LXR linux/drivers/firmware/pcdp.c

   1/*
   2 * Parse the EFI PCDP table to locate the console device.
   3 *
   4 * (c) Copyright 2002, 2003, 2004 Hewlett-Packard Development Company, L.P.
   5 *      Khalid Aziz <khalid.aziz@hp.com>
   6 *      Alex Williamson <alex.williamson@hp.com>
   7 *      Bjorn Helgaas <bjorn.helgaas@hp.com>
   8 *
   9 * This program is free software; you can redistribute it and/or modify
  10 * it under the terms of the GNU General Public License version 2 as
  11 * published by the Free Software Foundation.
  12 */
  13
  14#include <linux/acpi.h>
  15#include <linux/console.h>
  16#include <linux/efi.h>
  17#include <linux/serial.h>
  18#include <linux/serial_8250.h>
  19#include <asm/vga.h>
  20#include "pcdp.h"
  21
  22static int __init
  23setup_serial_console(struct pcdp_uart *uart)
  24{
  25#ifdef CONFIG_SERIAL_8250_CONSOLE
  26        int mmio;
  27        static char options[64], *p = options;
  28        char parity;
  29
  30        mmio = (uart->addr.space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY);
  31        p += sprintf(p, "uart8250,%s,0x%llx",
  32                mmio ? "mmio" : "io", uart->addr.address);
  33        if (uart->baud) {
  34                p += sprintf(p, ",%llu", uart->baud);
  35                if (uart->bits) {
  36                        switch (uart->parity) {
  37                            case 0x2: parity = 'e'; break;
  38                            case 0x3: parity = 'o'; break;
  39                            default:  parity = 'n';
  40                        }
  41                        p += sprintf(p, "%c%d", parity, uart->bits);
  42                }
  43        }
  44
  45        add_preferred_console("uart", 8250, &options[9]);
  46        return setup_early_serial8250_console(options);
  47#else
  48        return -ENODEV;
  49#endif
  50}
  51
  52static int __init
  53setup_vga_console(struct pcdp_device *dev)
  54{
  55#if defined(CONFIG_VT) && defined(CONFIG_VGA_CONSOLE)
  56        u8 *if_ptr;
  57
  58        if_ptr = ((u8 *)dev + sizeof(struct pcdp_device));
  59        if (if_ptr[0] == PCDP_IF_PCI) {
  60                struct pcdp_if_pci if_pci;
  61
  62                /* struct copy since ifptr might not be correctly aligned */
  63
  64                memcpy(&if_pci, if_ptr, sizeof(if_pci));
  65
  66                if (if_pci.trans & PCDP_PCI_TRANS_IOPORT)
  67                        vga_console_iobase = if_pci.ioport_tra;
  68
  69                if (if_pci.trans & PCDP_PCI_TRANS_MMIO)
  70                        vga_console_membase = if_pci.mmio_tra;
  71        }
  72
  73        if (efi_mem_type(vga_console_membase + 0xA0000) == EFI_CONVENTIONAL_MEMORY) {
  74                printk(KERN_ERR "PCDP: VGA selected, but frame buffer is not MMIO!\n");
  75                return -ENODEV;
  76        }
  77
  78        conswitchp = &vga_con;
  79        printk(KERN_INFO "PCDP: VGA console\n");
  80        return 0;
  81#else
  82        return -ENODEV;
  83#endif
  84}
  85
  86int __init
  87efi_setup_pcdp_console(char *cmdline)
  88{
  89        struct pcdp *pcdp;
  90        struct pcdp_uart *uart;
  91        struct pcdp_device *dev, *end;
  92        int i, serial = 0;
  93        int rc = -ENODEV;
  94
  95        if (efi.hcdp == EFI_INVALID_TABLE_ADDR)
  96                return -ENODEV;
  97
  98        pcdp = early_memremap(efi.hcdp, 4096);
  99        printk(KERN_INFO "PCDP: v%d at 0x%lx\n", pcdp->rev, efi.hcdp);
 100
 101        if (strstr(cmdline, "console=hcdp")) {
 102                if (pcdp->rev < 3)
 103                        serial = 1;
 104        } else if (strstr(cmdline, "console=")) {
 105                printk(KERN_INFO "Explicit \"console=\"; ignoring PCDP\n");
 106                goto out;
 107        }
 108
 109        if (pcdp->rev < 3 && efi_uart_console_only())
 110                serial = 1;
 111
 112        for (i = 0, uart = pcdp->uart; i < pcdp->num_uarts; i++, uart++) {
 113                if (uart->flags & PCDP_UART_PRIMARY_CONSOLE || serial) {
 114                        if (uart->type == PCDP_CONSOLE_UART) {
 115                                rc = setup_serial_console(uart);
 116                                goto out;
 117                        }
 118                }
 119        }
 120
 121        end = (struct pcdp_device *) ((u8 *) pcdp + pcdp->length);
 122        for (dev = (struct pcdp_device *) (pcdp->uart + pcdp->num_uarts);
 123             dev < end;
 124             dev = (struct pcdp_device *) ((u8 *) dev + dev->length)) {
 125                if (dev->flags & PCDP_PRIMARY_CONSOLE) {
 126                        if (dev->type == PCDP_CONSOLE_VGA) {
 127                                rc = setup_vga_console(dev);
 128                                goto out;
 129                        }
 130                }
 131        }
 132
 133out:
 134        early_memunmap(pcdp, 4096);
 135        return rc;
 136}
 137