soc/amd/common/gpio: Make macro names for GPIO flags consistent

`soc_amd_gpio` structure uses a flag field to store additional
information about GPIO configuration that does not end up directly in
the GPIO control register. However, the naming for these flags is not
consistent across event triggers and special configurations. This
change updates the flag names to be consistent (starting with
GPIO_FLAG_*) and adds some helper functions for GPIO events.

In the following CLs, more changes will be made to drop some of the
special flags which are not really required.

BUG=b:159944426

Change-Id: Idca795c3e594eb956d297d5ba5d08f75b5563ee5
Signed-off-by: Furquan Shaikh <furquan@google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/42869
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-by: Raul Rangel <rrangel@chromium.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

2 files changed, 73 insertions, 48 deletions

diff --git a/src/soc/amd/common/block/gpio_banks/gpio.c b/src/soc/amd/common/block/gpio_banks/gpio.c
index 4d6d164498..d7ac89667b 100644
--- a/src/soc/amd/common/block/gpio_banks/gpio.c
+++ b/src/soc/amd/common/block/gpio_banks/gpio.c
@@ -32,21 +32,22 @@ static void mem_read_write32(uint32_t *address, uint32_t value, uint32_t mask)
 	write32(address, reg32);
 }
 
-static void program_smi(uint32_t trigger, int gevent_num)
+static void program_smi(uint32_t flags, int gevent_num)
 {
-	/*
-	 * Only level trigger is allowed for SMI. Trigger values are 0
-	 * through 3, with 0-1 being level trigger and 2-3 being edge
-	 * trigger. GPIO_TRIGGER_EDGE_LOW is 2, so trigger has to be
-	 * less than GPIO_TRIGGER_EDGE_LOW.
-	 */
-	assert(trigger < GPIO_TRIGGER_EDGE_LOW);
+	uint8_t level;
 
-	if (trigger == GPIO_TRIGGER_LEVEL_HIGH)
-		configure_gevent_smi(gevent_num, SMI_MODE_SMI, SMI_SCI_LVL_HIGH);
+	if (!is_gpio_event_level_triggered(flags)) {
+		printk(BIOS_ERR, "ERROR: %s - Only level trigger allowed for SMI!\n", __func__);
+		assert(0);
+		return;
+	}
+
+	if (is_gpio_event_active_high(flags))
+		level = SMI_SCI_LVL_HIGH;
+	else
+		level = SMI_SCI_LVL_LOW;
 
-	if (trigger == GPIO_TRIGGER_LEVEL_LOW)
-		configure_gevent_smi(gevent_num, SMI_MODE_SMI, SMI_SCI_LVL_LOW);
+	configure_gevent_smi(gevent_num, SMI_MODE_SMI, level);
 }
 
 struct sci_trigger_regs {
@@ -62,20 +63,18 @@ struct sci_trigger_regs {
  * In a similar fashion, polarity (rising/falling, hi/lo) of each GPE is
  * represented as a single bit in SMI_SCI_TRIG register.
  */
-static void fill_sci_trigger(uint32_t trigger, int gpe, struct sci_trigger_regs *regs)
+static void fill_sci_trigger(uint32_t flags, int gpe, struct sci_trigger_regs *regs)
 {
 	uint32_t mask = 1 << gpe;
 
 	regs->mask |= mask;
 
-	/* Select level vs. edge triggered event. */
-	if ((trigger == GPIO_TRIGGER_LEVEL_LOW) || (trigger == GPIO_TRIGGER_LEVEL_HIGH))
+	if (is_gpio_event_level_triggered(flags))
 		regs->level |= mask;
 	else
 		regs->level &= ~mask;
 
-	/* Select rising/high vs falling/low trigger. */
-	if ((trigger == GPIO_TRIGGER_EDGE_HIGH) || (trigger == GPIO_TRIGGER_LEVEL_HIGH))
+	if (is_gpio_event_active_high(flags))
 		regs->polarity |= mask;
 	else
 		regs->polarity &= ~mask;
@@ -217,38 +216,37 @@ void program_gpios(const struct soc_amd_gpio *gpio_list_ptr, size_t size)
 
 		gpio_ptr = gpio_ctrl_ptr(gpio);
 
