allwinner: Use RSB for the PMIC connection on H6

RSB is faster and more efficient, and it has a simpler driver. As long
as the PMIC is returned to I2C mode after use, the rich OS can later use
either bus.

Change-Id: I0c5f32e88a090c8c5cccb81bd24596b301ab9da7
Signed-off-by: Samuel Holland <samuel@sholland.org>

plat/allwinner/common/sunxi_common.c

@@ -125,11 +125,9 @@ int sunxi_init_platform_r_twi(uint16_t socid, bool use_rsb)
 		device_bit = BIT(6);
 		break;
 	case SUNXI_SOC_H6:
-		if (use_rsb)
-			return -ENODEV;
-		pin_func = 0x33;
+		pin_func = use_rsb ? 0x22 : 0x33;
 		device_bit = BIT(16);
-		reset_offset = 0x19c;
+		reset_offset = use_rsb ? 0x1bc : 0x19c;
 		break;
 	case SUNXI_SOC_A64:
 		pin_func = use_rsb ? 0x22 : 0x33;
@@ -157,7 +155,7 @@ int sunxi_init_platform_r_twi(uint16_t socid, bool use_rsb)
 	if (socid != SUNXI_SOC_H6)
 		mmio_setbits_32(SUNXI_R_PRCM_BASE + 0x28, device_bit);
 	else
-		mmio_setbits_32(SUNXI_R_PRCM_BASE + 0x19c, device_bit | BIT(0));
+		mmio_setbits_32(SUNXI_R_PRCM_BASE + reset_offset, BIT(0));
 
 	/* assert, then de-assert reset of I2C/RSB controller */
 	mmio_clrbits_32(SUNXI_R_PRCM_BASE + reset_offset, device_bit);

plat/allwinner/sun50i_h6/include/sunxi_mmap.h

@@ -55,6 +55,7 @@
 #define SUNXI_R_TWD_BASE		0x07020800
 #define SUNXI_R_CPUCFG_BASE		0x07000400
 #define SUNXI_R_I2C_BASE		0x07081400
+#define SUNXI_R_RSB_BASE		0x07083000
 #define SUNXI_R_UART_BASE		0x07080000
 #define SUNXI_R_PIO_BASE		0x07022000
 

plat/allwinner/sun50i_h6/platform.mk

@@ -8,4 +8,4 @@
 include plat/allwinner/common/allwinner-common.mk
 
 BL31_SOURCES		+=	drivers/allwinner/axp/axp805.c		\
-				drivers/mentor/i2c/mi2cv.c
+				drivers/allwinner/sunxi_rsb.c

plat/allwinner/sun50i_h6/sunxi_power.c

@@ -6,20 +6,17 @@
  */
 
 #include <errno.h>
-#include <string.h>
 
-#include <arch_helpers.h>
 #include <common/debug.h>
 #include <drivers/allwinner/axp.h>
-#include <drivers/delay_timer.h>
-#include <drivers/mentor/mi2cv.h>
-#include <lib/mmio.h>
+#include <drivers/allwinner/sunxi_rsb.h>
 
 #include <sunxi_def.h>
 #include <sunxi_mmap.h>
 #include <sunxi_private.h>
 
-#define AXP805_ADDR	0x36
+#define AXP805_HW_ADDR	0x745
+#define AXP805_RT_ADDR	0x3a
 
 static enum pmic_type {
 	UNKNOWN,
@@ -28,67 +25,67 @@ static enum pmic_type {
 
 int axp_read(uint8_t reg)
 {
-	uint8_t val;
-	int ret;
-
-	ret = i2c_write(AXP805_ADDR, 0, 0, &reg, 1);
-	if (ret == 0)
-		ret = i2c_read(AXP805_ADDR, 0, 0, &val, 1);
-	if (ret) {
-		ERROR("PMIC: Cannot read AXP805 register %02x\n", reg);
-		return ret;
-	}
-
-	return val;
+	return rsb_read(AXP805_RT_ADDR, reg);
 }
 
 int axp_write(uint8_t reg, uint8_t val)
 {
-	int ret;
-
-	ret = i2c_write(AXP805_ADDR, reg, 1, &val, 1);
-	if (ret)
-		ERROR("PMIC: Cannot write AXP805 register %02x\n", reg);
-
-	return ret;
+	return rsb_write(AXP805_RT_ADDR, reg, val);
 }
 
-static int axp805_probe(void)
+static int rsb_init(void)
 {
 	int ret;
 
-	/* Switch the AXP805 to master/single-PMIC mode. */
-	ret = axp_write(0xff, 0x0);
+	ret = rsb_init_controller();
 	if (ret)
 		return ret;
 
-	ret = axp_check_id();
+	/* Switch to the recommended 3 MHz bus clock. */
+	ret = rsb_set_bus_speed(SUNXI_OSC24M_CLK_IN_HZ, 3000000);
 	if (ret)
 		return ret;
 
-	return 0;
+	/* Initiate an I2C transaction to switch the PMIC to RSB mode. */
+	ret = rsb_set_device_mode(AXP20X_MODE_RSB << 16 | AXP20X_MODE_REG << 8);
+	if (ret)
+		return ret;
+
+	/* Associate the 8-bit runtime address with the 12-bit bus address. */
+	ret = rsb_assign_runtime_address(AXP805_HW_ADDR, AXP805_RT_ADDR);
+	if (ret)
+		return ret;
+
+	return axp_check_id();
 }
 
 int sunxi_pmic_setup(uint16_t socid, const void *fdt)
 {
 	int ret;
 
-	INFO("PMIC: Probing AXP805 on I2C\n");
+	INFO("PMIC: Probing AXP805 on RSB\n");
 
-	ret = sunxi_init_platform_r_twi(SUNXI_SOC_H6, false);
+	ret = sunxi_init_platform_r_twi(socid, true);
 	if (ret)
 		return ret;
 
-	/* initialise mi2cv driver */
-	i2c_init((void *)SUNXI_R_I2C_BASE);
+	ret = rsb_init();
+	if (ret)
+		return ret;
 
-	ret = axp805_probe();
+	/* Switch the AXP805 to master/single-PMIC mode. */
+	ret = axp_write(0xff, 0x0);
 	if (ret)
 		return ret;
 
 	pmic = AXP805;
 	axp_setup_regulators(fdt);
 
+	/* Switch the PMIC back to I2C mode. */
+	ret = axp_write(AXP20X_MODE_REG, AXP20X_MODE_I2C);
+	if (ret)
+		return ret;
+
 	return 0;
 }
 
@@ -96,10 +93,9 @@ void sunxi_power_down(void)
 {
 	switch (pmic) {
 	case AXP805:
-		/* Re-initialise after rich OS might have used it. */
-		sunxi_init_platform_r_twi(SUNXI_SOC_H6, false);
-		/* initialise mi2cv driver */
-		i2c_init((void *)SUNXI_R_I2C_BASE);
+		/* (Re-)init RSB in case the rich OS has disabled it. */
+		sunxi_init_platform_r_twi(SUNXI_SOC_H6, true);
+		rsb_init();
 		axp_power_off();
 		break;
 	default: