soc/mediatek/mt8195: Add i2c driver support

TEST=write/read EEPROM on MT8195 EVB successfully

Change-Id: Ia26e55512501e9758d7f5543d176730cf30ce03d
Signed-off-by: kewei xu <kewei.xu@mediatek.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/53894
Reviewed-by: Yu-Ping Wu <yupingso@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

3 files changed, 230 insertions, 0 deletions

diff --git a/src/soc/mediatek/mt8195/Makefile.inc b/src/soc/mediatek/mt8195/Makefile.inc
index f848f7bf33..aca3905f24 100644
--- a/src/soc/mediatek/mt8195/Makefile.inc
+++ b/src/soc/mediatek/mt8195/Makefile.inc
@@ -3,6 +3,7 @@ ifeq ($(CONFIG_SOC_MEDIATEK_MT8195),y)
 bootblock-y += bootblock.c
 bootblock-y += ../common/flash_controller.c
 bootblock-y += ../common/gpio.c gpio.c
+bootblock-y += ../common/i2c.c i2c.c
 bootblock-y += ../common/mmu_operations.c
 bootblock-y += ../common/pll.c pll.c
 bootblock-$(CONFIG_SPI_FLASH) += ../common/spi.c spi.c
@@ -12,6 +13,7 @@ bootblock-y += ../common/wdt.c
 