-		if (control_flags & GPIO_SPECIAL_FLAG) {
+		if (control_flags & GPIO_FLAG_SPECIAL_MASK) {
 			gevent_num = get_gpio_gevent(gpio, gev_tbl, gev_items);
 			if (gevent_num < 0) {
 				printk(BIOS_WARNING, "Warning: GPIO pin %d has"
 					" no associated gevent!\n", gpio);
 				continue;
 			}
-			switch (control_flags & GPIO_SPECIAL_MASK) {
-			case GPIO_DEBOUNCE_FLAG:
+			switch (control_flags & GPIO_FLAG_SPECIAL_MASK) {
+			case GPIO_FLAG_DEBOUNCE:
 				mem_read_write32(gpio_ptr, control,
 						GPIO_DEBOUNCE_MASK);
 				break;
-			case GPIO_WAKE_FLAG:
+			case GPIO_FLAG_WAKE:
 				mem_read_write32(gpio_ptr, control,
 						INT_WAKE_MASK);
 				break;
-			case GPIO_INT_FLAG:
+			case GPIO_FLAG_INT:
 				mem_read_write32(gpio_ptr, control,
 						AMD_GPIO_CONTROL_MASK);
 				break;
-			case GPIO_SMI_FLAG:
+			case GPIO_FLAG_SMI:
 				mem_read_write32(gpio_ptr, control,
 						INT_SCI_SMI_MASK);
 
-				program_smi(control_flags & FLAGS_TRIGGER_MASK, gevent_num);
+				program_smi(control_flags, gevent_num);
 				break;
-			case GPIO_SCI_FLAG:
+			case GPIO_FLAG_SCI:
 				mem_read_write32(gpio_ptr, control,
 						INT_SCI_SMI_MASK);
 
-				fill_sci_trigger(control_flags & FLAGS_TRIGGER_MASK, gevent_num,
-						 &sci_trigger_cfg);
+				fill_sci_trigger(control_flags, gevent_num, &sci_trigger_cfg);
 
 				soc_route_sci(gevent_num);
 				break;
diff --git a/src/soc/amd/common/block/include/amdblocks/gpio_banks.h b/src/soc/amd/common/block/include/amdblocks/gpio_banks.h
index 92aa8a2e4f..0521e4c520 100644
--- a/src/soc/amd/common/block/include/amdblocks/gpio_banks.h
+++ b/src/soc/amd/common/block/include/amdblocks/gpio_banks.h
@@ -4,6 +4,7 @@
 #define __AMDBLOCK_GPIO_BANKS_H__
 
 #include <stdint.h>
+#include <stdbool.h>
 #include <stddef.h>
 
 struct soc_amd_gpio {
@@ -106,27 +107,53 @@ enum {
 #define GPIO_INT_LEVEL_HIGH		(GPIO_ACTIVE_HIGH | GPIO_LEVEL_TRIG)
 #define GPIO_INT_LEVEL_LOW		(GPIO_ACTIVE_LOW | GPIO_LEVEL_TRIG)
 
