz = sizeof(cbd_t) * (pinfo->rx_nrfifos + pinfo->tx_nrfifos);
122 dp_offset = cpm_dpalloc(dpmemsz, 8);
123 if (IS_ERR_VALUE(dp_offset)) {
124 printk(KERN_ERR
125 "cpm_uart_cpm.c: could not allocate buffer descriptors\n");
126 return -ENOMEM;
127 }
128
129 dp_mem = cpm_dpram_addr(dp_offset);
130
131 memsz = L1_CACHE_ALIGN(pinfo->rx_nrfifos * pinfo->rx_fifosize) +
132 L1_CACHE_ALIGN(pinfo->tx_nrfifos * pinfo->tx_fifosize);
133 if (is_con) {
134 mem_addr = kzalloc(memsz, GFP_NOWAIT);
135 dma_addr = virt_to_bus(mem_addr);
136 }
137 else
138 mem_addr = dma_alloc_coherent(pinfo->port.dev, memsz, &dma_addr,
139 GFP_KERNEL);
140
141 if (mem_addr == NULL) {
142 cpm_dpfree(dp_offset);
143 printk(KERN_ERR
144 "cpm_uart_cpm.c: could not allocate coherent memory\n");
145 return -ENOMEM;
146 }
147
148 pinfo->dp_addr = dp_offset;
149 pinfo->mem_addr = mem_addr;
150 pinfo->dma_addr = dma_addr;
151 pinfo->mem_size = memsz;
152
153 pinfo->rx_buf = mem_addr;
154 pinfo->tx_buf = pinfo->rx_buf + L1_CACHE_ALIGN(pinfo->rx_nrfifos
155 * pinfo->rx_fifosize);
156
157 pinfo->rx_bd_base = (cbd_t __iomem *)dp_mem;
158 pinfo->tx_bd_base = pinfo->rx_bd_base + pinfo->rx_nrfifos;
159
160 return 0;
161 }
162
cpm_uart_freebuf(struct uart_cpm_port * pinfo)163 void cpm_uart_freebuf(struct uart_cpm_port *pinfo)
164 {
165 dma_free_coherent(pinfo->port.dev, L1_CACHE_ALIGN(pinfo->rx_nrfifos *
166 pinfo->rx_fifosize) +
167 L1_CACHE_ALIGN(pinfo->tx_nrfifos *
168 pinfo->tx_fifosize), (void __force *)pinfo->mem_addr,
169 pinfo->dma_addr);
170
171 cpm_dpfree(pinfo->dp_addr);
172 }
173