xref: /openbmc/u-boot/drivers/pch/pch9.c (revision c7c47ca2)
1 /*
2  * Copyright (C) 2014 Google, Inc
3  *
4  * SPDX-License-Identifier:	GPL-2.0+
5  */
6 
7 #include <common.h>
8 #include <dm.h>
9 #include <pch.h>
10 
11 #define GPIO_BASE	0x48
12 #define IO_BASE		0x4c
13 #define SBASE_ADDR	0x54
14 
15 static int pch9_get_spi_base(struct udevice *dev, ulong *sbasep)
16 {
17 	uint32_t sbase_addr;
18 
19 	dm_pci_read_config32(dev, SBASE_ADDR, &sbase_addr);
20 	*sbasep = sbase_addr & 0xfffffe00;
21 
22 	return 0;
23 }
24 
25 static int pch9_get_gpio_base(struct udevice *dev, u32 *gbasep)
26 {
27 	u32 base;
28 
29 	/*
30 	 * GPIO_BASE moved to its current offset with ICH6, but prior to
31 	 * that it was unused (or undocumented). Check that it looks
32 	 * okay: not all ones or zeros.
33 	 *
34 	 * Note we don't need check bit0 here, because the Tunnel Creek
35 	 * GPIO base address register bit0 is reserved (read returns 0),
36 	 * while on the Ivybridge the bit0 is used to indicate it is an
37 	 * I/O space.
38 	 */
39 	dm_pci_read_config32(dev, GPIO_BASE, &base);
40 	if (base == 0x00000000 || base == 0xffffffff) {
41 		debug("%s: unexpected BASE value\n", __func__);
42 		return -ENODEV;
43 	}
44 
45 	/*
46 	 * Okay, I guess we're looking at the right device. The actual
47 	 * GPIO registers are in the PCI device's I/O space, starting
48 	 * at the offset that we just read. Bit 0 indicates that it's
49 	 * an I/O address, not a memory address, so mask that off.
50 	 */
51 	*gbasep = base & 1 ? base & ~3 : base & ~15;
52 
53 	return 0;
54 }
55 
56 static int pch9_get_io_base(struct udevice *dev, u32 *iobasep)
57 {
58 	u32 base;
59 
60 	dm_pci_read_config32(dev, IO_BASE, &base);
61 	if (base == 0x00000000 || base == 0xffffffff) {
62 		debug("%s: unexpected BASE value\n", __func__);
63 		return -ENODEV;
64 	}
65 
66 	*iobasep = base & 1 ? base & ~3 : base & ~15;
67 
68 	return 0;
69 }
70 
71 static const struct pch_ops pch9_ops = {
72 	.get_spi_base	= pch9_get_spi_base,
73 	.get_gpio_base	= pch9_get_gpio_base,
74 	.get_io_base	= pch9_get_io_base,
75 };
76 
77 static const struct udevice_id pch9_ids[] = {
78 	{ .compatible = "intel,pch9" },
79 	{ }
80 };
81 
82 U_BOOT_DRIVER(pch9_drv) = {
83 	.name		= "intel-pch9",
84 	.id		= UCLASS_PCH,
85 	.of_match	= pch9_ids,
86 	.ops		= &pch9_ops,
87 };
88