[PATCH v4 3/5] i2c: piix4: Move SB800_PIIX4_FCH_PM_ADDR definition to amd/fch.h

From: Mario Limonciello
Date: Mon Apr 14 2025 - 20:28:06 EST


From: Mario Limonciello <mario.limonciello@xxxxxxx>

SB800_PIIX4_FCH_PM_ADDR is used to indicate the base address for the
FCH PM registers. Multiple drivers may need this base address, so
move it to a common header location and rename accordingly.

Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx>
---
v4:
* Move FCH_PM_DECODEEN to fch.h, but shift it for use in piix4 because
piix4 does 8 bit reads
---
arch/x86/include/asm/amd/fch.h | 12 ++++++++++++
drivers/i2c/busses/i2c-piix4.c | 18 +++++++++---------
2 files changed, 21 insertions(+), 9 deletions(-)
create mode 100644 arch/x86/include/asm/amd/fch.h

diff --git a/arch/x86/include/asm/amd/fch.h b/arch/x86/include/asm/amd/fch.h
new file mode 100644
index 0000000000000..a5fd91ff92df3
--- /dev/null
+++ b/arch/x86/include/asm/amd/fch.h
@@ -0,0 +1,12 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef _ASM_X86_AMD_FCH_H_
+#define _ASM_X86_AMD_FCH_H_
+
+#define FCH_PM_BASE 0xFED80300
+
+/* register offsets from PM base */
+#define FCH_PM_DECODEEN 0x00
+#define FCH_PM_DECODEEN_SMBUS0SEL GENMASK(20, 19)
+
+#endif
diff --git a/drivers/i2c/busses/i2c-piix4.c b/drivers/i2c/busses/i2c-piix4.c
index dd75916157f05..6350003de32b1 100644
--- a/drivers/i2c/busses/i2c-piix4.c
+++ b/drivers/i2c/busses/i2c-piix4.c
@@ -21,6 +21,7 @@
an i2c_algorithm to access them.
*/

+#include <asm/amd/fch.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/pci.h>
@@ -80,12 +81,11 @@
#define SB800_PIIX4_PORT_IDX_MASK 0x06
#define SB800_PIIX4_PORT_IDX_SHIFT 1

-/* On kerncz and Hudson2, SmBus0Sel is at bit 20:19 of PMx00 DecodeEn */
-#define SB800_PIIX4_PORT_IDX_KERNCZ 0x02
-#define SB800_PIIX4_PORT_IDX_MASK_KERNCZ 0x18
+/* SmBus0Sel is at bit 20:19 of PMx00 DecodeEn */
+#define SB800_PIIX4_PORT_IDX_KERNCZ (FCH_PM_DECODEEN + 0x02)
+#define SB800_PIIX4_PORT_IDX_MASK_KERNCZ (FCH_PM_DECODEEN_SMBUS0SEL >> 16)
#define SB800_PIIX4_PORT_IDX_SHIFT_KERNCZ 3

-#define SB800_PIIX4_FCH_PM_ADDR 0xFED80300
#define SB800_PIIX4_FCH_PM_SIZE 8
#define SB800_ASF_ACPI_PATH "\\_SB.ASFC"

@@ -162,19 +162,19 @@ int piix4_sb800_region_request(struct device *dev, struct sb800_mmio_cfg *mmio_c
if (mmio_cfg->use_mmio) {
void __iomem *addr;

- if (!request_mem_region_muxed(SB800_PIIX4_FCH_PM_ADDR,
+ if (!request_mem_region_muxed(FCH_PM_BASE,
SB800_PIIX4_FCH_PM_SIZE,
"sb800_piix4_smb")) {
dev_err(dev,
"SMBus base address memory region 0x%x already in use.\n",
- SB800_PIIX4_FCH_PM_ADDR);
+ FCH_PM_BASE);
return -EBUSY;
}

- addr = ioremap(SB800_PIIX4_FCH_PM_ADDR,
+ addr = ioremap(FCH_PM_BASE,
SB800_PIIX4_FCH_PM_SIZE);
if (!addr) {
- release_mem_region(SB800_PIIX4_FCH_PM_ADDR,
+ release_mem_region(FCH_PM_BASE,
SB800_PIIX4_FCH_PM_SIZE);
dev_err(dev, "SMBus base address mapping failed.\n");
return -ENOMEM;
@@ -201,7 +201,7 @@ void piix4_sb800_region_release(struct device *dev, struct sb800_mmio_cfg *mmio_
{
if (mmio_cfg->use_mmio) {
iounmap(mmio_cfg->addr);
- release_mem_region(SB800_PIIX4_FCH_PM_ADDR,
+ release_mem_region(FCH_PM_BASE,
SB800_PIIX4_FCH_PM_SIZE);
return;
}
--
2.43.0