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cpm_uart_cpm1.c
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1 /*
2  * Driver for CPM (SCC/SMC) serial ports; CPM1 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/gfp.h>
31 #include <linux/ioport.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 
44 #include <linux/serial_core.h>
45 #include <linux/kernel.h>
46 
47 #include <linux/of.h>
48 
49 #include "cpm_uart.h"
50 
51 /**************************************************************/
52 
54 {
55  cpm_command(port->command, cmd);
56 }
57 
59  struct device_node *np)
60 {
61  return of_iomap(np, 1);
62 }
63 
64 void cpm_uart_unmap_pram(struct uart_cpm_port *port, void __iomem *pram)
65 {
66  iounmap(pram);
67 }
68 
69 /*
70  * Allocate DP-Ram and memory buffers. We need to allocate a transmit and
71  * receive buffer descriptors from dual port ram, and a character
72  * buffer area from host mem. If we are allocating for the console we need
73  * to do it from bootmem
74  */
75 int cpm_uart_allocbuf(struct uart_cpm_port *pinfo, unsigned int is_con)
76 {
77  int dpmemsz, memsz;
78  u8 *dp_mem;
79  unsigned long dp_offset;
80  u8 *mem_addr;
81  dma_addr_t dma_addr = 0;
82 
83  pr_debug("CPM uart[%d]:allocbuf\n", pinfo->port.line);
84 
85  dpmemsz = sizeof(cbd_t) * (pinfo->rx_nrfifos + pinfo->tx_nrfifos);
86  dp_offset = cpm_dpalloc(dpmemsz, 8);
87  if (IS_ERR_VALUE(dp_offset)) {
89  "cpm_uart_cpm1.c: could not allocate buffer descriptors\n");
90  return -ENOMEM;
91  }
92  dp_mem = cpm_dpram_addr(dp_offset);
93 
94  memsz = L1_CACHE_ALIGN(pinfo->rx_nrfifos * pinfo->rx_fifosize) +
95  L1_CACHE_ALIGN(pinfo->tx_nrfifos * pinfo->tx_fifosize);
96  if (is_con) {
97  /* was hostalloc but changed cause it blows away the */
98  /* large tlb mapping when pinning the kernel area */
99  mem_addr = (u8 *) cpm_dpram_addr(cpm_dpalloc(memsz, 8));
100  dma_addr = (u32)cpm_dpram_phys(mem_addr);
101  } else
102  mem_addr = dma_alloc_coherent(pinfo->port.dev, memsz, &dma_addr,
103  GFP_KERNEL);
104 
105  if (mem_addr == NULL) {
106  cpm_dpfree(dp_offset);
108  "cpm_uart_cpm1.c: could not allocate coherent memory\n");
109  return -ENOMEM;
110  }
111 
112  pinfo->dp_addr = dp_offset;
113  pinfo->mem_addr = mem_addr; /* virtual address*/
114  pinfo->dma_addr = dma_addr; /* physical address*/
115  pinfo->mem_size = memsz;
116 
117  pinfo->rx_buf = mem_addr;
118  pinfo->tx_buf = pinfo->rx_buf + L1_CACHE_ALIGN(pinfo->rx_nrfifos
119  * pinfo->rx_fifosize);
120 
121  pinfo->rx_bd_base = (cbd_t __iomem __force *)dp_mem;
122  pinfo->tx_bd_base = pinfo->rx_bd_base + pinfo->rx_nrfifos;
123 
124  return 0;
125 }
126 
128 {
129  dma_free_coherent(pinfo->port.dev, L1_CACHE_ALIGN(pinfo->rx_nrfifos *
130  pinfo->rx_fifosize) +
131  L1_CACHE_ALIGN(pinfo->tx_nrfifos *
132  pinfo->tx_fifosize), pinfo->mem_addr,
133  pinfo->dma_addr);
134 
135  cpm_dpfree(pinfo->dp_addr);
136 }