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authorTerry Bowman <terry.bowman@amd.com>2022-02-09 11:27:16 -0600
committerWolfram Sang <wsa@kernel.org>2022-02-11 15:38:22 +0100
commit381a3083c6747ae5cdbef9b176d57d1b966db49f (patch)
tree2ae1ec4f0f3e67bc8906baea656a1b9f9e242af9 /drivers/i2c/busses/i2c-piix4.c
parenti2c: piix4: Add EFCH MMIO support to SMBus base address detect (diff)
downloadlinux-dev-381a3083c6747ae5cdbef9b176d57d1b966db49f.tar.xz
linux-dev-381a3083c6747ae5cdbef9b176d57d1b966db49f.zip
i2c: piix4: Add EFCH MMIO support for SMBus port select
AMD processors include registers capable of selecting between 2 SMBus ports. Port selection is made during each user access by writing to FCH::PM::DECODEEN[smbus0sel]. Change the driver to use MMIO during SMBus port selection because cd6h/cd7h port I/O is not available on later AMD processors. Signed-off-by: Terry Bowman <terry.bowman@amd.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Reviewed-by: Jean Delvare <jdelvare@suse.de> Signed-off-by: Wolfram Sang <wsa@kernel.org>
Diffstat (limited to 'drivers/i2c/busses/i2c-piix4.c')
-rw-r--r--drivers/i2c/busses/i2c-piix4.c15
1 files changed, 12 insertions, 3 deletions
diff --git a/drivers/i2c/busses/i2c-piix4.c b/drivers/i2c/busses/i2c-piix4.c
index 7f312177eb27..4789fc9ad270 100644
--- a/drivers/i2c/busses/i2c-piix4.c
+++ b/drivers/i2c/busses/i2c-piix4.c
@@ -753,10 +753,19 @@ static void piix4_imc_wakeup(void)
release_region(KERNCZ_IMC_IDX, 2);
}
-static int piix4_sb800_port_sel(u8 port)
+static int piix4_sb800_port_sel(u8 port, struct sb800_mmio_cfg *mmio_cfg)
{
u8 smba_en_lo, val;
+ if (mmio_cfg->use_mmio) {
+ smba_en_lo = ioread8(mmio_cfg->addr + piix4_port_sel_sb800);
+ val = (smba_en_lo & ~piix4_port_mask_sb800) | port;
+ if (smba_en_lo != val)
+ iowrite8(val, mmio_cfg->addr + piix4_port_sel_sb800);
+
+ return (smba_en_lo & piix4_port_mask_sb800);
+ }
+
outb_p(piix4_port_sel_sb800, SB800_PIIX4_SMB_IDX);
smba_en_lo = inb_p(SB800_PIIX4_SMB_IDX + 1);
@@ -843,12 +852,12 @@ static s32 piix4_access_sb800(struct i2c_adapter *adap, u16 addr,
}
}
- prev_port = piix4_sb800_port_sel(adapdata->port);
+ prev_port = piix4_sb800_port_sel(adapdata->port, &adapdata->mmio_cfg);
retval = piix4_access(adap, addr, flags, read_write,
command, size, data);
- piix4_sb800_port_sel(prev_port);
+ piix4_sb800_port_sel(prev_port, &adapdata->mmio_cfg);
/* Release the semaphore */
outb_p(smbslvcnt | 0x20, SMBSLVCNT);