5 files changed, 77 insertions, 1 deletions
diff --git a/src/drivers/siemens/nc_fpga/Kconfig b/src/drivers/siemens/nc_fpga/Kconfig
index 1cd797772f..f4f1e972ef 100644
--- a/src/drivers/siemens/nc_fpga/Kconfig
+++ b/src/drivers/siemens/nc_fpga/Kconfig
@@ -5,3 +5,8 @@ config DRIVER_SIEMENS_NC_FPGA
 config NC_FPGA_NOTIFY_CB_READY
 	bool
 	default n
+
+config NC_FPGA_POST_CODE
+	bool
+	default n
+	select EARLY_PCI_BRIDGE
diff --git a/src/drivers/siemens/nc_fpga/Makefile.inc b/src/drivers/siemens/nc_fpga/Makefile.inc
index ac2875f52f..95ec00aedc 100644
--- a/src/drivers/siemens/nc_fpga/Makefile.inc
+++ b/src/drivers/siemens/nc_fpga/Makefile.inc
@@ -1,3 +1,9 @@
 ## SPDX-License-Identifier: GPL-2.0-only
 
 ramstage-$(CONFIG_DRIVER_SIEMENS_NC_FPGA) += nc_fpga.c
+
+all-$(CONFIG_NC_FPGA_POST_CODE) += nc_fpga_early.c
+
+ifeq ($(CONFIG_NC_FPGA_POST_CODE),y)
+CPPFLAGS_common += -I$(src)/drivers/siemens/nc_fpga
+endif
diff --git a/src/drivers/siemens/nc_fpga/nc_fpga.c b/src/drivers/siemens/nc_fpga/nc_fpga.c
index 08e88565c1..0b4c7d47ea 100644
--- a/src/drivers/siemens/nc_fpga/nc_fpga.c
+++ b/src/drivers/siemens/nc_fpga/nc_fpga.c
@@ -142,9 +142,21 @@ static void set_fw_done(void *unused)
 BOOT_STATE_INIT_ENTRY(BS_PAYLOAD_BOOT, BS_ON_ENTRY, set_fw_done, NULL);
 #endif
 
+static void nc_fpga_set_resources(struct device *dev)
+{
+	pci_dev_set_resources(dev);
+
+	if (CONFIG(NC_FPGA_POST_CODE)) {
+		/* Re-initialize base address after set_resources for POST display
+		   to work properly.*/
+		nc_fpga_remap(pci_read_config32(dev, PCI_BASE_ADDRESS_0) & ~0xf);
+	}
+}
+
+
 static struct device_operations nc_fpga_ops  = {
 	.read_resources   = pci_dev_read_resources,
-	.set_resources    = pci_dev_set_resources,
+	.set_resources    = nc_fpga_set_resources,
 	.enable_resources = pci_dev_enable_resources,
 	.init             = nc_fpga_init,
 };
diff --git a/src/drivers/siemens/nc_fpga/nc_fpga.h b/src/drivers/siemens/nc_fpga/nc_fpga.h
index 2096de79b7..39cc04e993 100644
--- a/src/drivers/siemens/nc_fpga/nc_fpga.h
+++ b/src/drivers/siemens/nc_fpga/nc_fpga.h
@@ -17,6 +17,7 @@
 #define  NC_DIAG_FW_DONE		0x10000
 #define NC_BL_BRIGHTNESS_OFFSET		0x88
 #define NC_BL_PWM_OFFSET		0x8C
+#define NC_FPGA_POST_OFFSET		0xE0
 #define NC_FANMON_CTRL_OFFSET		0x400
 
 #define MAX_NUM_SENSORS			8
@@ -58,4 +59,7 @@ typedef struct {
 	uint32_t	fanmon;
 } __packed fan_ctrl_t;
 
+void nc_fpga_post(uint8_t value);
+void nc_fpga_remap(uint32_t new_mmio);
+
 #endif /* _SIEMENS_NC_FPGA_H_ */
diff --git a/src/drivers/siemens/nc_fpga/nc_fpga_early.c b/src/drivers/siemens/nc_fpga/nc_fpga_early.c
new file mode 100644
index 0000000000..6ec0349922
--- /dev/null
+++ b/src/drivers/siemens/nc_fpga/nc_fpga_early.c
@@ -0,0 +1,49 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#include <arch/mmio.h>
+#include <device/pci.h>
+#include <device/pci_def.h>
+#include <device/pci_ids.h>
+#include <device/pci_ops.h>
+#include <types.h>
+
+#include "nc_fpga.h"
+
+static DEVTREE_CONST uint32_t fpga_bar = CONFIG_EARLY_PCI_MMIO_BASE;
+static bool nc_fpga_present = false;
+
+int pci_early_device_probe(u8 bus, u8 dev, u32 mmio_base)
+{
+	pci_devfn_t pci_dev = PCI_DEV(bus, dev, 0);
+	uint32_t id = pci_s_read_config32(pci_dev, PCI_VENDOR_ID);
+
+	if (id != (0x4091 << 16 | PCI_VENDOR_ID_SIEMENS))
+		return -1;
+
+	/* Setup base address for BAR0. */
+	pci_s_write_config32(pci_dev, PCI_BASE_ADDRESS_0, mmio_base);
+	/* Enable memory access for pci_dev. */
+	u16 reg16 = pci_s_read_config16(pci_dev, PCI_COMMAND);
+	reg16 |= PCI_COMMAND_MEMORY;
+	pci_s_write_config16(pci_dev, PCI_COMMAND, reg16);
+	nc_fpga_present = true;
+
+	return 0;
+}
+
+void nc_fpga_remap(uint32_t new_mmio)
+{
+#if ENV_RAMSTAGE
+	fpga_bar = new_mmio;
+#endif
+}
+
+void nc_fpga_post(uint8_t value)
+{
+	/* The function pci_earyl_device_probe is called in bootblock and romstage. Make sure
+	   that in these stages the initialization code was successful before the POST code
+	   value is written to the register. */
+	if ((ENV_BOOTBLOCK || ENV_ROMSTAGE) && nc_fpga_present == false)
+		return;
+	write32((void *)(fpga_bar + NC_FPGA_POST_OFFSET), value);
+}