soc/amd/common/block/gpio: add API for gpio override table

This function adds support for gpio_configure_pads_with_override
which:
1. Takes as input two GPIO tables -- base config table and override
config table
2. Configures each pad in base config by first checking if there is a
config available for the pad in override config table. If yes, then
uses the one from override config table. Else, uses the base config to
configure the pad.

BUG=b:153456574
TEST=Build and boot dalboz
BRANCH=none

Signed-off-by: peichao.wang <peichao.wang@bitland.corp-partner.google.com>
Change-Id: I07bfe82827d1f7aea9fcc96574d6deab9e91d503
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/coreboot/+/2153423
Reviewed-by: Furquan Shaikh <furquan@chromium.org>
Commit-Queue: Furquan Shaikh <furquan@chromium.org>
Tested-by: Furquan Shaikh <furquan@chromium.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/41576
Reviewed-by: Furquan Shaikh <furquan@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/soc/amd/common/block/gpio_banks/gpio.c

@@ -294,3 +294,36 @@ int gpio_interrupt_status(gpio_t gpio)
 
 	return 0;
 }
+
+/*
+ * This function checks to see if there is an override config present for the
+ * provided pad_config. If no override config is present, then the input config
+ * is returned. Else, it returns the override config.
+ */
+static const struct soc_amd_gpio *gpio_get_config(const struct soc_amd_gpio *c,
+				const struct soc_amd_gpio *override_cfg_table,
+				size_t num)
+{
+	size_t i;
+	if (override_cfg_table == NULL)
+		return c;
+	for (i = 0; i < num; i++) {
+		if (c->gpio == override_cfg_table[i].gpio)
+			return override_cfg_table + i;
+	}
+	return c;
+}
+void gpio_configure_pads_with_override(const struct soc_amd_gpio *base_cfg,
+					size_t base_num_pads,
+					const struct soc_amd_gpio *override_cfg,
+					size_t override_num_pads)
+{
+	size_t i;
+	const struct soc_amd_gpio *c;
+
+	for (i = 0; i < base_num_pads; i++) {
+		c = gpio_get_config(base_cfg + i, override_cfg,
+				override_num_pads);
+		program_gpios(c, 1);
+	}
+}

src/soc/amd/common/block/include/amdblocks/gpio_banks.h

@@ -276,6 +276,21 @@ enum {
 
 typedef uint32_t gpio_t;
 
+/*
+ * gpio_configure_pads_with_override accepts as input two GPIO tables:
+ * 1. Base config
+ * 2. Override config
+ *
+ * This function configures raw pads in base config and applies override in
+ * override config if any. Thus, for every GPIO_x in base config, this function
+ * looks up the GPIO in override config and if it is present there, then applies
+ * the configuration from override config.
+ */
+void gpio_configure_pads_with_override(const struct soc_amd_gpio *base_cfg,
+					size_t base_num_pads,
+					const struct soc_amd_gpio *override_cfg,
+					size_t override_num_pads);
+
 /* Get the address of the control register of a particular pin */
 uintptr_t gpio_get_address(gpio_t gpio_num);