[PATCH 4/9] watchdog: iTCO: Access TCO directly

[Jan Kiszka]

From: Jan Kiszka <jan.k...@siemens.com>

The TCO registers do not belong to the LPC PCI device, they are platform
resources. Consequently, accessing them via the UEFI PCI protocol is not
correct and only happens to not through an error. Using in/out instead
also simplifies the code as those cannot fail.

Signed-off-by: Jan Kiszka <jan.k...@siemens.com>
---
drivers/watchdog/itco.c | 64 +++++++----------------------------------
1 file changed, 11 insertions(+), 53 deletions(-)

diff --git a/drivers/watchdog/itco.c b/drivers/watchdog/itco.c
index 7b14b69..7114978 100644
--- a/drivers/watchdog/itco.c
+++ b/drivers/watchdog/itco.c
@@ -16,6 +16,7 @@
#include <efi.h>
#include <efilib.h>
#include <pci/header.h>
+#include <sys/io.h>

#define TCO_RLD_REG 0x00
#define TCO1_CNT_NO_REBOOT (1 << 0)
@@ -184,28 +185,13 @@ static UINT32 get_tco_base(EFI_PCI_IO *pci_io, const iTCO_info *itco)
return (pm_base & regs->pm_base_addr_mask) + 0x60;
}

-static EFI_STATUS update_no_reboot_flag_cnt(EFI_PCI_IO *pci_io,
- UINT32 tco_base)
+static void update_no_reboot_flag_cnt(UINT32 tco_base)
{
- EFI_STATUS status;
UINT32 value;

- status = uefi_call_wrapper(pci_io->Io.Read, 6, pci_io,
- EfiPciIoWidthUint16,
- EFI_PCI_IO_PASS_THROUGH_BAR,
- tco_base + TCO1_CNT_REG, 1, &value);
- if (EFI_ERROR(status)) {
- return status;
- }
+ value = inw(tco_base + TCO1_CNT_REG);
value &= ~TCO1_CNT_NO_REBOOT;
- status = uefi_call_wrapper(pci_io->Io.Write, 6, pci_io,
- EfiPciIoWidthUint16,
- EFI_PCI_IO_PASS_THROUGH_BAR,
- tco_base + TCO1_CNT_REG, 1, &value);
- if (EFI_ERROR(status)) {
- return status;
- }
- return status;
+ outw(value, tco_base + TCO1_CNT_REG);
}

static EFI_STATUS update_no_reboot_flag_mem(EFI_PCI_IO *pci_io,
@@ -284,7 +270,7 @@ init(EFI_PCI_IO *pci_io, UINT16 pci_vendor_id, UINT16 pci_device_id,
UINT8 itco_chip;
const iTCO_info *itco;
UINT32 tco_base, value;
- EFI_STATUS status;
+ EFI_STATUS status = 0;

if (!pci_io || pci_vendor_id != PCI_VENDOR_ID_INTEL ||
!itco_supported(pci_device_id, &itco_chip)) {
@@ -301,37 +287,18 @@ init(EFI_PCI_IO *pci_io, UINT16 pci_vendor_id, UINT16 pci_device_id,
}

/* Set timer value */
- status = uefi_call_wrapper(pci_io->Io.Read, 6, pci_io,
- EfiPciIoWidthUint16,
- EFI_PCI_IO_PASS_THROUGH_BAR,
- tco_base + TCO_TMR_REG, 1, &value);
- if (EFI_ERROR(status)) {
- return status;
- }
+ value = inw(tco_base + TCO_TMR_REG);
value &= 0xfc00;
value |= get_timeout_value(itco->itco_version, timeout) & 0x3ff;
- status = uefi_call_wrapper(pci_io->Io.Write, 6, pci_io,
- EfiPciIoWidthUint16,
- EFI_PCI_IO_PASS_THROUGH_BAR,
- tco_base + TCO_TMR_REG, 1, &value);
- if (EFI_ERROR(status)) {
- return status;
- }
+ outw(value, tco_base + TCO_TMR_REG);

/* Force reloading of timer value */
- value = 1;
- status = uefi_call_wrapper(pci_io->Io.Write, 6, pci_io,
- EfiPciIoWidthUint16,
- EFI_PCI_IO_PASS_THROUGH_BAR,
- tco_base + TCO_RLD_REG, 1, &value);
- if (EFI_ERROR(status)) {
- return status;
- }
+ outw(1, tco_base + TCO_RLD_REG);

/* Clear NO_REBOOT flag */
switch (itco->itco_version) {
case ITCO_V6:
- status = update_no_reboot_flag_cnt(pci_io, tco_base);
+ update_no_reboot_flag_cnt(tco_base);
break;
case ITCO_V5:
status = update_no_reboot_flag_apl(pci_io, itco);
@@ -346,18 +313,9 @@ init(EFI_PCI_IO *pci_io, UINT16 pci_vendor_id, UINT16 pci_device_id,
}

/* Clear HLT flag to start timer */
- status = uefi_call_wrapper(pci_io->Io.Read, 6, pci_io,
- EfiPciIoWidthUint16,
- EFI_PCI_IO_PASS_THROUGH_BAR,
- tco_base + TCO1_CNT_REG, 1, &value);
- if (EFI_ERROR(status)) {
- return status;
- }
+ value = inw(tco_base + TCO1_CNT_REG);
value &= ~TCO_TMR_HLT_MASK;
- status = uefi_call_wrapper(pci_io->Io.Write, 6, pci_io,
- EfiPciIoWidthUint16,
- EFI_PCI_IO_PASS_THROUGH_BAR,
- tco_base + TCO1_CNT_REG, 1, &value);
+ outw(value, tco_base + TCO1_CNT_REG);

return status;
}
--
2.26.2