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/config.h>
  15 #include <linux/acpi.h>
  16 #include <linux/console.h>
  17 #include <linux/efi.h>
  18 #include <linux/serial.h>
  19 #include <asm/vga.h>
  20 #include "pcdp.h"
  21
  22 static int __init
  23 setup_serial_console(struct pcdp_uart *uart)
  24 {
  25 #ifdef CONFIG_SERIAL_8250_CONSOLE
  26         int mmio;
  27         static char options[64], *p = options;
  28
  29         mmio = (uart->addr.address_space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY);
  30         p += sprintf(p, "console=uart,%s,0x%lx",
  31                 mmio ? "mmio" : "io", uart->addr.address);
  32         if (uart->baud)
  33                 p += sprintf(p, ",%lu", uart->baud);
  34         if (uart->bits)
  35                 p += sprintf(p, "n%d", uart->bits);
  36
  37         return early_serial_console_init(options);
  38 #else
  39         return -ENODEV;
  40 #endif
  41 }
  42
  43 static int __init
  44 setup_vga_console(struct pcdp_device *dev)
  45 {
  46 #if defined(CONFIG_VT) && defined(CONFIG_VGA_CONSOLE)
  47         u8 *if_ptr;
  48
  49         if_ptr = ((u8 *)dev + sizeof(struct pcdp_device));
  50         if (if_ptr[0] == PCDP_IF_PCI) {
  51                 struct pcdp_if_pci if_pci;
  52
  53                 /* struct copy since ifptr might not be correctly aligned */
  54
  55                 memcpy(&if_pci, if_ptr, sizeof(if_pci));
  56
  57                 if (if_pci.trans & PCDP_PCI_TRANS_IOPORT)
  58                         vga_console_iobase = if_pci.ioport_tra;
  59
  60                 if (if_pci.trans & PCDP_PCI_TRANS_MMIO)
  61                         vga_console_membase = if_pci.mmio_tra;
  62         }
  63
  64         if (efi_mem_type(vga_console_membase + 0xA0000) == EFI_CONVENTIONAL_MEMORY) {
  65                 printk(KERN_ERR "PCDP: VGA selected, but frame buffer is not MMIO!\n");
  66                 return -ENODEV;
  67         }
  68
  69         conswitchp = &vga_con;
  70         printk(KERN_INFO "PCDP: VGA console\n");
  71         return 0;
  72 #else
  73         return -ENODEV;
  74 #endif
  75 }
  76
  77 int __init
  78 efi_setup_pcdp_console(char *cmdline)
  79 {
  80         struct pcdp *pcdp;
  81         struct pcdp_uart *uart;
  82         struct pcdp_device *dev, *end;
  83         int i, serial = 0;
  84
  85         pcdp = efi.hcdp;
  86         if (!pcdp)
  87                 return -ENODEV;
  88
  89         printk(KERN_INFO "PCDP: v%d at 0x%lx\n", pcdp->rev, __pa(pcdp));
  90
  91         if (strstr(cmdline, "console=hcdp")) {
  92                 if (pcdp->rev < 3)
  93                         serial = 1;
  94         } else if (strstr(cmdline, "console=")) {
  95                 printk(KERN_INFO "Explicit \"console=\"; ignoring PCDP\n");
  96                 return -ENODEV;
  97         }
  98
  99         if (pcdp->rev < 3 && efi_uart_console_only())
 100                 serial = 1;
 101
 102         for (i = 0, uart = pcdp->uart; i < pcdp->num_uarts; i++, uart++) {
 103                 if (uart->flags & PCDP_UART_PRIMARY_CONSOLE || serial) {
 104                         if (uart->type == PCDP_CONSOLE_UART) {
 105                                 return setup_serial_console(uart);
 106                         }
 107                 }
 108         }
 109
 110         end = (struct pcdp_device *) ((u8 *) pcdp + pcdp->length);
 111         for (dev = (struct pcdp_device *) (pcdp->uart + pcdp->num_uarts);
 112              dev < end;
 113              dev = (struct pcdp_device *) ((u8 *) dev + dev->length)) {
 114                 if (dev->flags & PCDP_PRIMARY_CONSOLE) {
 115                         if (dev->type == PCDP_CONSOLE_VGA) {
 116                                 return setup_vga_console(dev);
 117                         }
 118                 }
 119         }
 120
 121         return -ENODEV;
 122 }