diff options
Diffstat (limited to 'drivers/char/tpm/tpm_tis.c')
| -rw-r--r-- | drivers/char/tpm/tpm_tis.c | 154 |
1 files changed, 80 insertions, 74 deletions
diff --git a/drivers/char/tpm/tpm_tis.c b/drivers/char/tpm/tpm_tis.c index d3f2e5364c27..9aa230a63616 100644 --- a/drivers/char/tpm/tpm_tis.c +++ b/drivers/char/tpm/tpm_tis.c @@ -25,9 +25,7 @@ #include <linux/acpi.h> #include <linux/freezer.h> #include <linux/of.h> -#include <linux/of_device.h> #include <linux/kernel.h> -#include <linux/dmi.h> #include "tpm.h" #include "tpm_tis_core.h" @@ -50,8 +48,47 @@ static inline struct tpm_tis_tcg_phy *to_tpm_tis_tcg_phy(struct tpm_tis_data *da return container_of(data, struct tpm_tis_tcg_phy, priv); } -static int interrupts = -1; -module_param(interrupts, int, 0444); +#ifdef CONFIG_PREEMPT_RT +/* + * Flush previous write operations with a dummy read operation to the + * TPM MMIO base address. + */ +static inline void tpm_tis_flush(void __iomem *iobase) +{ + ioread8(iobase + TPM_ACCESS(0)); +} +#else +#define tpm_tis_flush(iobase) do { } while (0) +#endif + +/* + * Write a byte word to the TPM MMIO address, and flush the write queue. + * The flush ensures that the data is sent immediately over the bus and not + * aggregated with further requests and transferred later in a batch. The large + * write requests can lead to unwanted latency spikes by blocking the CPU until + * the complete batch has been transferred. + */ +static inline void tpm_tis_iowrite8(u8 b, void __iomem *iobase, u32 addr) +{ + iowrite8(b, iobase + addr); + tpm_tis_flush(iobase); +} + +/* + * Write a 32-bit word to the TPM MMIO address, and flush the write queue. + * The flush ensures that the data is sent immediately over the bus and not + * aggregated with further requests and transferred later in a batch. The large + * write requests can lead to unwanted latency spikes by blocking the CPU until + * the complete batch has been transferred. + */ +static inline void tpm_tis_iowrite32(u32 b, void __iomem *iobase, u32 addr) +{ + iowrite32(b, iobase + addr); + tpm_tis_flush(iobase); +} + +static bool interrupts; +module_param(interrupts, bool, 0444); MODULE_PARM_DESC(interrupts, "Enable interrupts"); static bool itpm; @@ -64,28 +101,6 @@ module_param(force, bool, 0444); MODULE_PARM_DESC(force, "Force device probe rather than using ACPI entry"); #endif -static int tpm_tis_disable_irq(const struct dmi_system_id *d) -{ - if (interrupts == -1) { - pr_notice("tpm_tis: %s detected: disabling interrupts.\n", d->ident); - interrupts = 0; - } - - return 0; -} - -static const struct dmi_system_id tpm_tis_dmi_table[] = { - { - .callback = tpm_tis_disable_irq, - .ident = "ThinkPad T490s", - .matches = { - DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"), - DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T490s"), - }, - }, - {} -}; - #if defined(CONFIG_PNP) && defined(CONFIG_ACPI) static int has_hid(struct acpi_device *dev, const char *hid) { @@ -125,6 +140,7 @@ static int check_acpi_tpm2(struct device *dev) const struct acpi_device_id *aid = acpi_match_device(tpm_acpi_tbl, dev); struct acpi_table_tpm2 *tbl; acpi_status st; + int ret = 0; if (!aid || aid->driver_data != DEVICE_IS_TPM2) return 0; @@ -132,8 +148,7 @@ static int check_acpi_tpm2(struct device *dev) /* If the ACPI TPM2 signature is matched then a global ACPI_SIG_TPM2 * table is mandatory */ - st = - acpi_get_table(ACPI_SIG_TPM2, 1, (struct acpi_table_header **)&tbl); + st = acpi_get_table(ACPI_SIG_TPM2, 1, (struct acpi_table_header **)&tbl); if (ACPI_FAILURE(st) || tbl->header.length < sizeof(*tbl)) { dev_err(dev, FW_BUG "failed to get TPM2 ACPI table\n"); return -EINVAL; @@ -141,9 +156,10 @@ static int check_acpi_tpm2(struct device *dev) /* The tpm2_crb driver handles