soc/amd/common: Introduce I2C driver common to all AMD SoCs

I2C driver is replicated in each generation of AMD SoCs. Introduce a
common I2C driver that can be used across all the AMD SoCs. To begin
with, peripheral reset functionality is moved into this common driver.
SoC specific I2C driver passes the SCL pin configuration in order for
the common driver to reset the peripherals. More functionality can be
moved here in subsequent changes.

Also sb_reset_i2c_slaves() is renamed as sb_reset_i2c_peripherals() as
an effort towards using inclusive language.

BUG=None
TEST=Build Dalboz and Grunt. Boot to OS in Dalboz. Ensure that the I2C
peripherals are detected as earlier in Dalboz.
localhost ~ # i2cdetect -y 0
Warning: Can't use SMBus Quick Write command, will skip some addresses
     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
00:
10:
20:
30: -- -- -- -- -- -- -- --
40:
50: 50 51 -- -- -- -- -- -- 58 59 -- -- -- -- -- --
60:
70:
localhost ~ # i2cdetect -y 1
Warning: Can't use SMBus Quick Write command, will skip some addresses
     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
00:
10:
20:
30: -- -- -- -- -- -- -- --
40:
50: UU -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
60:
70:

Change-Id: I9f735dcfe8375abdc88ff06e8c4f8a6b741bc085
Signed-off-by: Karthikeyan Ramasubramanian <kramasub@google.com>
Suggested-by: Kyosti Malkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/51404
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Mathew King <mathewk@chromium.org>
Reviewed-by: Furquan Shaikh <furquan@google.com>

1 files changed, 36 insertions, 0 deletions

diff --git a/src/soc/amd/common/block/include/amdblocks/i2c.h b/src/soc/amd/common/block/include/amdblocks/i2c.h
new file mode 100644
index 0000000000..9fa203bf57
--- /dev/null
+++ b/src/soc/amd/common/block/include/amdblocks/i2c.h
@@ -0,0 +1,36 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#ifndef AMD_COMMON_BLOCK_I2C_H
+#define AMD_COMMON_BLOCK_I2C_H
+
+#include <amdblocks/gpio_banks.h>
+#include <types.h>
+
+/**
+ * Data structure to identify GPIO to be toggled to reset peripherals on an I2C bus.
+ * @pin:	GPIO corresponding to I2C SCL that needs to be toggled/bit-banged.
+ * @pin_mask:	Bit Mask of a single I2C bus that needs to be reset.
+ */
+struct soc_i2c_scl_pin {
+	struct soc_amd_gpio pin;
+	uint8_t pin_mask;
+};
+
+/**
+ * Information about I2C peripherals that need to be reset.
+ * @i2c_scl_reset_mask:	Bit mask of I2C buses that need to be reset based on the device tree
+ *			configuration.
+ * @i2c_scl:		SoC specific I2C SCL pins that need to be bit-banged as part of reset
+ *			procedure.
+ * @num_pins:		Number of pins defined in @i2c_scl.
+ */
+struct soc_i2c_peripheral_reset_info {
+	uint8_t i2c_scl_reset_mask;
+	const struct soc_i2c_scl_pin *i2c_scl;
+	uint32_t num_pins;
+};
+
+/* Reset I2C peripherals. */
+void sb_reset_i2c_peripherals(const struct soc_i2c_peripheral_reset_info *reset_info);
+
+#endif /* AMD_COMMON_BLOCK_I2C_H */