 verstage-y += ../common/flash_controller.c
 verstage-y += ../common/gpio.c gpio.c
+verstage-y += ../common/i2c.c i2c.c
 verstage-$(CONFIG_SPI_FLASH) += ../common/spi.c spi.c
 verstage-y += ../common/timer.c timer.c
 verstage-y += ../common/uart.c
@@ -21,6 +23,7 @@ romstage-y += ../common/cbmem.c
 romstage-y += emi.c
 romstage-y += ../common/flash_controller.c
 romstage-y += ../common/gpio.c gpio.c
+romstage-y += ../common/i2c.c i2c.c
 romstage-y += ../common/pll.c pll.c
 romstage-$(CONFIG_SPI_FLASH) += ../common/spi.c spi.c
 romstage-y += ../common/timer.c timer.c
@@ -35,6 +38,7 @@ romstage-y += ../common/mt6359p.c mt6359p.c
 ramstage-y += emi.c
 ramstage-y += ../common/flash_controller.c
 ramstage-y += ../common/gpio.c gpio.c
+ramstage-y += ../common/i2c.c i2c.c
 ramstage-y += ../common/mmu_operations.c mmu_operations.c
 ramstage-y += ../common/mtcmos.c mtcmos.c
 ramstage-$(CONFIG_SPI_FLASH) += ../common/spi.c spi.c
diff --git a/src/soc/mediatek/mt8195/i2c.c b/src/soc/mediatek/mt8195/i2c.c
new file mode 100644
index 0000000000..648083e7b6
--- /dev/null
+++ b/src/soc/mediatek/mt8195/i2c.c
@@ -0,0 +1,168 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#include <assert.h>
+#include <device/mmio.h>
+#include <soc/pll.h>
+#include <soc/i2c.h>
+#include <soc/gpio.h>
+
+#define I2C_CLK_HZ (UNIVPLL_HZ / 20)
+#define I2C_FULL_DUTY 100
+#define I2C_HALF_DUTY 50
+#define I2C_ADJUSTED_DUTY 50
+#define I2C_FS_START_CON 0x0
+
+struct mtk_i2c mtk_i2c_bus_controller[] = {
+	[0] = {
+		.i2c_regs = (void *)(I2C_BASE),
+		.i2c_dma_regs = (void *)(I2C_DMA_BASE),
+		.mt_i2c_flag = I2C_APDMA_ASYNC,
+	},
+	[1] = {
+		.i2c_regs = (void *)(I2C_BASE + 0x1000),
+		.i2c_dma_regs = (void *)(I2C_DMA_BASE + 0x180),
+		.mt_i2c_flag = I2C_APDMA_ASYNC,
+	},
+	[2] = {
+		.i2c_regs = (void *)(I2C_BASE + 0x2000),
+		.i2c_dma_regs = (void *)(I2C_DMA_BASE + 0x300),
+		.mt_i2c_flag = I2C_APDMA_ASYNC,
+	},
+	[3] = {
+		.i2c_regs = (void *)(I2C_BASE + 0x3000),
+		.i2c_dma_regs = (void *)(I2C_DMA_BASE + 0x400),
+		.mt_i2c_flag = I2C_APDMA_ASYNC,
+	},
+	[4] = {
+		.i2c_regs = (void *)(I2C_BASE + 0x4000),
+		.i2c_dma_regs = (void *)(I2C_DMA_BASE + 0x480),
+		.mt_i2c_flag = I2C_APDMA_ASYNC,
+	},
+	[5] = {
+		.i2c_regs = (void *)(I2C_BASE - 0x100000),
+		.i2c_dma_regs = (void *)(I2C_DMA_BASE + 0x500),
+		.mt_i2c_flag = I2C_APDMA_ASYNC,
+	},
+	[6] = {
+		.i2c_regs = (void *)(I2C_BASE - 0xFF000),
+		.i2c_dma_regs = (void *)(I2C_DMA_BASE + 0x580),
+		.mt_i2c_flag = I2C_APDMA_ASYNC,
+	},
+	[7] = {
+		.i2c_regs = (void *)(I2C_BASE - 0xFE000),
+		.i2c_dma_regs = (void *)(I2C_DMA_BASE + 0x600),
+		.mt_i2c_flag = I2C_APDMA_ASYNC,
+	},
+};
+
+#define I2C_BUS_NUMBER ARRAY_SIZE(mtk_i2c_bus_controller)
+
+struct pad_func {
+	gpio_t gpio;
+	u8 func;
+};
+
+#define PAD_FUNC(name, func) {GPIO(name), PAD_##name##_FUNC_##func}
+
+static const struct pad_func i2c_funcs[I2C_BUS_NUMBER][2] = {
+	[0] = {
+		PAD_FUNC(SDA0, SDA0),
+		PAD_FUNC(SCL0, SCL0),
+	},
+	[1] = {
+		PAD_FUNC(SDA1, SDA1),
+		PAD_FUNC(SCL1, SCL1),
+	},
+	[2] = {
+		PAD_FUNC(SDA2, SDA2),
+		PAD_FUNC(SCL2, SCL2),
+	},
+	[3] = {
+		PAD_FUNC(SDA3, SDA3),
+		PAD_FUNC(SCL3, SCL3),
+	},
+	[4] = {
+		PAD_FUNC(SDA4, SDA4),
+		PAD_FUNC(SCL4, SCL4),
+	},
+	[5] = {
+		PAD_FUNC(HDMIRX_SCL, SCL5),
+		PAD_FUNC(HDMIRX_SDA, SDA5),
+	},
+	[6] = {
+		PAD_FUNC(HDMITX_SCL, SCL6),
+		PAD_FUNC(HDMITX_SDA, SDA6),
+	},
+	[7] = {
+		PAD_FUNC(HDMIRX_HTPLG, SCL7),
+		PAD_FUNC(HDMIRX_PWR5V, SDA7),