-enum {
-	GPIO_TRIGGER_LEVEL_LOW,
-	GPIO_TRIGGER_LEVEL_HIGH,
-	GPIO_TRIGGER_EDGE_LOW,
-	GPIO_TRIGGER_EDGE_HIGH,
-};
+/*
+ * Flags used for GPIO configuration. These provide additional information that does not go
+ * directly into GPIO control register. These are stored in `flags` field in soc_amd_gpio.
+ */
+#define GPIO_FLAG_EVENT_TRIGGER_LEVEL	(1 << 0)
+#define GPIO_FLAG_EVENT_TRIGGER_EDGE	(0 << 0)
+#define GPIO_FLAG_EVENT_TRIGGER_MASK	(1 << 0)
+#define GPIO_FLAG_EVENT_ACTIVE_HIGH	(1 << 1)
+#define GPIO_FLAG_EVENT_ACTIVE_LOW	(0 << 1)
+#define GPIO_FLAG_EVENT_ACTIVE_MASK	(1 << 1)
+#define GPIO_FLAG_SCI			(1 << 2)
+#define GPIO_FLAG_SMI			(1 << 3)
+#define GPIO_FLAG_DEBOUNCE		(1 << 4)
+#define GPIO_FLAG_WAKE			(1 << 5)
+#define GPIO_FLAG_INT			(1 << 6)
+#define GPIO_FLAG_SPECIAL_MASK	        (0x1f << 2)
+
+/* Trigger configuration for GPIO SCI/SMI events. */
+#define GPIO_FLAG_EVENT_TRIGGER_LEVEL_HIGH	(GPIO_FLAG_EVENT_TRIGGER_LEVEL | \
+						 GPIO_FLAG_EVENT_ACTIVE_HIGH)
+#define GPIO_FLAG_EVENT_TRIGGER_LEVEL_LOW	(GPIO_FLAG_EVENT_TRIGGER_LEVEL | \
+						 GPIO_FLAG_EVENT_ACTIVE_LOW)
+#define GPIO_FLAG_EVENT_TRIGGER_EDGE_HIGH	(GPIO_FLAG_EVENT_TRIGGER_EDGE | \
+						 GPIO_FLAG_EVENT_ACTIVE_HIGH)
+#define GPIO_FLAG_EVENT_TRIGGER_EDGE_LOW	(GPIO_FLAG_EVENT_TRIGGER_EDGE | \
+						 GPIO_FLAG_EVENT_ACTIVE_LOW)
+
+static inline bool is_gpio_event_level_triggered(uint32_t flags)
+{
+	return (flags & GPIO_FLAG_EVENT_TRIGGER_MASK) == GPIO_FLAG_EVENT_TRIGGER_LEVEL;
+}
+
+static inline bool is_gpio_event_edge_triggered(uint32_t flags)
+{
+	return (flags & GPIO_FLAG_EVENT_TRIGGER_MASK) == GPIO_FLAG_EVENT_TRIGGER_EDGE;
+}
+
+static inline bool is_gpio_event_active_high(uint32_t flags)
+{
+	return (flags & GPIO_FLAG_EVENT_ACTIVE_MASK) == GPIO_FLAG_EVENT_ACTIVE_HIGH;
+}
+
+static inline bool is_gpio_event_active_low(uint32_t flags)
+{
+	return (flags & GPIO_FLAG_EVENT_ACTIVE_MASK) == GPIO_FLAG_EVENT_ACTIVE_LOW;
+}
 
-#define GPIO_SPECIAL_FLAG		(1 << 31)
-#define GPIO_DEBOUNCE_FLAG		(1 << 30)
-#define GPIO_WAKE_FLAG			(1 << 29)
-#define GPIO_INT_FLAG			(1 << 28)
-#define GPIO_SMI_FLAG			(1 << 27)
-#define GPIO_SCI_FLAG			(1 << 26)
-#define GPIO_FLAG_DEBOUNCE		(GPIO_SPECIAL_FLAG | GPIO_DEBOUNCE_FLAG)
-#define GPIO_FLAG_WAKE			(GPIO_SPECIAL_FLAG | GPIO_WAKE_FLAG)
-#define GPIO_FLAG_INT			(GPIO_SPECIAL_FLAG | GPIO_INT_FLAG)
-#define GPIO_FLAG_SCI			(GPIO_SPECIAL_FLAG | GPIO_SCI_FLAG)
-#define GPIO_FLAG_SMI			(GPIO_SPECIAL_FLAG | GPIO_SMI_FLAG)
-
-#define FLAGS_TRIGGER_MASK		0x00000003
-#define GPIO_SPECIAL_MASK		0x7c000000
 #define GPIO_DEBOUNCE_MASK		0x000000ff
 #define INT_TRIGGER_MASK		0x00000700
 #define INT_WAKE_MASK			0x0000e700
@@ -238,7 +265,7 @@ enum {
 			    GPIO_EVENT_INT ## _ ## action), \
 		.flags = GPIO_FLAG_INT }
 /* Auxiliary macro for SCI and SMI */
-#define PAD_AUX2(trigger, flag) (GPIO_TRIGGER ## _ ## trigger | flag)
+#define PAD_AUX2(trigger, flag) (GPIO_FLAG_EVENT_TRIGGER ## _ ## trigger | flag)
 /* SCI pad configuration */
 #define PAD_SCI(pin, pull, trigger) \
 	{ .gpio = (pin), \