soc/amd/common/espi,mb/: Allow configuring open drain ALERT#
Some designs might wish to use an open drain eSPI ALERT#. This change
adds an enum that allows setting the eSPI alert mode.
BUG=b:187122344, b:186135022
TEST=Boot guybrush using all 3 alert modes
Signed-off-by: Raul E Rangel <rrangel@chromium.org>
Change-Id: Ia35fc59a699cf9444b53aad5c9bb71aa27ce9251
Reviewed-on: https://review.coreboot.org/c/coreboot/+/52954
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Karthik Ramasubramanian <kramasub@google.com>
Reviewed-by: Furquan Shaikh <furquan@google.com>
diff --git a/src/soc/amd/common/block/lpc/espi_util.c b/src/soc/amd/common/block/lpc/espi_util.c
index 519130a6..81056b0 100644
--- a/src/soc/amd/common/block/lpc/espi_util.c
+++ b/src/soc/amd/common/block/lpc/espi_util.c
@@ -683,6 +683,29 @@
}
}
+static void espi_set_alert_pin_config(enum espi_alert_pin alert_pin, uint32_t slave_caps,
+ uint32_t *slave_config, uint32_t *ctrlr_config)
+{
+ switch (alert_pin) {
+ case ESPI_ALERT_PIN_IN_BAND:
+ *slave_config |= ESPI_SLAVE_ALERT_MODE_IO1;
+ return;
+ case ESPI_ALERT_PIN_PUSH_PULL:
+ *slave_config |= ESPI_SLAVE_ALERT_MODE_PIN | ESPI_SLAVE_PUSH_PULL_ALERT_SEL;
+ *ctrlr_config |= ESPI_ALERT_MODE;
+ return;
+ case ESPI_ALERT_PIN_OPEN_DRAIN:
+ if (!(slave_caps & ESPI_SLAVE_OPEN_DRAIN_ALERT_SUPP))
+ die("eSPI peripheral does not support open drain alert!");
+
+ *slave_config |= ESPI_SLAVE_ALERT_MODE_PIN | ESPI_SLAVE_OPEN_DRAIN_ALERT_SEL;
+ *ctrlr_config |= ESPI_ALERT_MODE;
+ return;
+ default:
+ die("Unknown espi alert config: %u!\n", alert_pin);
+ }
+}
+
static int espi_set_general_configuration(const struct espi_config *mb_cfg, uint32_t slave_caps)
{
uint32_t slave_config = 0;
@@ -693,11 +716,7 @@
ctrlr_config |= ESPI_CRC_CHECKING_EN;
}
- if (mb_cfg->dedicated_alert_pin) {
- slave_config |= ESPI_SLAVE_ALERT_MODE_PIN;
- ctrlr_config |= ESPI_ALERT_MODE;
- }
-
+ espi_set_alert_pin_config(mb_cfg->alert_pin, slave_caps, &slave_config, &ctrlr_config);
espi_set_io_mode_config(mb_cfg->io_mode, slave_caps, &slave_config, &ctrlr_config);
espi_set_op_freq_config(mb_cfg->op_freq_mhz, slave_caps, &slave_config, &ctrlr_config);