+	},
+
+};
+
+static void mtk_i2c_set_gpio_pinmux(uint8_t bus)
+{
+	assert(bus < I2C_BUS_NUMBER);
+
+	const struct pad_func *ptr = i2c_funcs[bus];
+	for (size_t i = 0; i < 2; i++) {
+		gpio_set_mode(ptr[i].gpio, ptr[i].func);
+		if (bus <= I2C4)
+			gpio_set_pull(ptr[i].gpio, GPIO_PULL_ENABLE, GPIO_PULL_UP);
+	}
+}
+
+static void mtk_i2c_speed_init(uint8_t bus)
+{
+	uint8_t step_div;
+	const uint8_t clock_div = 5;
+	const uint8_t sample_div = 1;
+	uint32_t i2c_freq;
+	uint32_t tar_speed = 400;
+	uint32_t tar_speed_high;
+	uint32_t tar_speed_low;
+
+	assert(bus < I2C_BUS_NUMBER);
+
+	/* Adjust ratio of high/low level */
+	tar_speed_high = tar_speed * I2C_HALF_DUTY / I2C_ADJUSTED_DUTY;
+
+	/* Calculate i2c frequency */
+	step_div = DIV_ROUND_UP(I2C_CLK_HZ,
+				(tar_speed_high * KHz * sample_div * 2) * clock_div);
+	i2c_freq = I2C_CLK_HZ / (step_div * sample_div * 2 * clock_div);
+	assert(sample_div < 8 && step_div < 64 &&
+	       i2c_freq <= tar_speed_high * KHz &&
+	       i2c_freq >= (tar_speed_high - 20) * KHz);
+
+	/* Init i2c bus timing register */
+	write32(&mtk_i2c_bus_controller[bus].i2c_regs->timing,
+		(sample_div - 1) << 8 | (step_div - 1));
+
+	/* Adjust ratio of high/low level */
+	tar_speed_low = tar_speed * I2C_HALF_DUTY /
+			(I2C_FULL_DUTY - I2C_ADJUSTED_DUTY);
+
+	/* Calculate i2c frequency */
+	step_div = DIV_ROUND_UP(I2C_CLK_HZ,
+				(tar_speed_low * KHz * sample_div * 2) * clock_div);
+	i2c_freq = I2C_CLK_HZ / (step_div * sample_div * 2 * clock_div);
+	assert(sample_div < 8 && step_div < 64 &&
+	       i2c_freq <= tar_speed_low * KHz &&
+	       i2c_freq >= (tar_speed_low - 20) * KHz);
+	write32(&mtk_i2c_bus_controller[bus].i2c_regs->ltiming,
+		(sample_div - 1) << 6 | (step_div - 1));
+
+	/* Init i2c bus clock_div register */
+	write32(&mtk_i2c_bus_controller[bus].i2c_regs->clock_div,
+		clock_div - 1);
+
+	/* Adjust tSU,STA/tHD,STA/tSU,STO */
+	write32(&mtk_i2c_bus_controller[bus].i2c_regs->ext_conf, I2C_FS_START_CON);
+}
+
+void mtk_i2c_bus_init(uint8_t bus)
+{
+	mtk_i2c_speed_init(bus);
+	mtk_i2c_set_gpio_pinmux(bus);
+}
diff --git a/src/soc/mediatek/mt8195/include/soc/i2c.h b/src/soc/mediatek/mt8195/include/soc/i2c.h
new file mode 100644
index 0000000000..977106e482
--- /dev/null
+++ b/src/soc/mediatek/mt8195/include/soc/i2c.h
@@ -0,0 +1,58 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#ifndef SOC_MEDIATEK_MT8195_I2C_H
+#define SOC_MEDIATEK_MT8195_I2C_H
+
+#include <soc/i2c_common.h>
+
+/* I2C Register */
+struct mt_i2c_regs {
+	uint32_t data_port;
+	uint32_t slave_addr;
+	uint32_t intr_mask;
+	uint32_t intr_stat;
+	uint32_t control;
+	uint32_t transfer_len;
+	uint32_t transac_len;
+	uint32_t delay_len;
+	uint32_t timing;
+	uint32_t start;
+	uint32_t ext_conf;
+	uint32_t ltiming;
+	uint32_t hs;
+	uint32_t io_config;
+	uint32_t fifo_addr_clr;
+	uint32_t reserved0[2];
+	uint32_t transfer_aux_len;
+	uint32_t clock_div;
+	uint32_t time_out;
+	uint32_t softreset;
+	uint32_t reserved1[36];
+	uint32_t debug_stat;
+	uint32_t debug_ctrl;
+	uint32_t reserved2[2];
+	uint32_t fifo_stat;
+	uint32_t fifo_thresh;
+	uint32_t reserved3[932];
+	uint32_t multi_dma;
+	uint32_t reserved4[2];
+	uint32_t rollback;
+};
+
+/* I2C ID Number*/
+enum {
+	I2C0,
+	I2C1,
+	I2C2,
+	I2C3,
+	I2C4,
+	I2C5,
+	I2C6,
+	I2C7,
+};
+
+check_member(mt_i2c_regs, multi_dma, 0xf8c);
+
+void mtk_i2c_bus_init(uint8_t bus);
+
+#endif /* SOC_MEDIATEK_MT8195_I2C_H */