diff options
| author | Zhao Yakui <yakui.zhao@intel.com> | 2007-11-15 12:05:05 +0300 |
|---|---|---|
| committer | Len Brown <len.brown@intel.com> | 2007-11-17 05:43:21 +0300 |
| commit | 9bcb27217344c2c1389db3983a436e19484c2f50 (patch) | |
| tree | 14c28cade53f8f64755f3d660149c3c7d501fd1d /drivers/acpi/processor_throttling.c | |
| parent | 0753f6e0a3d9568fb6b8e34753b944d9f8eed05b (diff) | |
| download | linux-9bcb27217344c2c1389db3983a436e19484c2f50.tar.xz | |
ACPI: Use _TSS for throttling control, when present. Add error checks.
_TSS was erroneously ignored, in favor of the FADT.
When TSS is used, the access width is included in the PTC control/status
register. So it is unnecessary that the access bit width is multiplied by 8.
At the same time the bit_offset should be considered for system I/O Access.
It should be checked the bit_width and bit_offset of PTC regsiter in order to
avoid the failure of system I/O access. It means that bit_width plus
bit_offset can't be greater than 32.
Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Signed-off-by: Li Shaohua <shaohua.li@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Diffstat (limited to 'drivers/acpi/processor_throttling.c')
| -rw-r--r-- | drivers/acpi/processor_throttling.c | 42 |
1 files changed, 35 insertions, 7 deletions
diff --git a/drivers/acpi/processor_throttling.c b/drivers/acpi/processor_throttling.c index 5c96ef18e94c..f4b5f7d5dbe6 100644 --- a/drivers/acpi/processor_throttling.c +++ b/drivers/acpi/processor_throttling.c @@ -131,6 +131,7 @@ static int acpi_processor_get_throttling_control(struct acpi_processor *pr) struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; union acpi_object *ptc = NULL; union acpi_object obj = { 0 }; + struct acpi_processor_throttling *throttling; status = acpi_evaluate_object(pr->handle, "_PTC", NULL, &buffer); if (ACPI_FAILURE(status)) { @@ -182,6 +183,22 @@ static int acpi_processor_get_throttling_control(struct acpi_processor *pr) memcpy(&pr->throttling.status_register, obj.buffer.pointer, sizeof(struct acpi_ptc_register)); + throttling = &pr->throttling; + + if ((throttling->control_register.bit_width + + throttling->control_register.bit_offset) > 32) { + printk(KERN_ERR PREFIX "Invalid _PTC control register\n"); + result = -EFAULT; + goto end; + } + + if ((throttling->status_register.bit_width + + throttling->status_register.bit_offset) > 32) { + printk(KERN_ERR PREFIX "Invalid _PTC status register\n"); + result = -EFAULT; + goto end; + } + end: kfree(buffer.pointer); @@ -379,7 +396,9 @@ static int acpi_processor_get_throttling_fadt(struct acpi_processor *pr) static int acpi_read_throttling_status(struct acpi_processor *pr, acpi_integer *value) { + u32 bit_width, bit_offset; u64 ptc_value; + u64 ptc_mask; struct acpi_processor_throttling *throttling; int ret = -1; @@ -387,11 +406,14 @@ static int acpi_read_throttling_status(struct acpi_processor *pr, switch (throttling->status_register.space_id) { case ACPI_ADR_SPACE_SYSTEM_IO: ptc_value = 0; + bit_width = throttling->status_register.bit_width; + bit_offset = throttling->status_register.bit_offset; + acpi_os_read_port((acpi_io_address) throttling->status_register. address, (u32 *) &ptc_value, - (u32) throttling->status_register.bit_width * - 8); - *value = (acpi_integer) ptc_value; + (u32) (bit_width + bit_offset)); + ptc_mask = (1 << bit_width) - 1; + *value = (acpi_integer) ((ptc_value >> bit_offset) & ptc_mask); ret = 0; break; case ACPI_ADR_SPACE_FIXED_HARDWARE: @@ -408,18 +430,24 @@ static int acpi_read_throttling_status(struct acpi_processor *pr, static int acpi_write_throttling_state(struct acpi_processor *pr, acpi_integer value) { + u32 bit_width, bit_offset; u64 ptc_value; + u64 ptc_mask; struct acpi_processor_throttling *throttling; int ret = -1; throttling = &pr->throttling; switch (throttling->control_register.space_id) { case ACPI_ADR_SPACE_SYSTEM_IO: - ptc_value = value; + bit_width = throttling->control_register.bit_width; + bit_offset = throttling->control_register.bit_offset; + ptc_mask = (1 << bit_width) - 1; + ptc_value = value & ptc_mask; + acpi_os_write_port((acpi_io_address) throttling-> - control_register.address, (u32) ptc_value, - (u32) throttling->control_register. - bit_width * 8); + control_register.address, + (u32) (ptc_value << bit_offset), + (u32) (bit_width + bit_offset)); ret = 0; break; case ACPI_ADR_SPACE_FIXED_HARDWARE: |