diff options
Diffstat (limited to 'src/drivers/pc80/tpm.c')
| -rw-r--r-- | src/drivers/pc80/tpm.c | 264 |
1 files changed, 164 insertions, 100 deletions
diff --git a/src/drivers/pc80/tpm.c b/src/drivers/pc80/tpm.c index b8ed3f1635..f581ab49d3 100644 --- a/src/drivers/pc80/tpm.c +++ b/src/drivers/pc80/tpm.c @@ -44,6 +44,10 @@ printk(BIOS_DEBUG, PREFIX); \ printk(BIOS_DEBUG, fmt , ##args); \ } +#define TPM_DEBUG_IO_READ(reg_, val_) \ + TPM_DEBUG("Read reg 0x%x returns 0x%x\n", (reg_), (val_)) +#define TPM_DEBUG_IO_WRITE(reg_, val_) \ + TPM_DEBUG("Write reg 0x%x with 0x%x\n", (reg_), (val_)) #define printf(x...) printk(BIOS_ERR, x) #define min(a,b) MIN(a,b) @@ -70,6 +74,7 @@ #define TIS_REG_INT_STATUS 0x10 #define TIS_REG_INTF_CAPABILITY 0x14 #define TIS_REG_STS 0x18 +#define TIS_REG_BURST_COUNT 0x19 #define TIS_REG_DATA_FIFO 0x24 #define TIS_REG_DID_VID 0xf00 #define TIS_REG_RID 0xf04 @@ -90,9 +95,6 @@ #define TIS_ACCESS_REQUEST_USE (1 << 1) /* 0x02 */ #define TIS_ACCESS_TPM_ESTABLISHMENT (1 << 0) /* 0x01 */ -#define TIS_STS_BURST_COUNT_MASK (0xffff) -#define TIS_STS_BURST_COUNT_SHIFT (8) - /* * Error value returned if a tpm register does not enter the expected state * after continuous polling. No actual TPM register reading ever returns ~0, @@ -107,10 +109,6 @@ /* 1 second is plenty for anything TPM does.*/ #define MAX_DELAY_US (1000 * 1000) -/* Retrieve burst count value out of the status register contents. */ -#define BURST_COUNT(status) ((u16)(((status) >> TIS_STS_BURST_COUNT_SHIFT) & \ - TIS_STS_BURST_COUNT_MASK)) - /* * Structures defined below allow creating descriptions of TPM vendor/device * ID information for run time discovery. The only device the system knows @@ -160,71 +158,165 @@ static const struct vendor_name vendor_names[] = { */ static u32 vendor_dev_id CAR_GLOBAL; -static int is_byte_reg(u32 reg) +static inline u8 tpm_read_status(int locality) { - /* - * These TPM registers are 8 bits wide and as such require byte access - * on writes and truncated value on reads. - */ - return ((reg == TIS_REG_ACCESS) || - (reg == TIS_REG_INT_VECTOR) || - (reg == TIS_REG_DATA_FIFO)); + u8 value = readb(TIS_REG(locality, TIS_REG_STS)); + TPM_DEBUG_IO_READ(TIS_REG_STS, value); + return value; } -/* TPM access functions are carved out to make tracing easier. */ -static u32 tpm_read(int locality, u32 reg) +static inline void tpm_write_status(u8 sts, int locality) { - u32 value; - /* - * Data FIFO register must be read and written in byte access mode, - * otherwise the FIFO values are returned 4 bytes at a time. - */ - if (is_byte_reg(reg)) - value = readb(TIS_REG(locality, reg)); - else - value = readl(TIS_REG(locality, reg)); + TPM_DEBUG_IO_WRITE(TIS_REG_STS, sts); + writeb(sts, TIS_REG(locality, TIS_REG_STS)); +} + +static inline u8 tpm_read_data(int locality) +{ + u8 value = readb(TIS_REG(locality, TIS_REG_DATA_FIFO)); + TPM_DEBUG_IO_READ(TIS_REG_DATA_FIFO, value); + return value; +} + +static inline void tpm_write_data(u8 data, int locality) +{ + TPM_DEBUG_IO_WRITE(TIS_REG_STS, data); + writeb(data, TIS_REG(locality, TIS_REG_DATA_FIFO)); +} - TPM_DEBUG("Read reg 0x%x returns 0x%x\n", reg, value); +static inline u16 tpm_read_burst_count(int locality) +{ + u16 count; + count = readb(TIS_REG(locality, TIS_REG_BURST_COUNT)); + count |= readb(TIS_REG(locality, TIS_REG_BURST_COUNT + 1)) << 8; + TPM_DEBUG_IO_READ(TIS_REG_BURST_COUNT, count); + return count; +} + +static inline u8 tpm_read_access(int locality) +{ + u8 