soc/mediatek/mt8183: Verify checksum of cached calibration data
The checksum is stored in the header of calibration data and saved to
SPI flash. After reading the data from flash, checksum is used to verify
the integrity of the calibration parameters.
BUG=b:139099592
BRANCH=kukui
TEST=Calibration data successfully loaded from flash
Change-Id: Ie4a0688ed6e560d4c0c6b316f44e52fd10d71a9d
Signed-off-by: Yu-Ping Wu <yupingso@chromium.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/36014
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Hung-Te Lin <hungte@chromium.org>
diff --git a/src/soc/mediatek/mt8183/memory.c b/src/soc/mediatek/mt8183/memory.c
index 3d7668d..e48c564 100644
--- a/src/soc/mediatek/mt8183/memory.c
+++ b/src/soc/mediatek/mt8183/memory.c
@@ -16,6 +16,7 @@
#include <assert.h>
#include <cbfs.h>
#include <console/console.h>
+#include <ip_checksum.h>
#include <soc/dramc_param.h>
#include <soc/dramc_pi_api.h>
#include <soc/emi.h>
@@ -70,6 +71,12 @@
printk(BIOS_DEBUG, "header.checksum = %#x\n", header->checksum);
}
+static u32 compute_checksum(const struct dramc_param *dparam)
+{
+ return (u32)compute_ip_checksum(dparam->freq_params,
+ sizeof(dparam->freq_params));
+}
+
static int dram_run_fast_calibration(const struct dramc_param *dparam,
u16 config)
{
@@ -88,6 +95,15 @@
return -1;
}
+ const u32 checksum = compute_checksum(dparam);
+ if (dparam->header.checksum != checksum) {
+ printk(BIOS_ERR,
+ "Invalid DRAM calibration checksum from flash "
+ "(expected: %#x, saved: %#x)\n",
+ checksum, dparam->header.checksum);
+ return -1;
+ }
+
return 0;
}
@@ -165,6 +181,7 @@
printk(BIOS_INFO, "Successfully loaded DRAM blobs and "
"ran DRAM calibration\n");
set_source_to_flash(dparam->freq_params);
+ dparam->header.checksum = compute_checksum(dparam);
dparam_ops->write_to_flash(dparam);
printk(BIOS_DEBUG, "Calibration params saved to flash: "
"version=%#x, size=%#x\n",