From ef54d5ad2f58f899be6419fd1090cdeb2439851a Mon Sep 17 00:00:00 2001 From: Zhao Yakui Date: Thu, 15 Nov 2007 16:59:30 +0800 Subject: ACPI: Enforce T-state limit changes immediately When a T-state limit change notification is received, Linux must evaluate _TPC and change its current T-state immediately to comply with the new limit. Previously, Linux would notice the new limit only upon the next throttling change. Signed-off-by: Zhao Yakui Signed-off-by: Li Shaohua Signed-off-by: Len Brown --- drivers/acpi/processor_throttling.c | 50 ++++++++++++++++++++++++++++++++++++- 1 file changed, 49 insertions(+), 1 deletion(-) (limited to 'drivers/acpi') diff --git a/drivers/acpi/processor_throttling.c b/drivers/acpi/processor_throttling.c index 0b8204e..5fa8ac1 100644 --- a/drivers/acpi/processor_throttling.c +++ b/drivers/acpi/processor_throttling.c @@ -70,7 +70,55 @@ static int acpi_processor_get_platform_limit(struct acpi_processor *pr) int acpi_processor_tstate_has_changed(struct acpi_processor *pr) { - return acpi_processor_get_platform_limit(pr); + int result = 0; + int throttling_limit; + int current_state; + struct acpi_processor_limit *limit; + int target_state; + + result = acpi_processor_get_platform_limit(pr); + if (result) { + /* Throttling Limit is unsupported */ + return result; + } + + throttling_limit = pr->throttling_platform_limit; + if (throttling_limit >= pr->throttling.state_count) { + /* Uncorrect Throttling Limit */ + return -EINVAL; + } + + current_state = pr->throttling.state; + if (current_state > throttling_limit) { + /* + * The current state can meet the requirement of + * _TPC limit. But it is reasonable that OSPM changes + * t-states from high to low for better performance. + * Of course the limit condition of thermal + * and user should be considered. + */ + limit = &pr->limit; + target_state = throttling_limit; + if (limit->thermal.tx > target_state) + target_state = limit->thermal.tx; + if (limit->user.tx > target_state) + target_state = limit->user.tx; + } else if (current_state == throttling_limit) { + /* + * Unnecessary to change the throttling state + */ + return 0; + } else { + /* + * If the current state is lower than the limit of _TPC, it + * will be forced to switch to the throttling state defined + * by throttling_platfor_limit. + * Because the previous state meets with the limit condition + * of thermal and user, it is unnecessary to check it again. + */ + target_state = throttling_limit; + } + return acpi_processor_set_throttling(pr, target_state); } /* -- cgit v1.1 From 49fbabf56dc715bbb51e59742e82ba762790aac0 Mon Sep 17 00:00:00 2001 From: Zhao Yakui Date: Thu, 15 Nov 2007 17:01:06 +0800 Subject: ACPI: Handle I/O access width requestst that are not a multiple of 8 bits. We've run into BIOS that hand us 4-bit access width requests for T-state control when the code expected only multipls of 8-bits. Round up. Signed-off-by: Zhao Yakui Signed-off-by: Li Shaohua Signed-off-by: Len Brown --- drivers/acpi/osl.c | 25 +++++++++---------------- 1 file changed, 9 insertions(+), 16 deletions(-) (limited to 'drivers/acpi') diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c index aabc6ca..e3a673a 100644 --- a/drivers/acpi/osl.c +++ b/drivers/acpi/osl.c @@ -387,17 +387,14 @@ acpi_status acpi_os_read_port(acpi_io_address port, u32 * value, u32 width) if (!value) value = &dummy; - switch (width) { - case 8: + *value = 0; + if (width <= 8) { *(u8 *) value = inb(port); - break; - case 16: + } else if (width <= 16) { *(u16 *) value = inw(port); - break; - case 32: + } else if (width <= 32) { *(u32 *) value = inl(port); - break; - default: + } else { BUG(); } @@ -408,17 +405,13 @@ EXPORT_SYMBOL(acpi_os_read_port); acpi_status acpi_os_write_port(acpi_io_address port, u32 value, u32 width) { - switch (width) { - case 8: + if (width <= 8) { outb(value, port); - break; - case 16: + } else if (width <= 16) { outw(value, port); - break; - case 32: + } else if (width <= 32) { outl(value, port); - break; - default: + } else { BUG(); } -- cgit v1.1 From 22cc50199d0616f7b002563a0e9117ba479356e1 Mon Sep 17 00:00:00 2001 From: Zhao Yakui Date: Thu, 15 Nov 2007 17:02:03 +0800 Subject: ACPI: If _TSS exists, do not access FADT.duty_width Factor out legacy FADT.duty_width code and run it only in the non _TSS case. Signed-off-by: Zhao Yakui Signed-off-by: Li Shaohua Signed-off-by: Len Brown --- drivers/acpi/processor_throttling.c | 66 ++++++++++++++++++++----------------- 1 file changed, 36 insertions(+), 30 deletions(-) (limited to 'drivers/acpi') diff --git a/drivers/acpi/processor_throttling.c b/drivers/acpi/processor_throttling.c index 5fa8ac1..20d82f55 100644 --- a/drivers/acpi/processor_throttling.c +++ b/drivers/acpi/processor_throttling.c @@ -478,6 +478,40 @@ static int acpi_processor_get_throttling(struct acpi_processor *pr) return pr->throttling.acpi_processor_get_throttling(pr); } +static int acpi_processor_get_fadt_info(struct acpi_processor *pr) +{ + int i, step; + + if (!pr->throttling.address) { + ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling register\n")); + return -EINVAL; + } else if (!pr->throttling.duty_width) { + ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling states\n")); + return -EINVAL; + } + /* TBD: Support duty_cycle values that span bit 4. */ + else if ((pr->throttling.duty_offset + pr->throttling.duty_width) > 4) { + printk(KERN_WARNING PREFIX "duty_cycle spans bit 4\n"); + return -EINVAL; + } + + pr->throttling.state_count = 1 << acpi_gbl_FADT.duty_width; + + /* + * Compute state values. Note that throttling displays a linear power + * performance relationship (at 50% performance the CPU will consume + * 50% power). Values are in 1/10th of a percent to preserve accuracy. + */ + + step = (1000 / pr->throttling.state_count); + + for (i = 0; i < pr->throttling.state_count; i++) { + pr->throttling.states[i].performance = 1000 - step * i; + pr->throttling.states[i].power = 1000 - step * i; + } + return 0; +} + static int acpi_processor_set_throttling_fadt(struct acpi_processor *pr, int state) { @@ -591,8 +625,6 @@ int acpi_processor_set_throttling(struct acpi_processor *pr, int state) int acpi_processor_get_throttling_info(struct acpi_processor *pr) { int result = 0; - int step = 0; - int i = 0; ACPI_DEBUG_PRINT((ACPI_DB_INFO, "pblk_address[0x%08x] duty_offset[%d] duty_width[%d]\n", @@ -611,6 +643,8 @@ int acpi_processor_get_throttling_info(struct acpi_processor *pr) acpi_processor_get_throttling_states(pr) || acpi_processor_get_platform_limit(pr)) { + if (acpi_processor_get_fadt_info(pr)) + return 0; pr->throttling.acpi_processor_get_throttling = &acpi_processor_get_throttling_fadt; pr->throttling.acpi_processor_set_throttling = @@ -624,19 +658,6 @@ int acpi_processor_get_throttling_info(struct acpi_processor *pr) acpi_processor_get_tsd(pr); - if (!pr->throttling.address) { - ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling register\n")); - return 0; - } else if (!pr->throttling.duty_width) { - ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling states\n")); - return 