value = readb(TIS_REG(locality, TIS_REG_ACCESS)); + TPM_DEBUG_IO_READ(TIS_REG_ACCESS, value); return value; } -static void tpm_write(u32 value, int locality, u32 reg) +static inline void tpm_write_access(u8 data, int locality) +{ + TPM_DEBUG_IO_WRITE(TIS_REG_ACCESS, data); + writeb(data, TIS_REG(locality, TIS_REG_ACCESS)); +} + +static inline u32 tpm_read_did_vid(int locality) +{ + u32 value = readl(TIS_REG(locality, TIS_REG_DID_VID)); + TPM_DEBUG_IO_READ(TIS_REG_DID_VID, value); + return value; +} + +/* + * tis_wait_sts() + * + * Wait for at least a second for a status to change its state to match the + * expected state. Normally the transition happens within microseconds. + * + * @locality - locality + * @mask - bitmask for the bitfield(s) to watch + * @expected - value the field(s) are supposed to be set to + * + * Returns 0 on success or TPM_TIMEOUT_ERR on timeout. + */ +static int tis_wait_sts(int locality, u8 mask, u8 expected) +{ + u32 time_us = MAX_DELAY_US; + while (time_us > 0) { + u8 value = tpm_read_status(locality); + if ((value & mask) == expected) + return 0; + udelay(1); /* 1 us */ + time_us--; + } + return TPM_TIMEOUT_ERR; +} + +static inline int tis_wait_ready(int locality) +{ + return tis_wait_sts(locality, TIS_STS_COMMAND_READY, + TIS_STS_COMMAND_READY); +} + +static inline int tis_wait_valid(int locality) +{ + return tis_wait_sts(locality, TIS_STS_VALID, TIS_STS_VALID); +} + +static inline int tis_wait_valid_data(int locality) +{ + const u8 has_data = TIS_STS_DATA_AVAILABLE | TIS_STS_VALID; + return tis_wait_sts(locality, has_data, has_data); +} + +static inline int tis_has_valid_data(int locality) { - TPM_DEBUG("Write reg 0x%x with 0x%x\n", reg, value); + const u8 has_data = TIS_STS_DATA_AVAILABLE | TIS_STS_VALID; + return (tpm_read_status(locality) & has_data) == has_data; +} - if (is_byte_reg(reg)) - writeb(value & 0xff, TIS_REG(locality, reg)); - else - writel(value, TIS_REG(locality, reg)); +static inline int tis_expect_data(int locality) +{ + return !!(tpm_read_status(locality) & TIS_STS_EXPECT); } /* - * tis_wait_reg() + * tis_wait_access() * - * Wait for at least a second for a register to change its state to match the + * Wait for at least a second for a access to change its state to match the * expected state. Normally the transition happens within microseconds. * - * @reg - the TPM register offset * @locality - locality * @mask - bitmask for the bitfield(s) to watch * @expected - value the field(s) are supposed to be set to * - * Returns the register contents in case the expected value was found in the - * appropriate register bits, or TPM_TIMEOUT_ERR on timeout. + * Returns 0 on success or TPM_TIMEOUT_ERR on timeout. */ -static u32 tis_wait_reg(u8 reg, u8 locality, u8 mask, u8 expected) +static int tis_wait_access(int locality, u8 mask, u8 expected) { u32 time_us = MAX_DELAY_US; while (time_us > 0) { - u32 value = tpm_read(locality, reg); + u8 value = tpm_read_access(locality); if ((value & mask) == expected) - return value; + return 0; udelay(1); /* 1 us */ time_us--; } return TPM_TIMEOUT_ERR; } +static inline int tis_wait_dropped_access(int locality) +{ + return tis_wait_access(locality, TIS_ACCESS_ACTIVE_LOCALITY, 0); +} + +static inline int tis_wait_received_access(int locality) +{ + return tis_wait_access(locality, TIS_ACCESS_ACTIVE_LOCALITY, + TIS_ACCESS_ACTIVE_LOCALITY); +} + +static inline int tis_has_access(int locality) +{ + return !!