[PATCH 2/9] watchdog: iTCO: Resolve iTCO_regs on demand

[Jan Kiszka]

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

This avoids having to maintain both itco_version and the version-based
reference into iTCO_version_regs inside iTCO_chipset_info. Make
iTCO_version_regs const at this chance.

Signed-off-by: Jan Kiszka <jan.k...@siemens.com>
---
drivers/watchdog/itco.c | 39 +++++++++++++++++----------------------
1 file changed, 17 insertions(+), 22 deletions(-)

diff --git a/drivers/watchdog/itco.c b/drivers/watchdog/itco.c
index 68c4828..85e9c36 100644
--- a/drivers/watchdog/itco.c
+++ b/drivers/watchdog/itco.c
@@ -1,7 +1,7 @@
/*
- * EFI Boot Guard, iTCO support (Version 3 and later)
+ * EFI Boot Guard, iTCO support (Version 2 and later)
*
- * Copyright (c) Siemens AG, 2019
+ * Copyright (c) Siemens AG, 2019-2021
*
* Authors:
* Jan Kiszka <jan.k...@siemens.com>
@@ -55,11 +55,10 @@ typedef struct {
typedef struct {
CHAR16 name[16];
UINT32 pci_id;
- iTCO_regs* regs;
UINT32 itco_version;
} iTCO_info;

-static iTCO_regs iTCO_version_regs[] = {
+static const iTCO_regs iTCO_version_regs[] = {
[ITCO_V1] =
{
/* Not implemented yet */
@@ -103,56 +102,48 @@ static iTCO_info iTCO_chipset_info[] = {
{
.name = L"Apollo Lake SoC",
.pci_id = 0x5ae8,
- .regs = &iTCO_version_regs[ITCO_V5],
.itco_version = ITCO_V5,
},
[ITCO_INTEL_BAYTRAIL] =
{
.name = L"Bay Trail SoC",
.pci_id = 0x0f1c,
- .regs = &iTCO_version_regs[ITCO_V3],
.itco_version = ITCO_V3,
},
[ITCO_INTEL_WPT_LP] =
{
.name = L"Wildcat Point_LP",
.pci_id = 0x9cc3,
- .regs = &iTCO_version_regs[ITCO_V3],
.itco_version = ITCO_V3,
},
[ITCO_INTEL_ICH9] =
{
.name = L"ICH9", /* QEmu machine q35 */
.pci_id = 0x2918,
- .regs = &iTCO_version_regs[ITCO_V3],
.itco_version = ITCO_V3,
},
[ITCO_INTEL_LPC_NM10] =
{
.name = L"NM10",
.pci_id = 0x27bc,
- .regs = &iTCO_version_regs[ITCO_V2],
.itco_version = ITCO_V2,
},
[ITCO_INTEL_LPC_LP] =
{
.name = L"Lynx Point",
.pci_id = 0x8c4e,
- .regs = &iTCO_version_regs[ITCO_V2],
.itco_version = ITCO_V2,
},
[ITCO_INTEL_WBG] =
{
.name = L"Wellsburg",
.pci_id = 0x8d44,
- .regs = &iTCO_version_regs[ITCO_V2],
.itco_version = ITCO_V2,
},
[ITCO_INTEL_EHL] =
{
.name = L"Elkhart Lake",
.pci_id = 0x4b23,
- .regs = &iTCO_version_regs[ITCO_V6],
.itco_version = ITCO_V6,
},
};
@@ -176,11 +167,12 @@ static UINTN get_timeout_value(UINT32 iTCO_version, UINTN seconds){

static UINT32 get_tco_base(EFI_PCI_IO *pci_io, iTCO_info *itco)
{
+ const iTCO_regs* regs = &iTCO_version_regs[itco->itco_version];
UINT32 pm_base;
EFI_STATUS status;

- if (itco->regs->tco_base) {
- return itco->regs->tco_base;
+ if (regs->tco_base) {
+ return regs->tco_base;
}

status = uefi_call_wrapper(pci_io->Pci.Read, 5, pci_io,
@@ -189,7 +181,7 @@ static UINT32 get_tco_base(EFI_PCI_IO *pci_io, iTCO_info *itco)
Print(L"Error reading PM_BASE: %r\n", status);
return 0;
}
- return (pm_base & itco->regs->pm_base_addr_mask) + 0x60;
+ return (pm_base & regs->pm_base_addr_mask) + 0x60;
}

static EFI_STATUS update_no_reboot_flag_cnt(EFI_PCI_IO *pci_io,
@@ -219,29 +211,30 @@ static EFI_STATUS update_no_reboot_flag_cnt(EFI_PCI_IO *pci_io,
static EFI_STATUS update_no_reboot_flag_mem(EFI_PCI_IO *pci_io,
iTCO_info *itco)
{
+ const iTCO_regs* regs = &iTCO_version_regs[itco->itco_version];
EFI_STATUS status;
UINT32 pmc_base, value;

status =
uefi_call_wrapper(pci_io->Pci.Read, 5, pci_io, EfiPciIoWidthUint32,
- itco->regs->pmc_base_reg, 1, &pmc_base);
+ regs->pmc_base_reg, 1, &pmc_base);
if (EFI_ERROR(status)) {
return status;
}
- pmc_base &= itco->regs->pmc_base_addr_mask;
+ pmc_base &= regs->pmc_base_addr_mask;

status = uefi_call_wrapper(pci_io->Mem.Read, 6, pci_io,
EfiPciIoWidthUint32,
EFI_PCI_IO_PASS_THROUGH_BAR,
- pmc_base + itco->regs->pmc_reg, 1, &value);
+ pmc_base + regs->pmc_reg, 1, &value);
if (EFI_ERROR(status)) {
return status;
}
- value &= ~itco->regs->pmc_no_reboot_mask;
+ value &= ~regs->pmc_no_reboot_mask;
status = uefi_call_wrapper(pci_io->Mem.Write, 6, pci_io,
EfiPciIoWidthUint32,
EFI_PCI_IO_PASS_THROUGH_BAR,
- pmc_base + itco->regs->pmc_reg, 1, &value);
+ pmc_base + regs->pmc_reg, 1, &value);
if (EFI_ERROR(status)) {
return status;
}
@@ -261,6 +254,8 @@ static EFI_STATUS update_no_reboot_flag_apl(__attribute__((unused))
EFI_PCI_IO *pci_io,
iTCO_info *itco)
{
+ const iTCO_regs* regs = &iTCO_version_regs[itco->itco_version];
+
/* Unhide the P2SB device if it's hidden. */
BOOLEAN p2sb_hidden =
*(volatile UINT16 *)apl_mmcfg_address(0, 13, 0, 0) == 0xffff;
@@ -270,9 +265,9 @@ static EFI_STATUS update_no_reboot_flag_apl(__attribute__((unused))

/* Get PMC_BASE from PMC Controller Register. */
volatile UINT8 *reg =
- (volatile UINT8 *)apl_mmcfg_address(0, 13, 1, (UINTN)itco->regs->pmc_reg);
+ (volatile UINT8 *)apl_mmcfg_address(0, 13, 1, (UINTN)regs->pmc_reg);
UINT8 value = *reg;
- value &= ~itco->regs->pmc_no_reboot_mask;
+ value &= ~regs->pmc_no_reboot_mask;
*reg = value;

if (p2sb_hidden) {
--
2.26.2