0; - } - /* TBD: Support duty_cycle values that span bit 4. */ - else if ((pr->throttling.duty_offset + pr->throttling.duty_width) > 4) { - printk(KERN_WARNING PREFIX "duty_cycle spans bit 4\n"); - return 0; - } - /* * PIIX4 Errata: We don't support throttling on the original PIIX4. * This shouldn't be an issue as few (if any) mobile systems ever @@ -648,21 +669,6 @@ int acpi_processor_get_throttling_info(struct acpi_processor *pr) return 0; } - pr->throttling.state_count = 1 << acpi_gbl_FADT.duty_width; - - /* - * Compute state values. Note that throttling displays a linear power/ - * performance relationship (at 50% performance the CPU will consume - * 50% power). Values are in 1/10th of a percent to preserve accuracy. - */ - - step = (1000 / pr->throttling.state_count); - - for (i = 0; i < pr->throttling.state_count; i++) { - pr->throttling.states[i].performance = step * i; - pr->throttling.states[i].power = step * i; - } - ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n", pr->throttling.state_count)); -- cgit v1.1 From 0753f6e0a3d9568fb6b8e34753b944d9f8eed05b Mon Sep 17 00:00:00 2001 From: Zhao Yakui Date: Thu, 15 Nov 2007 17:03:46 +0800 Subject: ACPI: throttle: Change internal APIs better handle _PTC Change the function interface for throttling control via PTC. The following functions are concerned: acpi_read_throttling_status() acpi_write_throttling_state() acpi_get_throttling_value() acpi_get_throttling_state() Signed-off-by: Zhao Yakui Signed-off-by: Li Shaohua Signed-off-by: Len Brown --- drivers/acpi/processor_throttling.c | 60 ++++++++++++++++++++++++------------- 1 file changed, 39 insertions(+), 21 deletions(-) (limited to 'drivers/acpi') diff --git a/drivers/acpi/processor_throttling.c b/drivers/acpi/processor_throttling.c index 20d82f55..5c96ef1 100644 --- a/drivers/acpi/processor_throttling.c +++ b/drivers/acpi/processor_throttling.c @@ -376,16 +376,23 @@ static int acpi_processor_get_throttling_fadt(struct acpi_processor *pr) return 0; } -static int acpi_read_throttling_status(struct acpi_processor_throttling - *throttling) +static int acpi_read_throttling_status(struct acpi_processor *pr, + acpi_integer *value) { - int value = -1; + u64 ptc_value; + struct acpi_processor_throttling *throttling; + int ret = -1; + + throttling = &pr->throttling; switch (throttling->status_register.space_id) { case ACPI_ADR_SPACE_SYSTEM_IO: + ptc_value = 0; acpi_os_read_port((acpi_io_address) throttling->status_register. - address, &value, + address, (u32 *) &ptc_value, (u32) throttling->status_register.bit_width * 8); + *value = (acpi_integer) ptc_value; + ret = 0; break; case ACPI_ADR_SPACE_FIXED_HARDWARE: printk(KERN_ERR PREFIX @@ -395,18 +402,22 @@ static int acpi_read_throttling_status(struct acpi_processor_throttling printk(KERN_ERR PREFIX "Unknown addr space %d\n", (u32) (throttling->status_register.space_id)); } - return value; + return ret; } -static int acpi_write_throttling_state(struct acpi_processor_throttling - *throttling, int value) +static int acpi_write_throttling_state(struct acpi_processor *pr, + acpi_integer value) { + u64 ptc_value; + 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; acpi_os_write_port((acpi_io_address) throttling-> - control_register.address, value, + control_register.address, (u32) ptc_value, (u32) throttling->control_register. bit_width * 8); ret = 0; @@ -422,7 +433,8 @@ static int acpi_write_throttling_state(struct acpi_processor_throttling return ret; } -static int acpi_get_throttling_state(struct acpi_processor *pr, int value) +static int acpi_get_throttling_state(struct acpi_processor *pr, + acpi_integer value) { int i; @@ -438,22 +450,26 @@ static int acpi_get_throttling_state(struct acpi_processor *pr, int value) return i; } -static int acpi_get_throttling_value(struct acpi_processor *pr, int state) +static int acpi_get_throttling_value(struct acpi_processor *pr, + int state, acpi_integer *value) { - int value = -1; + int ret = -1; + if (state >= 0 && state <= pr->throttling.state_count) { struct acpi_processor_tx_tss *tx = (struct acpi_processor_tx_tss *)&(pr->throttling. states_tss[state]); - value = tx->control; + *value = tx->control; + ret = 0; } - return value; + return ret; } static int acpi_processor_get_throttling_ptc(struct acpi_processor *pr) { int state = 0; - u32 value = 0; + int ret; + acpi_integer value; if (!pr) return -EINVAL; @@ -463,8 +479,9 @@ static int acpi_processor_get_throttling_ptc(struct acpi_processor *pr) pr->throttling.state = 0; local_irq_disable(); - value = acpi_read_throttling_status(&pr->throttling); - if (value >= 0) { + value = 0; + ret = acpi_read_throttling_status(pr, &value); + if (ret >= 0) { state = acpi_get_throttling_state(pr, value); pr->throttling.state = state; } @@ -588,7 +605,8 @@ static int acpi_processor_set_throttling_fadt(struct acpi_processor *pr, static int acpi_processor_set_throttling_ptc(struct acpi_processor *pr, int state) { - u32 value = 0; + int ret; + acpi_integer value; if (!pr) return -EINVAL; @@ -606,10 +624,10 @@ static int acpi_processor_set_throttling_ptc(struct acpi_processor *pr, return -EPERM; local_irq_disable(); - - value = acpi_get_throttling_value(pr, state); - if (value >= 0) { - acpi_write_throttling_state(&pr->throttling, value); + value = 0; + ret = acpi_get_throttling_value(pr, state, &value); + if (ret >= 0) { + acpi_write_throttling_state(pr, value); pr->throttling.state = state; } local_irq_enable(); -- cgit v1.1 From 9bcb27217344c2c1389db3983a436e19484c2f50 Mon Sep 17 00:00:00 2001 From: Zhao Yakui Date: Thu, 15 Nov 2007 17:05:05 +0800 Subject: 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 Signed-off-by: Li Shaohua Signed-off-by: Len Brown --- drivers/acpi/processor_throttling.c | 42 ++++++++++++++++++++++++++++++------- 1 file changed, 35 insertions(+), 7 deletions(-) (limited to 'drivers/acpi') diff --git a/drivers/acpi/processor_throttling.c b/drivers/acpi/processor_throttling.c index 5c96ef1..f4b5f7d 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: -- cgit v1.1 From 0ac3c571315a53c14d2733564f14ebdb911fe903 Mon Sep 17 00:00:00 2001 From: Zhao Yakui Date: Thu, 15 Nov 2007 17:05:46 +0800 Subject: ACPI: Get throttling info from BIOS only after evaluating _PDC Previously _PDC was evaluated later, and thus we'd not get the chance to tell the BIOS that we can suport FixedHW registers (MSRs) and the BIOS would always ask us to use System I/O access for throttling. Signed-off-by: Zhao Yakui Signed-off-by: Li Shaohua Signed-off-by: Len Brown --- drivers/acpi/processor_core.