soc/mediatek/mt8196: Enable MMU operation for L2C SRAM and DMA

- Turn off L2C SRAM and reconfigure as L2 cache:
  Mediatek SoC uses part of the L2 cache as SRAM before DRAM is ready.
  After DRAM is ready, we should invoke disable_l2c_sram to reconfigure
  the L2C SRAM as L2 cache.

- Configure DMA buffer in DRAM:
  Set DRAM DMA to be non-cacheable to load blob correctly.

TEST=build pass, register(disable_l2c) read ok
BUG=b:317009620

Change-Id: I6a3cb63d3418f085f5d8d08b282dd59ea431c294
Signed-off-by: Jarried Lin <jarried.lin@mediatek.corp-partner.google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/83925
Reviewed-by: Yidi Lin <yidilin@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Yu-Ping Wu <yupingso@google.com>

3 files changed, 51 insertions, 0 deletions

diff --git a/src/soc/mediatek/mt8196/Makefile.mk b/src/soc/mediatek/mt8196/Makefile.mk
index 96aea39986..44fa59e927 100644
--- a/src/soc/mediatek/mt8196/Makefile.mk
+++ b/src/soc/mediatek/mt8196/Makefile.mk
@@ -13,8 +13,12 @@ bootblock-y += ../common/mmu_operations.c
 
 romstage-y += ../common/cbmem.c
 romstage-y += emi.c
+romstage-y += l2c_ops.c
+romstage-y += ../common/mmu_operations.c ../common/mmu_cmops.c
 
 ramstage-y += emi.c
+ramstage-y += l2c_ops.c
+ramstage-y += ../common/mmu_operations.c ../common/mmu_cmops.c
 ramstage-y += soc.c
 
 CPPFLAGS_common += -Isrc/soc/mediatek/mt8196/include
diff --git a/src/soc/mediatek/mt8196/l2c_ops.c b/src/soc/mediatek/mt8196/l2c_ops.c
new file mode 100644
index 0000000000..b51c49cc15
--- /dev/null
+++ b/src/soc/mediatek/mt8196/l2c_ops.c
@@ -0,0 +1,45 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+/*
+ * This file is created based on MT8196 Functional Specification
+ * Chapter number: 9
+ */
+
+#include <device/mmio.h>
+#include <soc/mmu_operations.h>
+
+DEFINE_BIT(MP0_CLUSTER_CFG0_L3_SHARE_FULLNHALF, 0)
+DEFINE_BIT(MP0_CLUSTER_CFG0_L3_SHARE_EN, 1)
+DEFINE_BIT(MP0_CLUSTER_CFG0_L3_SHARE_PRE_EN, 2)
+
+#define MP0_CLUSTER_CFG0	0x0C000060
+#define CLUST_DIS_VAL		0x3
+#define CLUST_DIS_SHIFT		0x4
+
+void mtk_soc_disable_l2c_sram(void)
+{
+	unsigned long v;
+
+	uint32_t *mp0_cluster_cfg0 = (void *)(MP0_CLUSTER_CFG0);
+
+	SET32_BITFIELDS(mp0_cluster_cfg0,
+			MP0_CLUSTER_CFG0_L3_SHARE_EN, 0);
+	dsb();
+
+	__asm__ volatile ("mrs %0, S3_0_C15_C3_5" : "=r" (v));
+	v |= (CLUST_DIS_VAL << CLUST_DIS_SHIFT);
+	__asm__ volatile ("msr S3_0_C15_C3_5, %0" : : "r" (v));
+	dsb();
+
+	do {
+		__asm__ volatile ("mrs %0, S3_0_C15_C3_7" : "=r" (v));
+	} while (((v >> CLUST_DIS_SHIFT) & CLUST_DIS_VAL) != CLUST_DIS_VAL);
+
+	SET32_BITFIELDS(mp0_cluster_cfg0,
+			MP0_CLUSTER_CFG0_L3_SHARE_PRE_EN, 0);
+
+	SET32_BITFIELDS(mp0_cluster_cfg0,
+			MP0_CLUSTER_CFG0_L3_SHARE_FULLNHALF, 0);
+
+	dsb();
+}
diff --git a/src/soc/mediatek/mt8196/soc.c b/src/soc/mediatek/mt8196/soc.c
index b77735ceed..b62c055426 100644
--- a/src/soc/mediatek/mt8196/soc.c
+++ b/src/soc/mediatek/mt8196/soc.c
@@ -2,6 +2,7 @@
 
 #include <device/device.h>
 #include <soc/emi.h>
+#include <soc/mmu_operations.h>
 #include <symbols.h>
 
 static void soc_read_resources(struct device *dev)
@@ -11,6 +12,7 @@ static void soc_read_resources(struct device *dev)
 
 static void soc_init(struct device *dev)
 {
+	mtk_mmu_disable_l2c_sram();
 }
 
 static struct device_operations soc_ops = {