From 5e572cab92f0bb56ca1e6e5ee4d807663a7ccbad Mon Sep 17 00:00:00 2001 From: Azhar Shaikh Date: Sun, 18 Jun 2017 19:17:59 -0700 Subject: [PATCH] tpm: Enable CLKRUN protocol for Braswell systems To overcome a hardware limitation on Intel Braswell systems, disable CLKRUN protocol during TPM transactions and re-enable once the transaction is completed. Signed-off-by: Azhar Shaikh Reviewed-by: Jarkko Sakkinen Tested-by: Jarkko Sakkinen Signed-off-by: Jarkko Sakkinen Signed-off-by: James Morris --- drivers/char/tpm/tpm.h | 4 ++ drivers/char/tpm/tpm_tis.c | 113 +++++++++++++++++++++++++++++++++++++ 2 files changed, 117 insertions(+) diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h index 1df0521138d3..cdd261383dea 100644 --- a/drivers/char/tpm/tpm.h +++ b/drivers/char/tpm/tpm.h @@ -36,6 +36,10 @@ #include #include +#ifdef CONFIG_X86 +#include +#endif + enum tpm_const { TPM_MINOR = 224, /* officially assigned */ TPM_BUFSIZE = 4096, diff --git a/drivers/char/tpm/tpm_tis.c b/drivers/char/tpm/tpm_tis.c index b14d4aa97af8..d97ce22267fb 100644 --- a/drivers/char/tpm/tpm_tis.c +++ b/drivers/char/tpm/tpm_tis.c @@ -132,13 +132,93 @@ static int check_acpi_tpm2(struct device *dev) } #endif +#ifdef CONFIG_X86 +#define INTEL_LEGACY_BLK_BASE_ADDR 0xFED08000 +#define ILB_REMAP_SIZE 0x100 +#define LPC_CNTRL_REG_OFFSET 0x84 +#define LPC_CLKRUN_EN (1 << 2) + +void __iomem *ilb_base_addr; + +static inline bool is_bsw(void) +{ + return ((boot_cpu_data.x86_model == INTEL_FAM6_ATOM_AIRMONT) ? 1 : 0); +} + +/** + * tpm_platform_begin_xfer() - clear LPC CLKRUN_EN i.e. clocks will be running + */ +static void tpm_platform_begin_xfer(void) +{ + u32 clkrun_val; + + if (!is_bsw()) + return; + + clkrun_val = ioread32(ilb_base_addr + LPC_CNTRL_REG_OFFSET); + + /* Disable LPC CLKRUN# */ + clkrun_val &= ~LPC_CLKRUN_EN; + iowrite32(clkrun_val, ilb_base_addr + LPC_CNTRL_REG_OFFSET); + + /* + * Write any random value on port 0x80 which is on LPC, to make + * sure LPC clock is running before sending any TPM command. + */ + outb(0xCC, 0x80); + +} + +/** + * tpm_platform_end_xfer() - set LPC CLKRUN_EN i.e. clocks can be turned off + */ +static void tpm_platform_end_xfer(void) +{ + u32 clkrun_val; + + if (!is_bsw()) + return; + + clkrun_val = ioread32(ilb_base_addr + LPC_CNTRL_REG_OFFSET); + + /* Enable LPC CLKRUN# */ + clkrun_val |= LPC_CLKRUN_EN; + iowrite32(clkrun_val, ilb_base_addr + LPC_CNTRL_REG_OFFSET); + + /* + * Write any random value on port 0x80 which is on LPC, to make + * sure LPC clock is running before sending any TPM command. + */ + outb(0xCC, 0x80); + +} +#else +static inline bool is_bsw(void) +{ + return false; +} + +static void tpm_platform_begin_xfer(void) +{ +} + +static void tpm_platform_end_xfer(void) +{ +} +#endif + static int tpm_tcg_read_bytes(struct tpm_tis_data *data, u32 addr, u16 len, u8 *result) { struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data); + tpm_platform_begin_xfer(); + while (len--) *result++ = ioread8(phy->iobase + addr); + + tpm_platform_end_xfer(); + return 0; } @@ -147,8 +227,13 @@ static int tpm_tcg_write_bytes(struct tpm_tis_data *data, u32 addr, u16 len, { struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data); + tpm_platform_begin_xfer(); + while (len--) iowrite8(*value++, phy->iobase + addr); + + tpm_platform_end_xfer(); + return 0; } @@ -156,7 +241,12 @@ static int tpm_tcg_read16(struct tpm_tis_data *data, u32 addr, u16 *result) { struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data); + tpm_platform_begin_xfer(); + *result = ioread16(phy->iobase + addr); + + tpm_platform_end_xfer(); + return 0; } @@ -164,7 +254,12 @@ static int tpm_tcg_read32(struct tpm_tis_data *data, u32 addr, u32 *result) { struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data); + tpm_platform_begin_xfer(); + *result = ioread32(phy->iobase + addr); + + tpm_platform_end_xfer(); + return 0; } @@ -172,7 +267,12 @@ static int tpm_tcg_write32(struct tpm_tis_data *data, u32 addr, u32 value) { struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data); + tpm_platform_begin_xfer(); + iowrite32(value, phy->iobase + addr); + + tpm_platform_end_xfer(); + return 0; } @@ -360,6 +460,11 @@ static int __init init_tis(void) if (rc) goto err_force; +#ifdef CONFIG_X86 + if (is_bsw()) + ilb_base_addr = ioremap(INTEL_LEGACY_BLK_BASE_ADDR, + ILB_REMAP_SIZE); +#endif rc = platform_driver_register(&tis_drv); if (rc) goto err_platform; @@ -378,6 +483,10 @@ err_pnp: err_platform: if (force_pdev) platform_device_unregister(force_pdev); +#ifdef CONFIG_X86 + if (is_bsw()) + iounmap(ilb_base_addr); +#endif err_force: return rc; } @@ -387,6 +496,10 @@ static void __exit cleanup_tis(void) pnp_unregister_driver(&tis_pnp_driver); platform_driver_unregister(&tis_drv); +#ifdef CONFIG_X86 + if (is_bsw()) + iounmap(ilb_base_addr); +#endif if (force_pdev) platform_device_unregister(force_pdev); }