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) (limited to 'drivers/acpi') diff --git a/drivers/acpi/processor_core.c b/drivers/acpi/processor_core.c index 235a51e..e93318b 100644 --- a/drivers/acpi/processor_core.c +++ b/drivers/acpi/processor_core.c @@ -612,12 +612,6 @@ static int acpi_processor_get_info(struct acpi_processor *pr, unsigned has_uid) request_region(pr->throttling.address, 6, "ACPI CPU throttle"); } -#ifdef CONFIG_CPU_FREQ - acpi_processor_ppc_has_changed(pr); -#endif - acpi_processor_get_throttling_info(pr); - acpi_processor_get_limit_info(pr); - return 0; } @@ -665,6 +659,12 @@ static int __cpuinit acpi_processor_start(struct acpi_device *device) /* _PDC call should be done before doing anything else (if reqd.). */ arch_acpi_processor_init_pdc(pr); acpi_processor_set_pdc(pr); +#ifdef CONFIG_CPU_FREQ + acpi_processor_ppc_has_changed(pr); +#endif + acpi_processor_get_throttling_info(pr); + acpi_processor_get_limit_info(pr); + acpi_processor_power_init(pr, device); -- cgit v1.1 From f79f06ab9f86d7203006d2ec8992ac80df36a34e Mon Sep 17 00:00:00 2001 From: Zhao Yakui Date: Thu, 15 Nov 2007 17:06:36 +0800 Subject: ACPI: Enable MSR (FixedHW) support for T-States Add throttling control via MSR when T-states uses the FixHW Control Status registers. Signed-off-by: Zhao Yakui Signed-off-by: Li Shaohua Signed-off-by: Len Brown --- drivers/acpi/processor_throttling.c | 74 +++++++++++++++++++++++++++++++++++-- 1 file changed, 70 insertions(+), 4 deletions(-) (limited to 'drivers/acpi') diff --git a/drivers/acpi/processor_throttling.c b/drivers/acpi/processor_throttling.c index f4b5f7d..c26c61f 100644 --- a/drivers/acpi/processor_throttling.c +++ b/drivers/acpi/processor_throttling.c @@ -393,6 +393,74 @@ static int acpi_processor_get_throttling_fadt(struct acpi_processor *pr) return 0; } +#ifdef CONFIG_X86 +static int acpi_throttling_rdmsr(struct acpi_processor *pr, + acpi_integer * value) +{ + struct cpuinfo_x86 *c; + u64 msr_high, msr_low; + unsigned int cpu; + u64 msr = 0; + int ret = -1; + + cpu = pr->id; + c = &cpu_data(cpu); + + if ((c->x86_vendor != X86_VENDOR_INTEL) || + !cpu_has(c, X86_FEATURE_ACPI)) { + printk(KERN_ERR PREFIX + "HARDWARE addr space,NOT supported yet\n"); + } else { + msr_low = 0; + msr_high = 0; + rdmsr_on_cpu(cpu, MSR_IA32_THERM_CONTROL, + (u32 *)&msr_low , (u32 *) &msr_high); + msr = (msr_high << 32) | msr_low; + *value = (acpi_integer) msr; + ret = 0; + } + return ret; +} + +static int acpi_throttling_wrmsr(struct acpi_processor *pr, acpi_integer value) +{ + struct cpuinfo_x86 *c; + unsigned int cpu; + int ret = -1; + u64 msr; + + cpu = pr->id; + c = &cpu_data(cpu); + + if ((c->x86_vendor != X86_VENDOR_INTEL) || + !cpu_has(c, X86_FEATURE_ACPI)) { + printk(KERN_ERR PREFIX + "HARDWARE addr space,NOT supported yet\n"); + } else { + msr = value; + wrmsr_on_cpu(cpu, MSR_IA32_THERM_CONTROL, + msr & 0xffffffff, msr >> 32); + ret = 0; + } + return ret; +} +#else +static int acpi_throttling_rdmsr(struct acpi_processor *pr, + acpi_integer * value) +{ + printk(KERN_ERR PREFIX + "HARDWARE addr space,NOT supported yet\n"); + return -1; +} + +static int acpi_throttling_wrmsr(struct acpi_processor *pr, acpi_integer value) +{ + printk(KERN_ERR PREFIX + "HARDWARE addr space,NOT supported yet\n"); + return -1; +} +#endif + static int acpi_read_throttling_status(struct acpi_processor *pr, acpi_integer *value) { @@ -417,8 +485,7 @@ static int acpi_read_throttling_status(struct acpi_processor *pr, ret = 0; break; case ACPI_ADR_SPACE_FIXED_HARDWARE: - printk(KERN_ERR PREFIX - "HARDWARE addr space,NOT supported yet\n"); + ret = acpi_throttling_rdmsr(pr, value); break; default: printk(KERN_ERR PREFIX "Unknown addr space %d\n", @@ -451,8 +518,7 @@ static int acpi_write_throttling_state(struct acpi_processor *pr, ret = 0; break; case ACPI_ADR_SPACE_FIXED_HARDWARE: - printk(KERN_ERR PREFIX - "HARDWARE addr space,NOT supported yet\n"); + ret = acpi_throttling_wrmsr(pr, value); break; default: printk(KERN_ERR PREFIX "Unknown addr space %d\n", -- cgit v1.1