(tpm_read_access(locality) & TIS_ACCESS_ACTIVE_LOCALITY); +} + +static inline void tis_request_access(int locality) +{ + tpm_write_access(TIS_ACCESS_REQUEST_USE, locality); +} + +static inline void tis_drop_access(int locality) +{ + tpm_write_access(TIS_ACCESS_ACTIVE_LOCALITY, locality); +} + /* * PC Client Specific TPM Interface Specification section 11.2.12: * @@ -244,23 +336,19 @@ static int tis_command_ready(u8 locality) u32 status; /* 1st attempt to set command ready */ - tpm_write(TIS_STS_COMMAND_READY, locality, TIS_REG_STS); + tpm_write_status(TIS_STS_COMMAND_READY, locality); /* Wait for response */ - status = tpm_read(locality, TIS_REG_STS); + status = tpm_read_status(locality); /* Check if command ready is set yet */ if (status & TIS_STS_COMMAND_READY) return 0; /* 2nd attempt to set command ready */ - tpm_write(TIS_STS_COMMAND_READY, locality, TIS_REG_STS); - - /* Wait for command ready to get set */ - status = tis_wait_reg(TIS_REG_STS, locality, - TIS_STS_COMMAND_READY, TIS_STS_COMMAND_READY); + tpm_write_status(TIS_STS_COMMAND_READY, locality); - return (status == TPM_TIMEOUT_ERR) ? TPM_TIMEOUT_ERR : 0; + return tis_wait_ready(locality); } /* @@ -281,7 +369,7 @@ static u32 tis_probe(void) if (car_get_var(vendor_dev_id)) return 0; /* Already probed. */ - didvid = tpm_read(0, TIS_REG_DID_VID); + didvid = tpm_read_did_vid(0); if (!didvid || (didvid == 0xffffffff)) { printf("%s: No TPM device found\n", __FUNCTION__); return TPM_DRIVER_ERR; @@ -331,16 +419,13 @@ static u32 tis_senddata(const u8 * const data, u32 len) u16 burst = 0; u32 max_cycles = 0; u8 locality = 0; - u32 value; - value = tis_wait_reg(TIS_REG_STS, locality, TIS_STS_COMMAND_READY, - TIS_STS_COMMAND_READY); - if (value == TPM_TIMEOUT_ERR) { + if (tis_wait_ready(locality)) { printf("%s:%d - failed to get 'command_ready' status\n", __FILE__, __LINE__); return TPM_DRIVER_ERR; } - burst = BURST_COUNT(value); + burst = tpm_read_burst_count(locality); while (1) { unsigned count; @@ -353,7 +438,7 @@ static u32 tis_senddata(const u8 * const data, u32 len) return TPM_DRIVER_ERR; } udelay(1); - burst = BURST_COUNT(tpm_read(locality, TIS_REG_STS)); + burst = tpm_read_burst_count(locality); } max_cycles = 0; @@ -369,18 +454,15 @@ static u32 tis_senddata(const u8 * const data, u32 len) */ count = min(burst, len - offset - 1); while (count--) - tpm_write(data[offset++], locality, TIS_REG_DATA_FIFO); + tpm_write_data(data[offset++], locality); - value = tis_wait_reg(TIS_REG_STS, locality, - TIS_STS_VALID, TIS_STS_VALID); - - if ((value == TPM_TIMEOUT_ERR) || !(value & TIS_STS_EXPECT)) { + if (tis_wait_valid(locality) || !tis_expect_data(locality)) { printf("%s:%d TPM command feed overflow\n", __FILE__, __LINE__); return TPM_DRIVER_ERR; } - burst = BURST_COUNT(value); + burst = tpm_read_burst_count(locality); if ((offset == (len - 1)) && burst) /* * We need to be able to send the last byte to the @@ -391,22 +473,20 @@ static u32 tis_senddata(const u8 * const data, u32 len) } /* Send the last byte. */ - tpm_write(data[offset++], locality, TIS_REG_DATA_FIFO); + tpm_write_data(data[offset++], locality); /* * Verify that TPM does not expect any more data as part of this * command. */ - value = tis_wait_reg(TIS_REG_STS, locality, - TIS_STS_VALID, TIS_STS_VALID); - if ((value == TPM_TIMEOUT_ERR) || (value & TIS_STS_EXPECT)) { + if (tis_wait_valid(locality) || tis_expect_data(locality)) { printf("%s:%d unexpected TPM status 0x%x\n", - __FILE__, __LINE__, value); + __FILE__, __LINE__, tpm_read_status(locality)); return