New patch to review for coreboot: 1e92b47 exynos5420: use speed parameter in i2c_init() for HSI2C

[Gabe Black]

Gabe Black ([e-mail]) just uploaded a new patch set to gerrit, which you can find at http://review.coreboot.org/3701

-gerrit

commit 1e92b473b8e024c3e171fceccaaf9a227293a531
Author: David Hendricks 
Date:   Sat Jun 22 19:40:43 2013 -0700

exynos5420: use speed parameter in i2c_init() for HSI2C

This allows us to set different speeds for each HSI2C bus.

Change-Id: I50cc257aad9ef50025d0837b0516940b956efc02
    Signed-off-by: David Hendricks 
    Signed-off-by: Gabe Black 
---
 src/cpu/samsung/exynos5420/i2c.c | 25 +++++++++----------------
 1 file changed, 9 insertions(+), 16 deletions(-)

diff --git a/src/cpu/samsung/exynos5420/i2c.c b/src/cpu/samsung/exynos5420/i2c.c
index cbe7a79..b16d068 100644
--- a/src/cpu/samsung/exynos5420/i2c.c
+++ b/src/cpu/samsung/exynos5420/i2c.c
@@ -93,11 +93,6 @@

#define HSI2C_SLV_ADDR_MAS(x)		((x & 0x3ff) << 10)

-/* Controller operating frequency, timing values for operation
- * are calculated against this frequency
- */
-#define HSI2C_FS_TX_CLOCK		1000000
-
 /* S3C I2C Controller bits */
 #define I2CSTAT_BSY	0x20	/* Busy bit */
 #define I2CSTAT_NACK	0x01	/* Nack bit */
@@ -244,11 +239,11 @@ static void i2c_ch_init(struct s3c24x0_i2c_bus *bus, int speed, int slaveadd)
    write32(I2C_MODE_MT | I2C_TXRX_ENA, &bus->regs->iicstat);
 }

-static int hsi2c_get_clk_details(struct s3c24x0_i2c_bus *i2c_bus)
+static int hsi2c_get_clk_details(struct s3c24x0_i2c_bus *i2c_bus,
+		unsigned int bus_freq_hz)
 {
    struct exynos5_hsi2c *hsregs = i2c_bus->hsregs;
    unsigned long clkin = clock_get_periph_rate(i2c_bus->periph_id);
-	unsigned int op_clk = HSI2C_FS_TX_CLOCK;
    unsigned int i = 0, utemp0 = 0, utemp1 = 0;
    unsigned int t_ftl_cycle;

@@ -259,7 +254,7 @@ static int hsi2c_get_clk_details(struct s3c24x0_i2c_bus *i2c_bus)
     * uTemp2 = TSCLK_L + TSCLK_H
     */
    t_ftl_cycle = (read32(&hsregs->usi_conf) >> 16) & 0x7;
-	utemp0 = (clkin / op_clk) - 8 - 2 * t_ftl_cycle;
+	utemp0 = (clkin / bus_freq_hz) - 8 - 2 * t_ftl_cycle;

/* CLK_DIV max is 256 */
    for (i = 0; i < 256; i++) {
@@ -274,7 +269,8 @@ static int hsi2c_get_clk_details(struct s3c24x0_i2c_bus *i2c_bus)
    return -1;
 }

-static void hsi2c_ch_init(struct s3c24x0_i2c_bus *i2c_bus)
+static void hsi2c_ch_init(struct s3c24x0_i2c_bus *i2c_bus,
+				unsigned int bus_freq_hz)
 {
    struct exynos5_hsi2c *hsregs = i2c_bus->hsregs;
    unsigned int t_sr_release;
@@ -288,7 +284,7 @@ static void hsi2c_ch_init(struct s3c24x0_i2c_bus *i2c_bus)
    u32 i2c_timing_s3;
    u32 i2c_timing_sla;

-	hsi2c_get_clk_details(i2c_bus);
+	hsi2c_get_clk_details(i2c_bus, bus_freq_hz);

n_clkdiv = i2c_bus->clk_div;
    t_scl_l = i2c_bus->clk_cycle / 2;
@@ -341,7 +337,8 @@ static void i2c_reset(struct s3c24x0_i2c_bus *i2c_bus)
    write32(i2c_ctl, &i2c->usi_ctl);

/* Initialize the configure registers */
-	hsi2c_ch_init(i2c_bus);
+	/* FIXME: This just assumes 100KHz as a default bus freq */
+	hsi2c_ch_init(i2c_bus, 100000);
 }

void i2c_init(unsigned bus_num, int speed, int slaveadd)
@@ -352,12 +349,8 @@ void i2c_init(unsigned bus_num, int speed, int slaveadd)

i2c_reset(i2c);

-	/* FIXME(dhendrix): hsi2c_ch_init doesn't take a speed or slaveadd
-	 * parameter, so we should split it out and call it directly from
-	 * romstage without the unneeded parameters.
-	 */
    if (i2c->is_highspeed)
-		hsi2c_ch_init(i2c);
+		hsi2c_ch_init(i2c, speed);
    else
    	i2c_ch_init(i2c, speed, slaveadd);
 }