soc/mediatek/mt8192: initialize DFD

DFD (Design for Debug) is a debugging tool, which scans
flip-flops and dumps to internal RAM on the WDT reset.
After system reboots, those values could be showed for
debugging.

Signed-off-by: Rex-BC Chen <rex-bc.chen@mediatek.com>
Change-Id: I39a4391c1d1e832d77b709f8f899bb1c6dcacd69
Reviewed-on: https://review.coreboot.org/c/coreboot/+/56797
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Yu-Ping Wu <yupingso@google.com>

src/soc/mediatek/mt8192/Kconfig

@@ -63,4 +63,10 @@ config SRCLKEN_RC_SUPPORT
 	  This option enables clock buffer remote controller module
 	  to control PMIC 26MHz clock output.
 
+config MTK_DFD
+	bool
+	default n
+	help
+	  This option enables DFD (Design for Debug) settings.
+
 endif

src/soc/mediatek/mt8192/Makefile.inc

@@ -46,6 +46,7 @@ ramstage-y += apusys.c
 ramstage-y += ../common/auxadc.c
 ramstage-y += ../common/ddp.c ddp.c
 ramstage-y += devapc.c
+ramstage-y += dfd.c
 ramstage-y += ../common/dpm.c
 ramstage-y += ../common/dsi.c ../common/mtk_mipi_dphy.c
 ramstage-y += ../common/flash_controller.c

src/soc/mediatek/mt8192/dfd.c

@@ -0,0 +1,12 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#include <console/console.h>
+#include <device/mmio.h>
+#include <soc/dfd.h>
+
+void dfd_init(void)
+{
+	printk(BIOS_INFO, "[%s]\n", __func__);
+	setbits32(dfd_cfg, RESET_ON_KEEP_EN);
+	dsb();
+}

src/soc/mediatek/mt8192/include/soc/dfd.h

@@ -0,0 +1,17 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#ifndef SOC_MEDIATEK_MT8192_DFD_H
+#define SOC_MEDIATEK_MT8192_DFD_H
+
+#define CPC_FLOW_CTRL_CFG       0x0C53A814
+#define RESET_ON_KEEP_EN        BIT(17)
+
+/* DFD dump address and size need to be the same as defined in Kernel DTS. */
+#define DFD_DUMP_ADDRESS	0x6A000000
+#define DFD_DUMP_SIZE		(1 * MiB)
+
+static u32 *const dfd_cfg = (void *)CPC_FLOW_CTRL_CFG;
+
+void dfd_init(void);
+
+#endif

src/soc/mediatek/mt8192/soc.c

@@ -1,8 +1,10 @@
 /* SPDX-License-Identifier: GPL-2.0-only */
 
+#include <bootmem.h>
 #include <device/device.h>
 #include <soc/apusys.h>
 #include <soc/devapc.h>
+#include <soc/dfd.h>
 #include <soc/emi.h>
 #include <soc/mcupm.h>
 #include <soc/mmu_operations.h>
@@ -10,6 +12,12 @@
 #include <soc/ufs.h>
 #include <symbols.h>
 
+void bootmem_platform_add_ranges(void)
+{
+	if (CONFIG(MTK_DFD))
+		bootmem_add_range(DFD_DUMP_ADDRESS, DFD_DUMP_SIZE, BM_MEM_RESERVED);
+}
+
 static void soc_read_resources(struct device *dev)
 {
 	ram_resource(dev, 0, (uintptr_t)_dram / KiB, sdram_size() / KiB);
@@ -22,6 +30,8 @@ static void soc_init(struct device *dev)
 	dapc_init();
 	mcupm_init();
 	sspm_init();
+	if (CONFIG(MTK_DFD))
+		dfd_init();
 	ufs_disable_refclk();
 }