soc/mediatek/mt8196: Add NOR-Flash support

Add NOR-Flash drivers for flash read/write.

TEST=read nor flash data successfully.
BUG=b:317009620

Change-Id: Id0a19f0520020f16c4cf9d62da4228a5b0371b91
Signed-off-by: Jarried Lin <jarried.lin@mediatek.corp-partner.google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/83923
Reviewed-by: Yu-Ping Wu <yupingso@google.com>
Reviewed-by: Yidi Lin <yidilin@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/soc/mediatek/mt8196/Kconfig

@@ -9,6 +9,7 @@ config SOC_MEDIATEK_MT8196
 	select ARCH_RAMSTAGE_ARMV8_64
 	select HAVE_UART_SPECIAL
 	select SOC_MEDIATEK_COMMON
+	select FLASH_DUAL_IO_READ
 	select ARM64_USE_ARCH_TIMER
 
 if SOC_MEDIATEK_MT8196

src/soc/mediatek/mt8196/Makefile.mk

@@ -2,6 +2,7 @@
 
 ifeq ($(CONFIG_SOC_MEDIATEK_MT8196),y)
 
+all-y += ../common/flash_controller.c
 all-y += ../common/gpio.c ../common/gpio_op.c gpio.c
 all-$(CONFIG_SPI_FLASH) += spi.c
 all-y += timer.c

src/soc/mediatek/mt8196/include/soc/spi.h

@@ -10,4 +10,7 @@
 
 #include <spi-generic.h>
 
+/* Initialize SPI NOR Flash Controller */
+void mtk_snfc_init(void);
+
 #endif

src/soc/mediatek/mt8196/spi.c

@@ -6,16 +6,37 @@
  */
 
 #include <device/mmio.h>
+#include <gpio.h>
 #include <soc/addressmap.h>
+#include <soc/flash_controller_common.h>
 #include <soc/spi.h>
+#include <spi_flash.h>
+
+#define PAD_FUNC_SEL(name, func, sel) {GPIO(name), PAD_##name##_FUNC_##func, sel}
+
+static const struct mtk_snfc_pad_func nor_pinmux[4] = {
+	PAD_FUNC_SEL(SDA10, SF_CK, GPIO_PULL_DOWN),
+	PAD_FUNC_SEL(SCL10, SF_CS, GPIO_PULL_UP),
+	PAD_FUNC_SEL(PERIPHERAL_EN5, SF_D0, GPIO_PULL_DOWN),
+	PAD_FUNC_SEL(PERIPHERAL_EN6, SF_D1, GPIO_PULL_DOWN),
+};
+
+void mtk_snfc_init(void)
+{
+	for (size_t i = 0; i < ARRAY_SIZE(nor_pinmux); i++)
+		mtk_snfc_init_pad_func(&nor_pinmux[i], GPIO_DRV_14_MA);
+}
 
 static const struct spi_ctrlr spi_flash_ctrlr = {
 	.max_xfer_size = 65535,
+	.flash_probe = mtk_spi_flash_probe,
 };
 
 const struct spi_ctrlr_buses spi_ctrlr_bus_map[] = {
 	{
 		.ctrlr = &spi_flash_ctrlr,
+		.bus_start = CONFIG_BOOT_DEVICE_SPI_FLASH_BUS,
+		.bus_end = CONFIG_BOOT_DEVICE_SPI_FLASH_BUS,
 	},
 };