1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Copyright (C) 2017, Bin Meng <bmeng.cn@gmail.com>
4 */
5
6 #include <common.h>
7 #include <asm/io.h>
8
9 #define PCI_DEV_CONFIG(segbus, dev, fn) ( \
10 (((segbus) & 0xfff) << 20) | \
11 (((dev) & 0x1f) << 15) | \
12 (((fn) & 0x07) << 12))
13
14 /* Platform Controller Unit */
15 #define LPC_DEV 0x1f
16 #define LPC_FUNC 0
17
18 /* Enable UART */
19 #define UART_CONT 0x80
20
21 /* UART PAD definitions */
22 #define UART_RXD_COMMUITY 1
23 #define UART_TXD_COMMUITY 1
24 #define UART_RXD_FAMILY 4
25 #define UART_TXD_FAMILY 4
26 #define UART_RXD_PAD 2
27 #define UART_TXD_PAD 7
28 #define UART_RXD_FUNC 3
29 #define UART_TXD_FUNC 3
30
31 /* IO Memory */
32 #define IO_BASE_ADDRESS 0xfed80000
33
gpio_pconf0(int community,int family,int pad)34 static inline uint32_t gpio_pconf0(int community, int family, int pad)
35 {
36 return IO_BASE_ADDRESS + community * 0x8000 + 0x4400 +
37 family * 0x400 + pad * 8;
38 }
39
gpio_select_func(int community,int family,int pad,int func)40 static void gpio_select_func(int community, int family, int pad, int func)
41 {
42 uint32_t pconf0_addr = gpio_pconf0(community, family, pad);
43
44 clrsetbits_le32(pconf0_addr, 0xf << 16, func << 16);
45 }
46
x86_pci_write_config32(int dev,unsigned int where,u32 value)47 static void x86_pci_write_config32(int dev, unsigned int where, u32 value)
48 {
49 unsigned long addr;
50
51 addr = CONFIG_PCIE_ECAM_BASE | dev | (where & ~3);
52 writel(value, addr);
53 }
54
55 /* This can be called after memory-mapped PCI is working */
setup_internal_uart(int enable)56 int setup_internal_uart(int enable)
57 {
58 /* Enable or disable the legacy UART hardware */
59 x86_pci_write_config32(PCI_DEV_CONFIG(0, LPC_DEV, LPC_FUNC), UART_CONT,
60 enable);
61
62 /* All done for the disable part, so just return */
63 if (!enable)
64 return 0;
65
66 /*
67 * Set up the pads to the UART function. This allows the signals to
68 * leave the chip
69 */
70 gpio_select_func(UART_RXD_COMMUITY, UART_RXD_FAMILY,
71 UART_RXD_PAD, UART_RXD_FUNC);
72 gpio_select_func(UART_TXD_COMMUITY, UART_TXD_FAMILY,
73 UART_TXD_PAD, UART_TXD_FUNC);
74
75 return 0;
76 }
77
board_debug_uart_init(void)78 void board_debug_uart_init(void)
79 {
80 setup_internal_uart(1);
81 }
82