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 = ioremap(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	iounmap(pcdp);
135	return rc;
136}