mb/siemens/mc_ehl2: Use preset driver strength for SD-Card
The intention of predefining driver strength is to avoid that the OS
SD-Card driver changes this setting.
Change-Id: I02fdac94462da1cd77f8dc972faf16f28d94c946
Signed-off-by: Mario Scheithauer <mario.scheithauer@siemens.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/68166
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Werner Zeh <werner.zeh@siemens.com>
diff --git a/src/mainboard/siemens/mc_ehl/variants/mc_ehl2/mainboard.c b/src/mainboard/siemens/mc_ehl/variants/mc_ehl2/mainboard.c
index a798398..3395160 100644
--- a/src/mainboard/siemens/mc_ehl/variants/mc_ehl2/mainboard.c
+++ b/src/mainboard/siemens/mc_ehl/variants/mc_ehl2/mainboard.c
@@ -9,6 +9,8 @@
#include <soc/pci_devs.h>
#include <soc/pcr_ids.h>
+#define HOSTCTRL2 0x3E
+#define HOSTCTRL2_PRESET (1 << 15)
#define SD_CAP_BYP 0x810
#define SD_CAP_BYP_EN 0x5A
#define SD_CAP_BYP_REG1 0x814
@@ -34,6 +36,7 @@
dev = pcidev_path_on_root(PCH_DEVFN_SDCARD);
if (dev) {
uint32_t reg;
+ uint16_t reg16;
struct resource *res = probe_resource(dev, PCI_BASE_ADDRESS_0);
if (!res)
return;
@@ -43,6 +46,11 @@
reg &= ~(SD_CAP_BYP_SDR104 | SD_CAP_BYP_SDR50);
reg |= SD_CAP_BYP_DDR50;
write32(res2mmio(res, SD_CAP_BYP_REG1, 0), reg);
+
+ /* Use preset driver strength from preset value registers. */
+ reg16 = read16(res2mmio(res, HOSTCTRL2, 0));
+ reg16 |= HOSTCTRL2_PRESET;
+ write16(res2mmio(res, HOSTCTRL2, 0), reg16);
}
}