drivers/tty/serial/cpm_uart/cpm_uart_cpm1.c

   1 /*
   2  *  Driver for CPM (SCC/SMC) serial ports; CPM1 definitions
   3  *
   4  *  Maintainer: Kumar Gala (galak@kernel.crashing.org) (CPM2)
   5  *              Pantelis Antoniou (panto@intracom.gr) (CPM1)
   6  *
   7  *  Copyright (C) 2004 Freescale Semiconductor, Inc.
   8  *            (C) 2004 Intracom, S.A.
   9  *            (C) 2006 MontaVista Software, Inc.
  10  *              Vitaly Bordug <vbordug@ru.mvista.com>
  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
  53 void cpm_line_cr_cmd(struct uart_cpm_port *port, int cmd)
  54 {
  55         cpm_command(port->command, cmd);
  56 }
  57
  58 void __iomem *cpm_uart_map_pram(struct uart_cpm_port *port,
  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)) {
  88                 printk(KERN_ERR
  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);
 107                 printk(KERN_ERR
 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
 127 void cpm_uart_freebuf(struct uart_cpm_port *pinfo)
 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 }