linux/drivers/serial/cpm_uart/cpm_uart_cpm2.c
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   1/*
   2 *  linux/drivers/serial/cpm_uart_cpm2.c
   3 *
   4 *  Driver for CPM (SCC/SMC) serial ports; CPM2 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/slab.h>
  34#include <linux/init.h>
  35#include <linux/serial.h>
  36#include <linux/console.h>
  37#include <linux/sysrq.h>
  38#include <linux/device.h>
  39#include <linux/bootmem.h>
  40#include <linux/dma-mapping.h>
  41
  42#include <asm/io.h>
  43#include <asm/irq.h>
  44#include <asm/fs_pd.h>
  45#include <asm/prom.h>
  46
  47#include <linux/serial_core.h>
  48#include <linux/kernel.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        void __iomem *pram;
  63        unsigned long offset;
  64        struct resource res;
  65        resource_size_t len;
  66
  67        /* Don't remap parameter RAM if it has already been initialized
  68         * during console setup.
  69         */
  70        if (IS_SMC(port) && port->smcup)
  71                return port->smcup;
  72        else if (!IS_SMC(port) && port->sccup)
  73                return port->sccup;
  74
  75        if (of_address_to_resource(np, 1, &res))
  76                return NULL;
  77
  78        len = resource_size(&res);
  79        pram = ioremap(res.start, len);
  80        if (!pram)
  81                return NULL;
  82
  83        if (!IS_SMC(port))
  84                return pram;
  85
  86        if (len != 2) {
  87                printk(KERN_WARNING "cpm_uart[%d]: device tree references "
  88                        "SMC pram, using boot loader/wrapper pram mapping. "
  89                        "Please fix your device tree to reference the pram "
  90                        "base register instead.\n",
  91                        port->port.line);
  92                return pram;
  93        }
  94
  95        offset = cpm_dpalloc(PROFF_SMC_SIZE, 64);
  96        out_be16(pram, offset);
  97        iounmap(pram);
  98        return cpm_muram_addr(offset);
  99}
 100
 101void cpm_uart_unmap_pram(struct uart_cpm_port *port, void __iomem *pram)
 102{
 103        if (!IS_SMC(port))
 104                iounmap(pram);
 105}
 106
 107/*
 108 * Allocate DP-Ram and memory buffers. We need to allocate a transmit and
 109 * receive buffer descriptors from dual port ram, and a character
 110 * buffer area from host mem. If we are allocating for the console we need
 111 * to do it from bootmem
 112 */
 113int cpm_uart_allocbuf(struct uart_cpm_port *pinfo, unsigned int is_con)
 114{
 115        int dpmemsz, memsz;
 116        u8 __iomem *dp_mem;
 117        unsigned long dp_offset;
 118        u8 *mem_addr;
 119        dma_addr_t dma_addr = 0;
 120
 121        pr_debug("CPM uart[%d]:allocbuf\n", pinfo->port.line);
 122
 123        dpmemsz = sizeof(cbd_t) * (pinfo->rx_nrfifos + pinfo->tx_nrfifos);
 124        dp_offset = cpm_dpalloc(dpmemsz, 8);
 125        if (IS_ERR_VALUE(dp_offset)) {
 126                printk(KERN_ERR
 127                       "cpm_uart_cpm.c: could not allocate buffer descriptors\n");
 128                return -ENOMEM;
 129        }
 130
 131        dp_mem = cpm_dpram_addr(dp_offset);
 132
 133        memsz = L1_CACHE_ALIGN(pinfo->rx_nrfifos * pinfo->rx_fifosize) +
 134            L1_CACHE_ALIGN(pinfo->tx_nrfifos * pinfo->tx_fifosize);
 135        if (is_con) {
 136                mem_addr = kzalloc(memsz, GFP_NOWAIT);
 137                dma_addr = virt_to_bus(mem_addr);
 138        }
 139        else
 140                mem_addr = dma_alloc_coherent(pinfo->port.dev, memsz, &dma_addr,
 141                                              GFP_KERNEL);
 142
 143        if (mem_addr == NULL) {
 144                cpm_dpfree(dp_offset);
 145                printk(KERN_ERR
 146                       "cpm_uart_cpm.c: could not allocate coherent memory\n");
 147                return -ENOMEM;
 148        }
 149
 150        pinfo->dp_addr = dp_offset;
 151        pinfo->mem_addr = mem_addr;
 152        pinfo->dma_addr = dma_addr;
 153        pinfo->mem_size = memsz;
 154
 155        pinfo->rx_buf = mem_addr;
 156        pinfo->tx_buf = pinfo->rx_buf + L1_CACHE_ALIGN(pinfo->rx_nrfifos
 157                                                       * pinfo->rx_fifosize);
 158
 159        pinfo->rx_bd_base = (cbd_t __iomem *)dp_mem;
 160        pinfo->tx_bd_base = pinfo->rx_bd_base + pinfo->rx_nrfifos;
 161
 162        return 0;
 163}
 164
 165void cpm_uart_freebuf(struct uart_cpm_port *pinfo)
 166{
 167        dma_free_coherent(pinfo->port.dev, L1_CACHE_ALIGN(pinfo->rx_nrfifos *
 168                                                          pinfo->rx_fifosize) +
 169                          L1_CACHE_ALIGN(pinfo->tx_nrfifos *
 170                                         pinfo->tx_fifosize), (void __force *)pinfo->mem_addr,
 171                          pinfo->dma_addr);
 172
 173        cpm_dpfree(pinfo->dp_addr);
 174}
 175