[PATCH 5.15 009/132] i2c: piix4: Add EFCH MMIO support to region request and release

Greg Kroah-Hartman
2022-05-23T17:29:12Z

From: Terry Bowman <terry.bowman@amd.com>

commit 7c148722d074c29fb998578eea5de3c14b9608c9 upstream.

EFCH cd6h/cd7h port I/O may no longer be available on later AMD
processors and it is recommended to use MMIO instead. Update the
request and release functions to support MMIO.

MMIO request/release and mmapping require details during cleanup.
Add a MMIO configuration structure containing resource and vaddress
details for mapping the region, accessing the region, and releasing
the region.

Signed-off-by: Terry Bowman <terry.bowman@amd.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
[wsa: rebased after fixup in previous patch]
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Cc: Mario Limonciello <Mario.Limonciello@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/i2c/busses/i2c-piix4.c | 66 ++++++++++++++++++++++++++++++++++++-----
1 file changed, 58 insertions(+), 8 deletions(-)

--- a/drivers/i2c/busses/i2c-piix4.c
+++ b/drivers/i2c/busses/i2c-piix4.c
@@ -98,6 +98,9 @@
#define SB800_PIIX4_PORT_IDX_MASK_KERNCZ 0x18
#define SB800_PIIX4_PORT_IDX_SHIFT_KERNCZ 3

+#define SB800_PIIX4_FCH_PM_ADDR 0xFED80300
+#define SB800_PIIX4_FCH_PM_SIZE 8
+
/* insmod parameters */

/* If force is set to anything different from 0, we forcibly enable the
@@ -156,6 +159,12 @@ static const char *piix4_main_port_names
};
static const char *piix4_aux_port_name_sb800 = " port 1";

+struct sb800_mmio_cfg {
+ void __iomem *addr;
+ struct resource *res;
+ bool use_mmio;
+};
+
struct i2c_piix4_adapdata {
unsigned short smba;

@@ -163,10 +172,40 @@ struct i2c_piix4_adapdata {
bool sb800_main;
bool notify_imc;
u8 port; /* Port number, shifted */
+ struct sb800_mmio_cfg mmio_cfg;
};

-static int piix4_sb800_region_request(struct device *dev)
+static int piix4_sb800_region_request(struct device *dev,
+ struct sb800_mmio_cfg *mmio_cfg)
{
+ if (mmio_cfg->use_mmio) {
+ struct resource *res;
+ void __iomem *addr;
+
+ res = request_mem_region_muxed(SB800_PIIX4_FCH_PM_ADDR,
+ SB800_PIIX4_FCH_PM_SIZE,
+ "sb800_piix4_smb");
+ if (!res) {
+ dev_err(dev,
+ "SMBus base address memory region 0x%x already in use.\n",
+ SB800_PIIX4_FCH_PM_ADDR);
+ return -EBUSY;
+ }
+
+ addr = ioremap(SB800_PIIX4_FCH_PM_ADDR,
+ SB800_PIIX4_FCH_PM_SIZE);
+ if (!addr) {
+ release_resource(res);
+ dev_err(dev, "SMBus base address mapping failed.\n");
+ return -ENOMEM;
+ }
+
+ mmio_cfg->res = res;
+ mmio_cfg->addr = addr;
+
+ return 0;
+ }
+
if (!request_muxed_region(SB800_PIIX4_SMB_IDX, SB800_PIIX4_SMB_MAP_SIZE,
"sb800_piix4_smb")) {
dev_err(dev,
@@ -178,8 +217,15 @@ static int piix4_sb800_region_request(st
return 0;
}

-static void piix4_sb800_region_release(struct device *dev)
+static void piix4_sb800_region_release(struct device *dev,
+ struct sb800_mmio_cfg *mmio_cfg)
{
+ if (mmio_cfg->use_mmio) {
+ iounmap(mmio_cfg->addr);
+ release_resource(mmio_cfg->res);
+ return;
+ }
+
release_region(SB800_PIIX4_SMB_IDX, SB800_PIIX4_SMB_MAP_SIZE);
}

@@ -288,11 +334,13 @@ static int piix4_setup_sb800_smba(struct
u8 *smb_en_status,
unsigned short *piix4_smba)
{
+ struct sb800_mmio_cfg mmio_cfg;
u8 smba_en_lo;
u8 smba_en_hi;
int retval;

- retval = piix4_sb800_region_request(&PIIX4_dev->dev);
+ mmio_cfg.use_mmio = 0;
+ retval = piix4_sb800_region_request(&PIIX4_dev->dev, &mmio_cfg);
if (retval)
return retval;

@@ -301,7 +349,7 @@ static int piix4_setup_sb800_smba(struct
outb_p(smb_en + 1, SB800_PIIX4_SMB_IDX);
smba_en_hi = inb_p(SB800_PIIX4_SMB_IDX + 1);

- piix4_sb800_region_release(&PIIX4_dev->dev);
+ piix4_sb800_region_release(&PIIX4_dev->dev, &mmio_cfg);

if (!smb_en) {
*smb_en_status = smba_en_lo & 0x10;
@@ -328,6 +376,7 @@ static int piix4_setup_sb800(struct pci_
unsigned short piix4_smba;
u8 smb_en, smb_en_status, port_sel;
u8 i2ccfg, i2ccfg_offset = 0x10;
+ struct sb800_mmio_cfg mmio_cfg;
int retval;

/* SB800 and later SMBus does not support forcing address */
@@ -407,7 +456,8 @@ static int piix4_setup_sb800(struct pci_
piix4_port_shift_sb800 = SB800_PIIX4_PORT_IDX_SHIFT;
}
} else {
- retval = piix4_sb800_region_request(&PIIX4_dev->dev);
+ mmio_cfg.use_mmio = 0;
+ retval = piix4_sb800_region_request(&PIIX4_dev->dev, &mmio_cfg);
if (retval) {
release_region(piix4_smba, SMBIOSIZE);
return retval;
@@ -420,7 +470,7 @@ static int piix4_setup_sb800(struct pci_
SB800_PIIX4_PORT_IDX;
piix4_port_mask_sb800 = SB800_PIIX4_PORT_IDX_MASK;
piix4_port_shift_sb800 = SB800_PIIX4_PORT_IDX_SHIFT;
- piix4_sb800_region_release(&PIIX4_dev->dev);
+ piix4_sb800_region_release(&PIIX4_dev->dev, &mmio_cfg);
}

dev_info(&PIIX4_dev->dev,
@@ -731,7 +781,7 @@ static s32 piix4_access_sb800(struct i2c
u8 prev_port;
int retval;

- retval = piix4_sb800_region_request(&adap->dev);
+ retval = piix4_sb800_region_request(&adap->dev, &adapdata->mmio_cfg);
if (retval)
return retval;

@@ -802,7 +852,7 @@ static s32 piix4_access_sb800(struct i2c
piix4_imc_wakeup();

release:
- piix4_sb800_region_release(&adap->dev);
+ piix4_sb800_region_release(&adap->dev, &adapdata->mmio_cfg);
return retval;
}