this device */ if (tbl->start_method != ACPI_TPM2_MEMORY_MAPPED) - return -ENODEV; + ret = -ENODEV; - return 0; + acpi_put_table((struct acpi_table_header *)tbl); + return ret; } #else static int check_acpi_tpm2(struct device *dev) @@ -153,50 +169,46 @@ static int check_acpi_tpm2(struct device *dev) #endif static int tpm_tcg_read_bytes(struct tpm_tis_data *data, u32 addr, u16 len, - u8 *result) + u8 *result, enum tpm_tis_io_mode io_mode) { struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data); - - while (len--) - *result++ = ioread8(phy->iobase + addr); + __le16 result_le16; + __le32 result_le32; + + switch (io_mode) { + case TPM_TIS_PHYS_8: + while (len--) + *result++ = ioread8(phy->iobase + addr); + break; + case TPM_TIS_PHYS_16: + result_le16 = cpu_to_le16(ioread16(phy->iobase + addr)); + memcpy(result, &result_le16, sizeof(u16)); + break; + case TPM_TIS_PHYS_32: + result_le32 = cpu_to_le32(ioread32(phy->iobase + addr)); + memcpy(result, &result_le32, sizeof(u32)); + break; + } return 0; } static int tpm_tcg_write_bytes(struct tpm_tis_data *data, u32 addr, u16 len, - const u8 *value) -{ - struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data); - - while (len--) - iowrite8(*value++, phy->iobase + addr); - - return 0; -} - -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); - - *result = ioread16(phy->iobase + addr); - - return 0; -} - -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); - - *result = ioread32(phy->iobase + addr); - - return 0; -} - -static int tpm_tcg_write32(struct tpm_tis_data *data, u32 addr, u32 value) + const u8 *value, enum tpm_tis_io_mode io_mode) { struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data); - iowrite32(value, phy->iobase + addr); + switch (io_mode) { + case TPM_TIS_PHYS_8: + while (len--) + tpm_tis_iowrite8(*value++, phy->iobase, addr); + break; + case TPM_TIS_PHYS_16: + return -EINVAL; + case TPM_TIS_PHYS_32: + tpm_tis_iowrite32(le32_to_cpu(*((__le32 *)value)), phy->iobase, addr); + break; + } return 0; } @@ -204,9 +216,6 @@ static int tpm_tcg_write32(struct tpm_tis_data *data, u32 addr, u32 value) static const struct tpm_tis_phy_ops tpm_tcg = { .read_bytes = tpm_tcg_read_bytes, .write_bytes = tpm_tcg_write_bytes, - .read16 = tpm_tcg_read16, - .read32 = tpm_tcg_read32, - .write32 = tpm_tcg_write32, }; static int tpm_tis_init(struct device *dev, struct tpm_info *tpm_info) @@ -215,8 +224,6 @@ static int tpm_tis_init(struct device *dev, struct tpm_info *tpm_info) int irq = -1; int rc; - dmi_check_system(tpm_tis_dmi_table); - rc = check_acpi_tpm2(dev); if (rc) return rc; @@ -233,7 +240,7 @@ static int tpm_tis_init(struct device *dev, struct tpm_info *tpm_info) irq = tpm_info->irq; if (itpm || is_itpm(ACPI_COMPANION(dev))) - phy->priv.flags |= TPM_TIS_ITPM_WORKAROUND; + set_bit(TPM_TIS_ITPM_WORKAROUND, &phy->priv.flags); return tpm_tis_core_init(dev, &phy->priv, irq, &tpm_tcg, ACPI_HANDLE(dev)); @@ -330,18 +337,17 @@ static int tpm_tis_plat_probe(struct platform_device *pdev) return tpm_tis_init(&pdev->dev, &tpm_info); } -static int tpm_tis_plat_remove(struct platform_device *pdev) +static void tpm_tis_plat_remove(struct platform_device *pdev) { struct tpm_chip *chip = dev_get_drvdata(&pdev->dev); tpm_chip_unregister(chip); tpm_tis_remove(chip); - - return 0; } #ifdef CONFIG_OF static const struct of_device_id tis_of_platform_match[] = { + {.compatible = "atmel,at97sc3204"}, {.compatible = "tcg,tpm-tis-mmio"}, {}, }; @@ -423,7 +429,7 @@ static void __exit cleanup_tis(void) module_init(init_tis); module_exit(cleanup_tis); -MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)"); +MODULE_AUTHOR("Leendert van Doorn <leendert@watson.ibm.com>"); MODULE_DESCRIPTION("TPM Driver"); MODULE_VERSION("2.0"); MODULE_LICENSE("GPL"); |