soc/amd/picasso/data_fabric: move more helper functions to common code

The number of data fabric MMIO registers is SoC-specific, so we need to
keep that in the SoC code. This also removes a redundant pair of
brackets and moves a loop counter declaration into the head of the loop.

Signed-off-by: Felix Held <felix-coreboot@felixheld.de>
Change-Id: I8499f1c1f7bf6849b5955a463de2e06962d5de68
Reviewed-on: https://review.coreboot.org/c/coreboot/+/50638
Reviewed-by: Marshall Dawson <marshalldawson3rd@gmail.com>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

1 files changed, 24 insertions, 0 deletions

diff --git a/src/soc/amd/common/block/data_fabric/data_fabric_helper.c b/src/soc/amd/common/block/data_fabric/data_fabric_helper.c
index e784d508ff..d65bc8dac6 100644
--- a/src/soc/amd/common/block/data_fabric/data_fabric_helper.c
+++ b/src/soc/amd/common/block/data_fabric/data_fabric_helper.c
@@ -3,6 +3,7 @@
 #include <amdblocks/data_fabric.h>
 #include <amdblocks/pci_devs.h>
 #include <device/pci_ops.h>
+#include <soc/data_fabric.h>
 #include <soc/pci_devs.h>
 #include <types.h>
 #include "data_fabric_def.h"
@@ -40,3 +41,26 @@ void data_fabric_write32(uint8_t function, uint16_t reg, uint8_t instance_id, ui
 	data_fabric_set_indirect_address(function, reg, instance_id);
 	pci_write_config32(SOC_DF_F4_DEV, DF_FICAD_LO, data);
 }
+
+void data_fabric_disable_mmio_reg(unsigned int reg)
+{
+	data_fabric_broadcast_write32(0, NB_MMIO_CONTROL(reg),
+		IOMS0_FABRIC_ID << MMIO_DST_FABRIC_ID_SHIFT);
+	data_fabric_broadcast_write32(0, NB_MMIO_BASE(reg), 0);
+	data_fabric_broadcast_write32(0, NB_MMIO_LIMIT(reg), 0);
+}
+
+static bool is_mmio_reg_disabled(unsigned int reg)
+{
+	uint32_t val = data_fabric_broadcast_read32(0, NB_MMIO_CONTROL(reg));
+	return !(val & (MMIO_WE | MMIO_RE));
+}
+
+int data_fabric_find_unused_mmio_reg(void)
+{
+	for (unsigned int i = 0; i < NUM_NB_MMIO_REGS; i++) {
+		if (is_mmio_reg_disabled(i))
+			return i;
+	}
+	return -1;
+}