[CPUFREQ] Longhaul - Hook into ACPI C states.
Minimal change necessary for hardware support.
Changes in longhaul.c:
- most important - now C3 state is causing transition,
- code responsible for clearing "bus master" bit removed,
- protect bcr2 transition in the same way as longhaul.
Signed-off-by: Rafa³ Bilski <rafalbilski@interia.pl>
Signed-off-by: Dave Jones <davej@redhat.com>
diff --git a/arch/i386/kernel/cpu/cpufreq/Kconfig b/arch/i386/kernel/cpu/cpufreq/Kconfig
index e44a4c6..c593d73 100644
--- a/arch/i386/kernel/cpu/cpufreq/Kconfig
+++ b/arch/i386/kernel/cpu/cpufreq/Kconfig
@@ -202,7 +202,7 @@
config X86_LONGHAUL
tristate "VIA Cyrix III Longhaul"
select CPU_FREQ_TABLE
- depends on BROKEN
+ depends on ACPI_PROCESSOR
help
This adds the CPUFreq driver for VIA Samuel/CyrixIII,
VIA Cyrix Samuel/C3, VIA Cyrix Ezra and VIA Cyrix Ezra-T
diff --git a/arch/i386/kernel/cpu/cpufreq/longhaul.c b/arch/i386/kernel/cpu/cpufreq/longhaul.c
index 146f607..d735cb4 100644
--- a/arch/i386/kernel/cpu/cpufreq/longhaul.c
+++ b/arch/i386/kernel/cpu/cpufreq/longhaul.c
@@ -29,11 +29,13 @@
#include <linux/cpufreq.h>
#include <linux/slab.h>
#include <linux/string.h>
-#include <linux/pci.h>
#include <asm/msr.h>
#include <asm/timex.h>
#include <asm/io.h>
+#include <asm/acpi.h>
+#include <linux/acpi.h>
+#include <acpi/processor.h>
#include "longhaul.h"
@@ -56,6 +58,8 @@
static unsigned int minmult, maxmult;
static int can_scale_voltage;
static int vrmrev;
+static struct acpi_processor *pr = NULL;
+static struct acpi_processor_cx *cx = NULL;
/* Module parameters */
static int dont_scale_voltage;
@@ -118,84 +122,64 @@
return eblcr_table[invalue];
}
+/* For processor with BCR2 MSR */
-static void do_powersaver(union msr_longhaul *longhaul,
- unsigned int clock_ratio_index)
+static void do_longhaul1(int cx_address, unsigned int clock_ratio_index)
{
- struct pci_dev *dev;
- unsigned long flags;
- unsigned int tmp_mask;
- int version;
- int i;
- u16 pci_cmd;
- u16 cmd_state[64];
+ union msr_bcr2 bcr2;
+ u32 t;
- switch (cpu_model) {
- case CPU_EZRA_T:
- version = 3;
- break;
- case CPU_NEHEMIAH:
- version = 0xf;
- break;
- default:
- return;
- }
+ rdmsrl(MSR_VIA_BCR2, bcr2.val);
+ /* Enable software clock multiplier */
+ bcr2.bits.ESOFTBF = 1;
+ bcr2.bits.CLOCKMUL = clock_ratio_index;
- rdmsrl(MSR_VIA_LONGHAUL, longhaul->val);
- longhaul->bits.SoftBusRatio = clock_ratio_index & 0xf;
- longhaul->bits.SoftBusRatio4 = (clock_ratio_index & 0x10) >> 4;
- longhaul->bits.EnableSoftBusRatio = 1;
- longhaul->bits.RevisionKey = 0;
-
- preempt_disable();
- local_irq_save(flags);
-
- /*
- * get current pci bus master state for all devices
- * and clear bus master bit
- */
- dev = NULL;
- i = 0;
- do {
- dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev);
- if (dev != NULL) {
