aboutsummaryrefslogtreecommitdiff
path: root/drivers/firmware/pcdp.c
blob: 4adeb7a2bdf5529bbdc700e97c316c161f066411 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Parse the EFI PCDP table to locate the console device.
 *
 * (c) Copyright 2002, 2003, 2004 Hewlett-Packard Development Company, L.P.
 *	Khalid Aziz <khalid.aziz@hp.com>
 *	Alex Williamson <alex.williamson@hp.com>
 *	Bjorn Helgaas <bjorn.helgaas@hp.com>
 */

#include <linux/acpi.h>
#include <linux/console.h>
#include <linux/efi.h>
#include <linux/serial.h>
#include <linux/serial_core.h>
#include <asm/vga.h>
#include "pcdp.h"

static int __init
setup_serial_console(struct pcdp_uart *uart)
{
#ifdef CONFIG_SERIAL_8250_CONSOLE
	int mmio;
	static char options[64], *p = options;
	char parity;

	mmio = (uart->addr.space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY);
	p += sprintf(p, "uart8250,%s,0x%llx",
		mmio ? "mmio" : "io", uart->addr.address);
	if (uart->baud) {
		p += sprintf(p, ",%llu", uart->baud);
		if (uart->bits) {
			switch (uart->parity) {
			    case 0x2: parity = 'e'; break;
			    case 0x3: parity = 'o'; break;
			    default:  parity = 'n';
			}
			p += sprintf(p, "%c%d", parity, uart->bits);
		}
	}

	add_preferred_console("uart", 8250, &options[9]);
	return setup_earlycon(options);
#else
	return -ENODEV;
#endif
}

static int __init
setup_vga_console(struct pcdp_device *dev)
{
#if defined(CONFIG_VT) && defined(CONFIG_VGA_CONSOLE)
	u8 *if_ptr;

	if_ptr = ((u8 *)dev + sizeof(struct pcdp_device));
	if (if_ptr[0] == PCDP_IF_PCI) {
		struct pcdp_if_pci if_pci;

		/* struct copy since ifptr might not be correctly aligned */

		memcpy(&if_pci, if_ptr, sizeof(if_pci));

		if (if_pci.trans & PCDP_PCI_TRANS_IOPORT)
			vga_console_iobase = if_pci.ioport_tra;

		if (if_pci.trans & PCDP_PCI_TRANS_MMIO)
			vga_console_membase = if_pci.mmio_tra;
	}

	if (efi_mem_type(vga_console_membase + 0xA0000) == EFI_CONVENTIONAL_MEMORY) {
		printk(KERN_ERR "PCDP: VGA selected, but frame buffer is not MMIO!\n");
		return -ENODEV;
	}

	conswitchp = &vga_con;
	printk(KERN_INFO "PCDP: VGA console\n");
	return 0;
#else
	return -ENODEV;
#endif
}

int __init
efi_setup_pcdp_console(char *cmdline)
{
	struct pcdp *pcdp;
	struct pcdp_uart *uart;
	struct pcdp_device *dev, *end;
	int i, serial = 0;
	int rc = -ENODEV;

	if (efi.hcdp == EFI_INVALID_TABLE_ADDR)
		return -ENODEV;

	pcdp = early_memremap(efi.hcdp, 4096);
	printk(KERN_INFO "PCDP: v%d at 0x%lx\n", pcdp->rev, efi.hcdp);

	if (strstr(cmdline, "console=hcdp")) {
		if (pcdp->rev < 3)
			serial = 1;
	} else if (strstr(cmdline, "console=")) {
		printk(KERN_INFO "Explicit \"console=\"; ignoring PCDP\n");
		goto out;
	}

	if (pcdp->rev < 3 && efi_uart_console_only())
		serial = 1;

	for (i = 0, uart = pcdp->uart; i < pcdp->num_uarts; i++, uart++) {
		if (uart->flags & PCDP_UART_PRIMARY_CONSOLE || serial) {
			if (uart->type == PCDP_CONSOLE_UART) {
				rc = setup_serial_console(uart);
				goto out;
			}
		}
	}

	end = (struct pcdp_device *) ((u8 *) pcdp + pcdp->length);
	for (dev = (struct pcdp_device *) (pcdp->uart + pcdp->num_uarts);
	     dev < end;
	     dev = (struct pcdp_device *) ((u8 *) dev + dev->length)) {
		if (dev->flags & PCDP_PRIMARY_CONSOLE) {
			if (dev->type == PCDP_CONSOLE_VGA) {
				rc = setup_vga_console(dev);
				goto out;
			}
		}
	}

out:
	early_memunmap(pcdp, 4096);
	return rc;
}