[coreboot-gerrit] Patch set updated for coreboot: mediatek/mt8173: Provide I2C bus initialization API

[Patrick Georgi (pgeorgi@google.com)]

Patrick Georgi (pgeorgi at google.com) just uploaded a new patch set to gerrit, which you can find at https://review.coreboot.org/13107

-gerrit

commit dce83cb1dee9681c9ee04faaf0c10033a431f65f
Author: jun.gao <jun.gao at mediatek.com>
Date:   Thu Dec 17 16:59:55 2015 +0800

    mediatek/mt8173: Provide I2C bus initialization API
    
    BRANCH=none
    BUG=none
    TEST=build pass and boot to oak kernel
    
    Change-Id: I8aa9ca0fce804cc1682947b7e184781dd5d437f7
    Signed-off-by: Patrick Georgi <pgeorgi at chromium.org>
    Original-Commit-Id: 8641689e008c58e909606c225dddb81dc6457ae9
    Original-Change-Id: I96ef8a36bc70594097e9df964934b7e3eca5d5f9
    Original-Signed-off-by: jun.gao <jun.gao at mediatek.com>
    Original-Reviewed-on: https://chromium-review.googlesource.com/319031
    Original-Commit-Ready: Yidi Lin <yidi.lin at mediatek.com>
    Original-Tested-by: Yidi Lin <yidi.lin at mediatek.com>
    Original-Reviewed-by: Julius Werner <jwerner at chromium.org>
---
 src/soc/mediatek/mt8173/Makefile.inc      |  3 ++-
 src/soc/mediatek/mt8173/i2c.c             | 30 ++++++++++++++++++++----------
 src/soc/mediatek/mt8173/include/soc/i2c.h |  2 ++
 3 files changed, 24 insertions(+), 11 deletions(-)

diff --git a/src/soc/mediatek/mt8173/Makefile.inc b/src/soc/mediatek/mt8173/Makefile.inc
index 54f012a..b35e1f6 100644
--- a/src/soc/mediatek/mt8173/Makefile.inc
+++ b/src/soc/mediatek/mt8173/Makefile.inc
@@ -17,6 +17,7 @@ ifeq ($(CONFIG_SOC_MEDIATEK_MT8173),y)
 
 bootblock-y += bootblock.c
 bootblock-$(CONFIG_SPI_FLASH) += flash_controller.c
+bootblock-y += i2c.c
 bootblock-y += pll.c
 bootblock-y += spi.c
 bootblock-y += timer.c
@@ -64,7 +65,7 @@ ramstage-$(CONFIG_SPI_FLASH) += flash_controller.c
 ramstage-y += soc.c mtcmos.c
 ramstage-y += timer.c
 ramstage-$(CONFIG_DRIVERS_UART) += uart.c
-ramstage-y += pmic_wrap.c mt6391.c
+ramstage-y += pmic_wrap.c mt6391.c i2c.c
 ramstage-y += gpio.c
 ramstage-y += wdt.c
 ramstage-y += pll.c
diff --git a/src/soc/mediatek/mt8173/i2c.c b/src/soc/mediatek/mt8173/i2c.c
index 52b1fb2..6c04ec3 100644
--- a/src/soc/mediatek/mt8173/i2c.c
+++ b/src/soc/mediatek/mt8173/i2c.c
@@ -88,6 +88,26 @@ static inline void i2c_dma_reset(struct mt8173_i2c_dma_regs *dma_regs)
 	udelay(50);
 }
 
+void mtk_i2c_bus_init(uint8_t bus)
+{
+	uint8_t sample_div;
+	uint8_t step_div;
+	uint32_t i2c_freq;
+
+	assert(bus < ARRAY_SIZE(i2c));
+
+	/* Calculate i2c frequency */
+	sample_div = 1;
+	step_div = div_round_up(I2C_CLK_HZ, (400 * KHz * sample_div * 2));
+	i2c_freq = I2C_CLK_HZ / (step_div * sample_div * 2);
+	assert(sample_div < 8 && step_div < 64 && i2c_freq < 400 * KHz &&
+	       i2c_freq >= 380 * KHz);
+
+	/* Init i2c bus Timing register */
+	write32(&i2c[bus].i2c_regs->timing, (sample_div - 1) << 8 |
+					    (step_div - 1));
+}
+
 static inline void mtk_i2c_dump_info(uint8_t bus)
 {
 	struct mt8173_i2c_regs *regs;
@@ -127,9 +147,6 @@ static uint32_t mtk_i2c_transfer(uint8_t bus, struct i2c_seg *seg,
 	uint32_t read_len = 0;
 	uint8_t *write_buffer = NULL;
 	uint8_t *read_buffer = NULL;
-	uint8_t sample_div;
-	uint8_t step_div;
-	uint32_t i2c_freq;
 	struct mt8173_i2c_regs *regs;
 	struct mt8173_i2c_dma_regs *dma_regs;
 	struct stopwatch sw;
@@ -163,13 +180,6 @@ static uint32_t mtk_i2c_transfer(uint8_t bus, struct i2c_seg *seg,
 		break;
 	}
 
-	/* Calculate i2c frequency */
-	sample_div = 1;
-	step_div = div_round_up(I2C_CLK_HZ, (400 * KHz * sample_div * 2));
-	i2c_freq = I2C_CLK_HZ / (step_div * sample_div * 2);
-	assert(sample_div < 8 && i2c_freq < 400 * KHz && i2c_freq >= 380 * KHz);
-	write32(&regs->timing, (sample_div - 1) << 8 | (step_div - 1));
-
 	/* Clear interrupt status */
 	write32(&regs->intr_stat, I2C_TRANSAC_COMP | I2C_ACKERR |
 		I2C_HS_NACKERR);
diff --git a/src/soc/mediatek/mt8173/include/soc/i2c.h b/src/soc/mediatek/mt8173/include/soc/i2c.h
index 2d8a5db..5f46e9c 100644
--- a/src/soc/mediatek/mt8173/include/soc/i2c.h
+++ b/src/soc/mediatek/mt8173/include/soc/i2c.h
@@ -127,4 +127,6 @@ enum {
 	I2C_TRANSFER_INVALID_ARGUMENT = 0xA006
 };
 
+void mtk_i2c_bus_init(uint8_t bus);
+
 #endif /* SOC_MEDIATEK_MT8173_I2C_H */