dedede: Change PP3300_A PGOOD update method

We cannot read the ADCs in interrupt context, therefore we are changing
the method in which we determine the PP3300_A_PGOOD status.  This commit
adds a ADC threshold interrupt for the PP3300_A PGOOD signal which
updates a variable in SRAM.  This way, the chipset task can simply use
that variable for the PGOOD status instead of performing an ADC
conversion in interrupt context.

BUG=b:148169171
BRANCH=None
TEST=Build and flash waddledoo, verify that PP3300_A PGOOD is updated
correctly.
TEST=Verify that DUT does not panic while power sequencing

Change-Id: Ia88e0d1d95ea97c41dc4094997c0633ca1027cac
Signed-off-by: Aseda Aboagye <aaboagye@google.com>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/2030205
Tested-by: Aseda Aboagye <aaboagye@chromium.org>
Commit-Queue: Aseda Aboagye <aaboagye@chromium.org>
Reviewed-by: Diana Z <dzigterman@chromium.org>

1 files changed, 65 insertions, 0 deletions

diff --git a/baseboard/dedede/variant_ec_npcx796fc.c b/baseboard/dedede/variant_ec_npcx796fc.c
index d981b2e786..4ef55cf682 100644
--- a/baseboard/dedede/variant_ec_npcx796fc.c
+++ b/baseboard/dedede/variant_ec_npcx796fc.c
@@ -6,13 +6,18 @@
 /* Common code for VARIANT_DEDEDE_NPCX796FC configuration */
 
 #include "adc_chip.h"
+#include "atomic.h"
 #include "common.h"
 #include "compile_time_macros.h"
+#include "console.h"
 #include "gpio.h"
+#include "hooks.h"
 #include "i2c.h"
+#include "power.h"
 #include "pwm.h"
 #include "pwm_chip.h"
 #include "registers.h"
+#include "task.h"
 
 /* ADC channels */
 const struct adc_t adc_channels[] = {
@@ -31,6 +36,66 @@ const struct adc_t adc_channels[] = {
 };
 BUILD_ASSERT(ARRAY_SIZE(adc_channels) == ADC_CH_COUNT);
 
+void pp3300_a_pgood_high(void)
+{
+	atomic_or(&pp3300_a_pgood, 1);
+
+	/* Disable this interrupt while it's asserted. */
+	npcx_adc_thresh_int_enable(NPCX_ADC_THRESH1, 0);
+	/* Enable the voltage low interrupt. */
+	npcx_adc_thresh_int_enable(NPCX_ADC_THRESH2, 1);
+
+	/*
+	 * Call power_signal_interrupt() with a dummy GPIO in order for the
+	 * chipset task to pick up the change in power sequencing signals.
+	 */
+	power_signal_interrupt(GPIO_PG_EC_DSW_PWROK);
+}
+
+void pp3300_a_pgood_low(void)
+{
+	atomic_clear(&pp3300_a_pgood, 1);
+
+	/* Disable this interrupt while it's asserted. */
+	npcx_adc_thresh_int_enable(NPCX_ADC_THRESH2, 0);
+	/* Enable the voltage high interrupt. */
+	npcx_adc_thresh_int_enable(NPCX_ADC_THRESH1, 1);
+
+	/*
+	 * Call power_signal_interrupt() with a dummy GPIO in order for the
+	 * chipset task to pick up the change in power sequencing signals.
+	 */
+	power_signal_interrupt(GPIO_PG_EC_DSW_PWROK);
+}
+
+const struct npcx_adc_thresh_t adc_pp3300_a_pgood_high = {
+	.adc_ch = ADC_VSNS_PP3300_A,
+	.adc_thresh_cb = pp3300_a_pgood_high,
+	.thresh_assert = 2700,
+	.thresh_deassert = -1,
+};
+
+const struct npcx_adc_thresh_t adc_pp3300_a_pgood_low = {
+	.adc_ch = ADC_VSNS_PP3300_A,
+	.adc_thresh_cb = pp3300_a_pgood_low,
+	.lower_or_higher = 1,
+	.thresh_assert = 600,
+	.thresh_deassert = -1,
+};
+
+static void set_up_adc_irqs(void)
+{
+	/* Set interrupt thresholds for the ADC. */
+	npcx_adc_register_thresh_irq(NPCX_ADC_THRESH1,
+				     &adc_pp3300_a_pgood_high);
+	npcx_adc_register_thresh_irq(NPCX_ADC_THRESH2, &adc_pp3300_a_pgood_low);
+	npcx_set_adc_repetitive(adc_channels[ADC_VSNS_PP3300_A].input_ch, 1);
+	npcx_adc_thresh_int_enable(NPCX_ADC_THRESH1, 1);
+	npcx_adc_thresh_int_enable(NPCX_ADC_THRESH2, 1);
+}
+DECLARE_HOOK(HOOK_INIT, set_up_adc_irqs, HOOK_PRIO_INIT_ADC+1);
+
+
 /* I2C Ports */
 const struct i2c_port_t i2c_ports[] = {
 	{