LXR linux/drivers/serial/cpm_uart/cpm_uart

   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
  54void cpm_line_cr_cmd(struct uart_cpm_port *port, int cmd)
  55{
  56        cpm_command(port->command, cmd);
  57}
  58
  59void __iomem *cpm_uart_map_pram(struct uart_cpm_port *port,
  60                                struct device_node *np)
  61{
  62        return of_iomap(np, 1);
  63}
  64
  65void 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 */
  76int 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
 128void 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}
 138