drivers/ipmi: add code to set BMC/IPMI enablement from jumper

Some boards, like the Supermicro X11SSM-F, have a jumper for enabling or
disabling the BMC and IPMI. Add a new devicetree driver option to set
the GPIO used for the jumper and enable or disable IPMI according to its
value.

This gets used in a follow-up change by Supermicro X11SSM-F.

Test: Boot with jumper set to each enabled and disabled and check debug
log if IPMI gets enabled/disabled accordingly.

Successfully tested on Supermicro X11SSM-F with CB:48095.

Signed-off-by: Michael Niewöhner <foss@mniewoehner.de>
Tested-by: Michael Niewöhner <foss@mniewoehner.de>
Change-Id: Icde3232843a7138797a4b106560f170972edeb9c
Reviewed-on: https://review.coreboot.org/c/coreboot/+/48094
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Tim Wawrzynczak <twawrzynczak@chromium.org>

2 files changed, 30 insertions, 5 deletions

diff --git a/src/drivers/ipmi/chip.h b/src/drivers/ipmi/chip.h
index f561bcd893..11bef9b02f 100644
--- a/src/drivers/ipmi/chip.h
+++ b/src/drivers/ipmi/chip.h
@@ -1,8 +1,12 @@
 /* SPDX-License-Identifier: GPL-2.0-only */
 
+#include <device/device.h>
+
 #ifndef _IMPI_CHIP_H_
 #define _IPMI_CHIP_H_
 
+#include <stdint.h>
+
 struct drivers_ipmi_config {
 	u8 bmc_i2c_address;
 	u8 have_nv_storage;
@@ -11,6 +15,13 @@ struct drivers_ipmi_config {
 	u8 gpe_interrupt;
 	u8 have_apic;
 	u32 apic_interrupt;
+	/* Device to use for GPIO operations */
+	DEVTREE_CONST struct device *gpio_dev;
+	/*
+	 * Jumper GPIO for enabling / disabling BMC/IPMI
+	 * If present, the jumper overrides the devicetree.
+	 */
+	u32 bmc_jumper_gpio;
 	/*
 	 * Wait for BMC to boot.
 	 * This can be used if the BMC takes a long time to boot after PoR:
diff --git a/src/drivers/ipmi/ipmi_kcs_ops.c b/src/drivers/ipmi/ipmi_kcs_ops.c
index 38311ee7eb..f261934c96 100644
--- a/src/drivers/ipmi/ipmi_kcs_ops.c
+++ b/src/drivers/ipmi/ipmi_kcs_ops.c
@@ -11,6 +11,7 @@
 #include <arch/io.h>
 #include <console/console.h>
 #include <device/device.h>
+#include <device/gpio.h>
 #include <device/pnp.h>
 #if CONFIG(HAVE_ACPI_TABLES)
 #include <acpi/acpi.h>
@@ -78,19 +79,32 @@ static void ipmi_kcs_init(struct device *dev)
 	struct ipmi_devid_rsp rsp;
 	uint32_t man_id = 0, prod_id = 0;
 	struct drivers_ipmi_config *conf = dev->chip_info;
+	const struct gpio_operations *gpio_ops;
 	struct ipmi_selftest_rsp selftestrsp = {0};
 	uint8_t retry_count;
 
-	if (!dev->enabled)
-		return;
-
-	printk(BIOS_DEBUG, "IPMI: PNP KCS 0x%x\n", dev->path.pnp.port);
-
 	if (!conf) {
 		printk(BIOS_WARNING, "IPMI: chip_info is missing! Skip init.\n");
 		return;
 	}
 
+	if (conf->bmc_jumper_gpio) {
+		gpio_ops = dev_get_gpio_ops(conf->gpio_dev);
+		if (!gpio_ops) {
+			printk(BIOS_WARNING, "IPMI: gpio device is missing gpio ops!\n");
+		} else {
+			/* Get jumper value and set device state accordingly */
+			dev->enabled = gpio_ops->get(conf->bmc_jumper_gpio);
+			if (!dev->enabled)
+				printk(BIOS_INFO, "IPMI: Disabled by jumper\n");
+		}
+	}
+
+	if (!dev->enabled)
+		return;
+
+	printk(BIOS_DEBUG, "IPMI: PNP KCS 0x%x\n", dev->path.pnp.port);
+
 	/* Get IPMI version for ACPI and SMBIOS */
 	if (conf->wait_for_bmc && conf->bmc_boot_timeout) {
 		struct stopwatch sw;