[PATCH 20/32] drivers/ata: Stop using 32-bit MSR interfaces

From: Juergen Gross

Date: Mon Jun 29 2026 - 02:09:38 EST


The 32-bit MSR interfaces rdmsr() and wrmsr() are planned to be
removed. Use the related 64-bit variants instead.

In drivers/ata/pata_cs5536.c don't redefine rdmsr() and wrmsr() as
empty macros for avoiding misuse, but guard the affected code via

Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
---
drivers/ata/pata_cs5535.c | 20 ++++++++++----------
drivers/ata/pata_cs5536.c | 17 ++++++++---------
2 files changed, 18 insertions(+), 19 deletions(-)

diff --git a/drivers/ata/pata_cs5535.c b/drivers/ata/pata_cs5535.c
index d793fc441b46..da98390cc49e 100644
--- a/drivers/ata/pata_cs5535.c
+++ b/drivers/ata/pata_cs5535.c
@@ -90,7 +90,7 @@ static void cs5535_set_piomode(struct ata_port *ap, struct ata_device *adev)
static const u16 pio_cmd_timings[5] = {
0xF7F4, 0x53F3, 0x13F1, 0x5131, 0x1131
};
- u32 reg, __maybe_unused dummy;
+ u32 reg;
struct ata_device *pair = ata_dev_pair(adev);

int mode = adev->pio_mode - XFER_PIO_0;
@@ -102,16 +102,16 @@ static void cs5535_set_piomode(struct ata_port *ap, struct ata_device *adev)
cmdmode = min(mode, pairmode);
/* Write the other drive timing register if it changed */
if (cmdmode < pairmode)
- wrmsr(ATAC_CH0D0_PIO + 2 * pair->devno,
- pio_cmd_timings[cmdmode] << 16 | pio_timings[pairmode], 0);
+ wrmsrq(ATAC_CH0D0_PIO + 2 * pair->devno,
+ pio_cmd_timings[cmdmode] << 16 | pio_timings[pairmode]);
}
/* Write the drive timing register */
- wrmsr(ATAC_CH0D0_PIO + 2 * adev->devno,
- pio_cmd_timings[cmdmode] << 16 | pio_timings[mode], 0);
+ wrmsrq(ATAC_CH0D0_PIO + 2 * adev->devno,
+ pio_cmd_timings[cmdmode] << 16 | pio_timings[mode]);

/* Set the PIO "format 1" bit in the DMA timing register */
- rdmsr(ATAC_CH0D0_DMA + 2 * adev->devno, reg, dummy);
- wrmsr(ATAC_CH0D0_DMA + 2 * adev->devno, reg | 0x80000000UL, 0);
+ rdmsrq(ATAC_CH0D0_DMA + 2 * adev->devno, reg);
+ wrmsrq(ATAC_CH0D0_DMA + 2 * adev->devno, reg | 0x80000000UL);
}

/**
@@ -129,16 +129,16 @@ static void cs5535_set_dmamode(struct ata_port *ap, struct ata_device *adev)
static const u32 mwdma_timings[3] = {
0x7F0FFFF3, 0x7F035352, 0x7F024241
};
- u32 reg, __maybe_unused dummy;
+ u32 reg;
int mode = adev->dma_mode;

- rdmsr(ATAC_CH0D0_DMA + 2 * adev->devno, reg, dummy);
+ rdmsrq(ATAC_CH0D0_DMA + 2 * adev->devno, reg);
reg &= 0x80000000UL;
if (mode >= XFER_UDMA_0)
reg |= udma_timings[mode - XFER_UDMA_0];
else
reg |= mwdma_timings[mode - XFER_MW_DMA_0];
- wrmsr(ATAC_CH0D0_DMA + 2 * adev->devno, reg, 0);
+ wrmsrq(ATAC_CH0D0_DMA + 2 * adev->devno, reg);
}

static const struct scsi_host_template cs5535_sht = {
diff --git a/drivers/ata/pata_cs5536.c b/drivers/ata/pata_cs5536.c
index 73e81e160c91..61d232a82b5e 100644
--- a/drivers/ata/pata_cs5536.c
+++ b/drivers/ata/pata_cs5536.c
@@ -32,11 +32,8 @@
static int use_msr;
module_param_named(msr, use_msr, int, 0644);
MODULE_PARM_DESC(msr, "Force using MSR to configure IDE function (Default: 0)");
+#define MAYBE_USE_MSR
#else
-#undef rdmsr /* avoid accidental MSR usage on, e.g. x86-64 */
-#undef wrmsr
-#define rdmsr(x, y, z) do { } while (0)
-#define wrmsr(x, y, z) do { } while (0)
#define use_msr 0
#endif

@@ -85,22 +82,24 @@ static const struct dmi_system_id udma_quirk_dmi_table[] = {

static int cs5536_read(struct pci_dev *pdev, int reg, u32 *val)
{
+#ifdef MAYBE_USE_MSR
if (unlikely(use_msr)) {
- u32 dummy __maybe_unused;
-
- rdmsr(MSR_IDE_CFG + reg, *val, dummy);
+ rdmsrq(MSR_IDE_CFG + reg, *val);
return 0;
}
+#endif

return pci_read_config_dword(pdev, PCI_IDE_CFG + reg * 4, val);
}

-static int cs5536_write(struct pci_dev *pdev, int reg, int val)
+static int cs5536_write(struct pci_dev *pdev, int reg, u32 val)
{
+#ifdef MAYBE_USE_MSR
if (unlikely(use_msr)) {
- wrmsr(MSR_IDE_CFG + reg, val, 0);
+ wrmsrq(MSR_IDE_CFG + reg, val);
return 0;
}
+#endif

return pci_write_config_dword(pdev, PCI_IDE_CFG + reg * 4, val);
}
--
2.54.0