1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2016 Google, Inc
4  */
5 
6 #include <common.h>
7 #include <dm.h>
8 #include <errno.h>
9 #include <fdtdec.h>
10 #include <pch.h>
11 #include <pci.h>
12 #include <asm/global_data.h>
13 #include <asm/intel_regs.h>
14 #include <asm/io.h>
15 #include <asm/lpc_common.h>
16 #include <linux/bitops.h>
17 
18 DECLARE_GLOBAL_DATA_PTR;
19 
20 /* Enable Prefetching and Caching */
enable_spi_prefetch(struct udevice * pch)21 static void enable_spi_prefetch(struct udevice *pch)
22 {
23 	u8 reg8;
24 
25 	dm_pci_read_config8(pch, 0xdc, &reg8);
26 	reg8 &= ~(3 << 2);
27 	reg8 |= (2 << 2); /* Prefetching and Caching Enabled */
28 	dm_pci_write_config8(pch, 0xdc, reg8);
29 }
30 
enable_port80_on_lpc(struct udevice * pch)31 static void enable_port80_on_lpc(struct udevice *pch)
32 {
33 	/* Enable port 80 POST on LPC */
34 	dm_pci_write_config32(pch, PCH_RCBA_BASE, RCB_BASE_ADDRESS | 1);
35 	clrbits_le32(RCB_REG(GCS), 4);
36 }
37 
38 /**
39  * lpc_early_init() - set up LPC serial ports and other early things
40  *
41  * @dev:	LPC device
42  * @return 0 if OK, -ve on error
43  */
lpc_common_early_init(struct udevice * dev)44 int lpc_common_early_init(struct udevice *dev)
45 {
46 	struct udevice *pch = dev->parent;
47 	struct reg_info {
48 		u32 base;
49 		u32 size;
50 	} values[4], *ptr;
51 	int count;
52 	int i;
53 
54 	count = fdtdec_get_int_array_count(gd->fdt_blob, dev_of_offset(dev),
55 			"intel,gen-dec", (u32 *)values,
56 			sizeof(values) / (sizeof(u32)));
57 	if (count < 0)
58 		return -EINVAL;
59 
60 	/* Set COM1/COM2 decode range */
61 	dm_pci_write_config16(pch, LPC_IO_DEC, 0x0010);
62 
63 	/* Enable PS/2 Keyboard/Mouse, EC areas and COM1 */
64 	dm_pci_write_config16(pch, LPC_EN, KBC_LPC_EN | MC_LPC_EN |
65 			      GAMEL_LPC_EN | COMA_LPC_EN);
66 
67 	/* Write all registers but use 0 if we run out of data */
68 	count = count * sizeof(u32) / sizeof(values[0]);
69 	for (i = 0, ptr = values; i < ARRAY_SIZE(values); i++, ptr++) {
70 		u32 reg = 0;
71 
72 		if (i < count)
73 			reg = ptr->base | PCI_COMMAND_IO | (ptr->size << 16);
74 		dm_pci_write_config32(pch, LPC_GENX_DEC(i), reg);
75 	}
76 
77 	enable_spi_prefetch(pch);
78 
79 	/* This is already done in start.S, but let's do it in C */
80 	enable_port80_on_lpc(pch);
81 
82 	return 0;
83 }
84 
lpc_set_spi_protect(struct udevice * dev,int bios_ctrl,bool protect)85 int lpc_set_spi_protect(struct udevice *dev, int bios_ctrl, bool protect)
86 {
87 	uint8_t bios_cntl;
88 
89 	/* Adjust the BIOS write protect and SMM BIOS Write Protect Disable */
90 	dm_pci_read_config8(dev, bios_ctrl, &bios_cntl);
91 	if (protect) {
92 		bios_cntl &= ~BIOS_CTRL_BIOSWE;
93 		bios_cntl |= BIT(5);
94 	} else {
95 		bios_cntl |= BIOS_CTRL_BIOSWE;
96 		bios_cntl &= ~BIT(5);
97 	}
98 	dm_pci_write_config8(dev, bios_ctrl, bios_cntl);
99 
100 	return 0;
101 }
102