soc/mediatek/mt8186: Support DRAM fast calibration using blob

For most MediaTek SoCs (MT8183, MT8192, MT8195) we rely on an external
program (e.g., the "DRAM blob") to do the full DRAM calibration first,
then store and and apply the generated parameters to the reference
"fast DRAM calibration" in the vendor/mediatek folder for normal system
boot.

Starting with MT8186 the implementation of fast calibration may need
to be changed, and a "DRAM blob" only path is introduced for devices
that have to do both full and fast calibration using the external blob.

TEST=fast calibration pass on kingler/krabby
BUG=b:204226005

Signed-off-by: Xi Chen <xixi.chen@mediatek.corp-partner.google.com>
Change-Id: If25a7dd6aa6261ecff79a1b4df8b1f2e53d896dc
Reviewed-on: https://review.coreboot.org/c/coreboot/+/61133
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Yu-Ping Wu <yupingso@google.com>

2 files changed, 55 insertions, 23 deletions

diff --git a/src/soc/mediatek/common/Kconfig b/src/soc/mediatek/common/Kconfig
index 7d1e4554bc..27f6cec125 100644
--- a/src/soc/mediatek/common/Kconfig
+++ b/src/soc/mediatek/common/Kconfig
@@ -22,6 +22,13 @@ config MEDIATEK_DRAM_DVFS_LIMIT_FREQ_CNT
 	  This options limit DRAM frequency calibration count from total 7 to 3,
 	  other frequency will directly use the low frequency shu result.
 
+config MEDIATEK_BLOB_FAST_INIT
+	bool "Enable running fast calibration by blob"
+	default n
+	help
+	  This option allows performing fast calibration through different
+	  open-source policy.
+
 config MEMORY_TEST
 	bool
 	default y
diff --git a/src/soc/mediatek/common/memory.c b/src/soc/mediatek/common/memory.c
index 1b18dc7210..3ca36117e9 100644
--- a/src/soc/mediatek/common/memory.c
+++ b/src/soc/mediatek/common/memory.c
@@ -4,6 +4,7 @@
 #include <bootmode.h>
 #include <cbfs.h>
 #include <console/console.h>
+#include <soc/dramc_common.h>
 #include <ip_checksum.h>
 #include <mrc_cache.h>
 #include <soc/dramc_param.h>
@@ -95,31 +96,11 @@ const char *get_dram_type_str(u32 ddr_type)
 	return s;
 }
 
-static int dram_run_fast_calibration(struct dramc_param *dparam)
-{
-	const u16 config = CONFIG(MEDIATEK_DRAM_DVFS) ? DRAMC_ENABLE_DVFS : DRAMC_DISABLE_DVFS;
-	if (dparam->dramc_datas.ddr_info.config_dvfs != config) {
-		printk(BIOS_WARNING,
-		       "DRAM-K: Incompatible config for calibration data from flash "
-		       "(expected: %#x, saved: %#x)\n",
-		       config, dparam->dramc_datas.ddr_info.config_dvfs);
-		return -1;
-	}
-
-	printk(BIOS_INFO, "DRAM-K: DRAM calibration data valid pass\n");
-	init_dram_by_params(dparam);
-	if (mt_mem_test(&dparam->dramc_datas) == 0)
-		return 0;
-
-	return DRAMC_ERR_FAST_CALIBRATION;
-}
-
-static int dram_run_full_calibration(struct dramc_param *dparam)
+static int run_dram_blob(struct dramc_param *dparam)
 {
 	/* Load and run the provided blob for full-calibration if available */
 	struct prog dram = PROG_INIT(PROG_REFCODE, CONFIG_CBFS_PREFIX "/dram");
 
-	initialize_dramc_param(dparam);
 	dump_param_header(dparam);
 
 	if (cbfs_prog_stage_load(&dram)) {
@@ -132,12 +113,13 @@ static int dram_run_full_calibration(struct dramc_param *dparam)
 	prog_set_entry(&dram, prog_entry(&dram), dparam);
 	prog_run(&dram);
 	if (dparam->header.status != DRAMC_SUCCESS) {
-		printk(BIOS_ERR, "DRAM-K: Full calibration failed: status = %d\n",
+		printk(BIOS_ERR, "DRAM-K: calibration failed: status = %d\n",
 		       dparam->header.status);
 		return -3;
 	}
 
-	if (!(dparam->header.flags & DRAMC_FLAG_HAS_SAVED_DATA)) {
+	if (!(dparam->header.config & DRAMC_CONFIG_FAST_K)
+	    && !(dparam->header.flags & DRAMC_FLAG_HAS_SAVED_DATA)) {
 		printk(BIOS_ERR,
 		       "DRAM-K: Full calibration executed without saving parameters. "
 		       "Please ensure the blob is built properly.\n");
@@ -147,6 +129,49 @@ static int dram_run_full_calibration(struct dramc_param *dparam)
 	return 0;
 }
 
+static int dram_run_fast_calibration(struct dramc_param *dparam)
+{
+	const u16 config = CONFIG(MEDIATEK_DRAM_DVFS) ? DRAMC_ENABLE_DVFS : DRAMC_DISABLE_DVFS;
+
+	if (dparam->dramc_datas.ddr_info.config_dvfs != config) {
+		printk(BIOS_WARNING,
+		       "DRAM-K: Incompatible config for calibration data from flash "
+		       "(expected: %#x, saved: %#x)\n",
+		       config, dparam->dramc_datas.ddr_info.config_dvfs);
+		return -1;
+	}
+
+	printk(BIOS_INFO, "DRAM-K: DRAM calibration data valid pass\n");
+
+	if (CONFIG(MEDIATEK_BLOB_FAST_INIT)) {
+		printk(BIOS_INFO, "DRAM-K: Run fast calibration run in blob mode\n");
+
+		/*
+		 * The loaded config should not contain FAST_K (done in full calibration),
+		 * so we have to set that now to indicate the blob taking the config instead
+		 * of generating a new config.
+		 */
+		dparam->header.config |= DRAMC_CONFIG_FAST_K;
+
+		if (run_dram_blob(dparam) < 0)
+			return -3;
+	} else {
+		init_dram_by_params(dparam);
+	}
+
+	if (mt_mem_test(&dparam->dramc_datas) < 0)
+		return -4;
+
+	return 0;
+}
+
+static int dram_run_full_calibration(struct dramc_param *dparam)
+{
+	initialize_dramc_param(dparam);
+
+	return run_dram_blob(dparam);
+}
+
 static void mem_init_set_default_config(struct dramc_param *dparam,
 					const struct sdram_info *dram_info)
 {