drivers/serial/cpm_uart/cpm_uart_cpm1.c

   1 /*
   2  *  linux/drivers/serial/cpm_uart.c
   3  *
   4  *  Driver for CPM (SCC/SMC) serial ports; CPM1 definitions
   5  *
   6  *  Maintainer: Kumar Gala (galak@kernel.crashing.org) (CPM2)
   7  *              Pantelis Antoniou (panto@intracom.gr) (CPM1)
   8  *
   9  *  Copyright (C) 2004 Freescale Semiconductor, Inc.
  10  *            (C) 2004 Intracom, S.A.
  11  *            (C) 2006 MontaVista Software, Inc.
  12  *              Vitaly Bordug <vbordug@ru.mvista.com>
  13  *
  14  * This program is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU General Public License as published by
  16  * the Free Software Foundation; either version 2 of the License, or
  17  * (at your option) any later version.
  18  *
  19  * This program is distributed in the hope that it will be useful,
  20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22  * GNU General Public License for more details.
  23  *
  24  * You should have received a copy of the GNU General Public License
  25  * along with this program; if not, write to the Free Software
  26  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  27  *
  28  */
  29
  30 #include <linux/module.h>
  31 #include <linux/tty.h>
  32 #include <linux/ioport.h>
  33 #include <linux/init.h>
  34 #include <linux/serial.h>
  35 #include <linux/console.h>
  36 #include <linux/sysrq.h>
  37 #include <linux/device.h>
  38 #include <linux/bootmem.h>
  39 #include <linux/dma-mapping.h>
  40
  41 #include <asm/io.h>
  42 #include <asm/irq.h>
  43 #include <asm/fs_pd.h>
  44
  45 #include <linux/serial_core.h>
  46 #include <linux/kernel.h>
  47
  48 #include <linux/of.h>
  49
  50 #include "cpm_uart.h"
  51
  52 /**************************************************************/
  53
  54 void cpm_line_cr_cmd(struct uart_cpm_port *port, int cmd)
  55 {
  56         cpm_command(port->command, cmd);
  57 }
  58
  59 void __iomem *cpm_uart_map_pram(struct uart_cpm_port *port,
  60                                 struct device_node *np)
  61 {
  62         return of_iomap(np, 1);
  63 }
  64
  65 void cpm_uart_unmap_pram(struct uart_cpm_port *port, void __iomem *pram)
  66 {
  67         iounmap(pram);
  68 }
  69
  70 /*
  71  * Allocate DP-Ram and memory buffers. We need to allocate a transmit and
  72  * receive buffer descriptors from dual port ram, and a character
  73  * buffer area from host mem. If we are allocating for the console we need
  74  * to do it from bootmem
  75  */
  76 int cpm_uart_allocbuf(struct uart_cpm_port *pinfo, unsigned int is_con)
  77 {
  78         int dpmemsz, memsz;
  79         u8 *dp_mem;
  80         unsigned long dp_offset;
  81         u8 *mem_addr;
  82         dma_addr_t dma_addr = 0;
  83
  84         pr_debug("CPM uart[%d]:allocbuf\n", pinfo->port.line);
  85
  86         dpmemsz = sizeof(cbd_t) * (pinfo->rx_nrfifos + pinfo->tx_nrfifos);
  87         dp_offset = cpm_dpalloc(dpmemsz, 8);
  88         if (IS_ERR_VALUE(dp_offset)) {
  89                 printk(KERN_ERR
  90                        "cpm_uart_cpm1.c: could not allocate buffer descriptors\n");
  91                 return -ENOMEM;
  92         }
  93         dp_mem = cpm_dpram_addr(dp_offset);
  94
  95         memsz = L1_CACHE_ALIGN(pinfo->rx_nrfifos * pinfo->rx_fifosize) +
  96             L1_CACHE_ALIGN(pinfo->tx_nrfifos * pinfo->tx_fifosize);
  97         if (is_con) {
  98                 /* was hostalloc but changed cause it blows away the */
  99                 /* large tlb mapping when pinning the kernel area    */
 100                 mem_addr = (u8 *) cpm_dpram_addr(cpm_dpalloc(memsz, 8));
 101                 dma_addr = (u32)cpm_dpram_phys(mem_addr);
 102         } else
 103                 mem_addr = dma_alloc_coherent(pinfo->port.dev, memsz, &dma_addr,
 104                                               GFP_KERNEL);
 105
 106         if (mem_addr == NULL) {
 107                 cpm_dpfree(dp_offset);
 108                 printk(KERN_ERR
 109                        "cpm_uart_cpm1.c: could not allocate coherent memory\n");
 110                 return -ENOMEM;
 111         }
 112
 113         pinfo->dp_addr = dp_offset;
 114         pinfo->mem_addr = mem_addr;             /*  virtual address*/
 115         pinfo->dma_addr = dma_addr;             /*  physical address*/
 116         pinfo->mem_size = memsz;
 117
 118         pinfo->rx_buf = mem_addr;
 119         pinfo->tx_buf = pinfo->rx_buf + L1_CACHE_ALIGN(pinfo->rx_nrfifos
 120                                                        * pinfo->rx_fifosize);
 121
 122         pinfo->rx_bd_base = (cbd_t __iomem __force *)dp_mem;
 123         pinfo->tx_bd_base = pinfo->rx_bd_base + pinfo->rx_nrfifos;
 124
 125         return 0;
 126 }
 127
 128 void cpm_uart_freebuf(struct uart_cpm_port *pinfo)
 129 {
 130         dma_free_coherent(pinfo->port.dev, L1_CACHE_ALIGN(pinfo->rx_nrfifos *
 131                                                           pinfo->rx_fifosize) +
 132                           L1_CACHE_ALIGN(pinfo->tx_nrfifos *
 133                                          pinfo->tx_fifosize), pinfo->mem_addr,
 134                           pinfo->dma_addr);
 135
 136         cpm_dpfree(pinfo->dp_addr);
 137 }