TPM_DRIVER_ERR; } /* OK, sitting pretty, let's start the command execution. */ - tpm_write(TIS_STS_TPM_GO, locality, TIS_REG_STS); + tpm_write_status(TIS_STS_TPM_GO, locality); return 0; } @@ -426,37 +506,31 @@ static u32 tis_senddata(const u8 * const data, u32 len) static u32 tis_readresponse(u8 *buffer, size_t *len) { u16 burst_count; - u32 status; u32 offset = 0; u8 locality = 0; - const u32 has_data = TIS_STS_DATA_AVAILABLE | TIS_STS_VALID; u32 expected_count = *len; int max_cycles = 0; /* Wait for the TPM to process the command */ - status = tis_wait_reg(TIS_REG_STS, locality, has_data, has_data); - if (status == TPM_TIMEOUT_ERR) { - printf("%s:%d failed processing command\n", - __FILE__, __LINE__); + if (tis_wait_valid_data(locality)) { + printf("%s:%d failed processing command\n", __FILE__, __LINE__); return TPM_DRIVER_ERR; } do { - while ((burst_count = BURST_COUNT(status)) == 0) { + while ((burst_count = tpm_read_burst_count(locality)) == 0) { if (max_cycles++ == MAX_DELAY_US) { printf("%s:%d TPM stuck on read\n", __FILE__, __LINE__); return TPM_DRIVER_ERR; } udelay(1); - status = tpm_read(locality, TIS_REG_STS); } max_cycles = 0; while (burst_count-- && (offset < expected_count)) { - buffer[offset++] = (u8) tpm_read(locality, - TIS_REG_DATA_FIFO); + buffer[offset++] = tpm_read_data(locality); if (offset == 6) { /* * We got the first six bytes of the reply, @@ -482,9 +556,7 @@ static u32 tis_readresponse(u8 *buffer, size_t *len) } /* Wait for the next portion */ - status = tis_wait_reg(TIS_REG_STS, locality, - TIS_STS_VALID, TIS_STS_VALID); - if (status == TPM_TIMEOUT_ERR) { + if (tis_wait_valid(locality)) { printf("%s:%d failed to read response\n", __FILE__, __LINE__); return TPM_DRIVER_ERR; @@ -493,15 +565,13 @@ static u32 tis_readresponse(u8 *buffer, size_t *len) if (offset == expected_count) break; /* We got all we need */ - } while ((status & has_data) == has_data); + } while (tis_has_valid_data(locality)); - /* - * Make sure we indeed read all there was. The TIS_STS_VALID bit is - * known to be set. - */ - if (status & TIS_STS_DATA_AVAILABLE) { - printf("%s:%d wrong receive status %x\n", - __FILE__, __LINE__, status); + /* * Make sure we indeed read all there was. */ + if (tis_has_valid_data(locality)) { + printf("%s:%d wrong receive status: %x %d bytes left\n", + __FILE__, __LINE__, tpm_read_status(locality), + tpm_read_burst_count(locality)); return TPM_DRIVER_ERR; } @@ -542,12 +612,10 @@ int tis_open(void) return TPM_DRIVER_ERR; /* now request access to locality */ - tpm_write(TIS_ACCESS_REQUEST_USE, locality, TIS_REG_ACCESS); + tis_request_access(locality); /* did we get a lock? */ - if (tis_wait_reg(TIS_REG_ACCESS, locality, - TIS_ACCESS_ACTIVE_LOCALITY, - TIS_ACCESS_ACTIVE_LOCALITY) == TPM_TIMEOUT_ERR) { + if (tis_wait_received_access(locality)) { printf("%s:%d - failed to lock locality %d\n", __FILE__, __LINE__, locality); return TPM_DRIVER_ERR; @@ -572,13 +640,9 @@ int tis_open(void) int tis_close(void) { u8 locality = 0; - if (tpm_read(locality, TIS_REG_ACCESS) & - TIS_ACCESS_ACTIVE_LOCALITY) { - tpm_write(TIS_ACCESS_ACTIVE_LOCALITY, locality, TIS_REG_ACCESS); - - if (tis_wait_reg(TIS_REG_ACCESS, locality, - TIS_ACCESS_ACTIVE_LOCALITY, 0) == - TPM_TIMEOUT_ERR) { + if (tis_has_access(locality)) { + tis_drop_access(locality); + if (tis_wait_dropped_access(locality)) { printf("%s:%d - failed to release locality %d\n", __FILE__, __LINE__, locality); return TPM_DRIVER_ERR; |