1 /* SPDX-License-Identifier: GPL-2.0-only */
2
3 #include <bootblock_common.h>
4 #include <soc/soc.h>
5 #include <soc/spi.h>
6 #include <soc/uart.h>
7 #include <soc/gpio.h>
8 #include <spi_flash.h>
9 #include <console/console.h>
10 #include <fmap.h>
11 #include "mainboard.h"
12
bootblock_mainboard_early_init(void)13 void bootblock_mainboard_early_init(void)
14 {
15 /* Route UART0 to CON1 */
16 gpio_output(ELGON_GPIO_UART_SEL, 0);
17
18 /* Turn off error LED */
19 gpio_output(ELGON_GPIO_ERROR_LED, 0);
20
21 if (CONFIG(BOOTBLOCK_CONSOLE)) {
22 if (!uart_is_enabled(CONFIG_UART_FOR_CONSOLE))
23 uart_setup(CONFIG_UART_FOR_CONSOLE, CONFIG_TTYS0_BAUD);
24 }
25 }
26
configure_spi_flash(void)27 static void configure_spi_flash(void)
28 {
29 /* The maximum SPI frequency for error-free transmission is at 30 MHz */
30 spi_init_custom(0, // bus
31 28000000, // speed Hz
32 0, // idle low disabled
33 0, // zero idle cycles between transfers
34 0, // MSB first
35 0, // Chip select 0
36 1); // assert is high
37
38 /* Route SPI to SoC */
39 gpio_output(ELGON_GPIO_SPI_MUX, 1);
40 }
41
42 /**
43 * Handle flash write protection.
44 * This code verifies the write-protection on each boot.
45 * Enabling the write protection does only run on the first boot.
46 * An error is fatal as it breaks the Chain Of Trust.
47 */
protect_ro_rgn_spi_flash(void)48 static void protect_ro_rgn_spi_flash(void)
49 {
50 const struct spi_flash *flash = boot_device_spi_flash();
51 const char *fmapname = "WP_RO";
52 struct region ro_rgn;
53
54 if (fmap_locate_area(fmapname, &ro_rgn)) {
55 printk(BIOS_ERR, "%s: No %s FMAP section.\n", __func__,
56 fmapname);
57 die("Can't verify flash protections!");
58 }
59
60 u8 reg8 = 0;
61 spi_flash_status(flash, ®8);
62
63 /* Check if SRP0 is set and RO region is protected */
64 if (!(reg8 & 0x80) ||
65 spi_flash_is_write_protected(flash, &ro_rgn) != 1) {
66 printk(BIOS_WARNING, "%s: FMAP section %s is not write-protected\n",
67 __func__, fmapname);
68
69 /*
70 * Need to protect flash region :
71 * WP_RO read only and use /WP pin
72 * non-volatile programming
73 */
74 if (spi_flash_set_write_protected(flash, &ro_rgn,
75 SPI_WRITE_PROTECTION_PIN) != 0)
76 die("Failed to write-protect WP_RO region!");
77 }
78 printk(BIOS_INFO, "%s: FMAP section %s is write-protected\n",
79 __func__, fmapname);
80 }
81
bootblock_mainboard_init(void)82 void bootblock_mainboard_init(void)
83 {
84 configure_spi_flash();
85 protect_ro_rgn_spi_flash();
86 }
87