Linux Kernel  3.7.1
 All Data Structures Namespaces Files Functions Variables Typedefs Enumerations Enumerator Macros Groups Pages
cpm_uart_cpm2.c
Go to the documentation of this file.
1 /*
2  * Driver for CPM (SCC/SMC) serial ports; CPM2 definitions
3  *
4  * Maintainer: Kumar Gala ([email protected]) (CPM2)
5  * Pantelis Antoniou ([email protected]) (CPM1)
6  *
7  * Copyright (C) 2004 Freescale Semiconductor, Inc.
8  * (C) 2004 Intracom, S.A.
9  * (C) 2006 MontaVista Software, Inc.
10  * Vitaly Bordug <[email protected]>
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 
53 {
54  cpm_command(port->command, cmd);
55 }
56 
58  struct device_node *np)
59 {
60  void __iomem *pram;
61  unsigned long offset;
62  struct resource res;
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 
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  */
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)) {
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);
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 
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 }