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 <azhar.shaikh@intel.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
This commit is contained in:
Azhar Shaikh 2017-06-18 19:17:59 -07:00 committed by James Morris
parent f128480f39
commit 5e572cab92
2 changed files with 117 additions and 0 deletions

View File

@ -36,6 +36,10 @@
#include <linux/highmem.h>
#include <crypto/hash_info.h>
#ifdef CONFIG_X86
#include <asm/intel-family.h>
#endif
enum tpm_const {
TPM_MINOR = 224, /* officially assigned */
TPM_BUFSIZE = 4096,

View File

@ -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);
}