src/soc/amd/common/vboot/transfer_buffer.c

/* SPDX-License-Identifier: GPL-2.0-only */

#include <amdblocks/reset.h>
#include <console/cbmem_console.h>
#include <console/console.h>
#include <pc80/mc146818rtc.h>
#include <psp_verstage/psp_transfer.h>
#include <security/vboot/vbnv.h>
#include <security/vboot/symbols.h>
#include <timestamp.h>
#include <2struct.h>

DECLARE_REGION(cbmemc_transfer)

int transfer_buffer_valid(const struct transfer_info_struct *ptr)
{
	if (ptr->magic_val == TRANSFER_MAGIC_VAL && ptr->struct_bytes == sizeof(*ptr))
		return 1;
	else
		return 0;
}

void verify_psp_transfer_buf(void)
{
	if (*(uint32_t *)_vboot2_work == VB2_SHARED_DATA_MAGIC) {
		cmos_write(0x00, CMOS_RECOVERY_BYTE);
		return;
	}

	/*
	 * If CMOS is valid and the system has already been rebooted once, but
	 * still returns here, instead of rebooting to verstage again, assume
	 * that the system is in a reboot loop and halt.
	 */
	if ((!vbnv_cmos_failed()) && cmos_read(CMOS_RECOVERY_BYTE) ==
			CMOS_RECOVERY_MAGIC_VAL)
		die("Error: Reboot into recovery was unsuccessful.  Halting.");

	printk(BIOS_ERR, "VBOOT workbuf not valid.\n");
	printk(BIOS_DEBUG, "Signature: %#08x\n", *(uint32_t *)_vboot2_work);
	cmos_init(0);
	cmos_write(CMOS_RECOVERY_MAGIC_VAL, CMOS_RECOVERY_BYTE);
	warm_reset();
}

void show_psp_transfer_info(void)
{
	struct transfer_info_struct *info = (struct transfer_info_struct *)
			(void *)(uintptr_t)_transfer_buffer;

	if (transfer_buffer_valid(info)) {
		if ((info->psp_info & PSP_INFO_VALID) == 0) {
			printk(BIOS_INFO, "No PSP info found in transfer buffer.\n");
			return;
		}

		printk(BIOS_INFO, "PSP boot mode: %s\n",
				info->psp_info & PSP_INFO_PRODUCTION_MODE ?
				"Production" : "Development");
		printk(BIOS_INFO, "Silicon level: %s\n",
				info->psp_info & PSP_INFO_PRODUCTION_SILICON ?
				"Production" : "Pre-Production");
	}
}

void replay_transfer_buffer_cbmemc(void)
{
	const struct transfer_info_struct *info = (const struct transfer_info_struct *)
		(void *)(uintptr_t)_transfer_buffer;

	void *cbmemc;
	size_t cbmemc_size;

	if (!transfer_buffer_valid(info))
		return;

	if (info->console_offset < sizeof(*info))
		return;

	if (info->timestamp_offset <= info->console_offset)
		return;

	cbmemc_size = info->timestamp_offset - info->console_offset;

	if (info->console_offset + cbmemc_size > info->buffer_size)
		return;

	cbmemc = (void *)((uintptr_t)info + info->console_offset);

	/* Verify the cbmemc transfer buffer is where we expect it to be. */
	if ((void *)_cbmemc_transfer != (void *)cbmemc)
		return;

	if (REGION_SIZE(cbmemc_transfer) != cbmemc_size)
		return;

	/* We need to manually initialize cbmemc so we can fill the new buffer. cbmemc_init()
	 * will also be called later in console_hw_init(), but it will be a no-op. */
	cbmemc_init();
	cbmemc_copy_in(cbmemc, cbmemc_size);
}