- pci_read_config_word(dev, PCI_COMMAND, &pci_cmd);
- cmd_state[i++] = pci_cmd;
- pci_cmd &= ~PCI_COMMAND_MASTER;
- pci_write_config_word(dev, PCI_COMMAND, pci_cmd);
- }
- } while (dev != NULL);
-
- tmp_mask=inb(0x21); /* works on C3. save mask. */
- outb(0xFE,0x21); /* TMR0 only */
- outb(0xFF,0x80); /* delay */
-
+ /* Sync to timer tick */
safe_halt();
- wrmsrl(MSR_VIA_LONGHAUL, longhaul->val);
- halt();
+ ACPI_FLUSH_CPU_CACHE();
+ /* Change frequency on next halt or sleep */
+ wrmsrl(MSR_VIA_BCR2, bcr2.val);
+ /* Invoke C3 */
+ inb(cx_address);
+ /* Dummy op - must do something useless after P_LVL3 read */
+ t = inl(acpi_fadt.xpm_tmr_blk.address);
+ /* Disable software clock multiplier */
local_irq_disable();
+ rdmsrl(MSR_VIA_BCR2, bcr2.val);
+ bcr2.bits.ESOFTBF = 0;
+ wrmsrl(MSR_VIA_BCR2, bcr2.val);
+}
- outb(tmp_mask,0x21); /* restore mask */
+/* For processor with Longhaul MSR */
- /* restore pci bus master state for all devices */
- dev = NULL;
- i = 0;
- do {
- dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev);
- if (dev != NULL) {
- pci_cmd = cmd_state[i++];
- pci_write_config_byte(dev, PCI_COMMAND, pci_cmd);
- }
- } while (dev != NULL);
- local_irq_restore(flags);
- preempt_enable();
+static void do_powersaver(int cx_address, unsigned int clock_ratio_index)
+{
+ union msr_longhaul longhaul;
+ u32 t;
- /* disable bus ratio bit */
- rdmsrl(MSR_VIA_LONGHAUL, longhaul->val);
- longhaul->bits.EnableSoftBusRatio = 0;
- longhaul->bits.RevisionKey = version;
- wrmsrl(MSR_VIA_LONGHAUL, longhaul->val);
+ rdmsrl(MSR_VIA_LONGHAUL, longhaul.val);
+ longhaul.bits.RevisionKey = longhaul.bits.RevisionID;
+ longhaul.bits.SoftBusRatio = clock_ratio_index & 0xf;
+ longhaul.bits.SoftBusRatio4 = (clock_ratio_index & 0x10) >> 4;
+
+ /* Sync to timer tick */
+ safe_halt();
+ ACPI_FLUSH_CPU_CACHE();
+ /* Change frequency on next halt or sleep */
+ wrmsrl(MSR_VIA_LONGHAUL, longhaul.val);
+ /* Invoke C3 */
+ inb(cx_address);
+ /* Dummy op - must do something useless after P_LVL3 read */
+ t = inl(acpi_fadt.xpm_tmr_blk.address);
+
+ /* Disable bus ratio bit */
+ local_irq_disable();
+ longhaul.bits.RevisionKey = longhaul.bits.RevisionID;
+ longhaul.bits.EnableSoftBusRatio = 0;
+ longhaul.bits.EnableSoftBSEL = 0;
+ longhaul.bits.EnableSoftVID = 0;
+ wrmsrl(MSR_VIA_LONGHAUL, longhaul.val);
}
/**
@@ -209,9 +193,9 @@
{
int speed, mult;
struct cpufreq_freqs freqs;
- union msr_longhaul longhaul;
- union msr_bcr2 bcr2;
static unsigned int old_ratio=-1;
+ unsigned long flags;
+ unsigned int pic1_mask, pic2_mask;
if (old_ratio == clock_ratio_index)
return;
@@ -234,6 +218,20 @@
dprintk ("Setting to FSB:%dMHz Mult:%d.%dx (%s)\n",
fsb, mult/10, mult%10, print_speed(speed/1000));
+ preempt_disable();
+ local_irq_save(flags);
+
+ pic2_mask = inb(0xA1);
+ pic1_mask = inb(0x21); /* works on C3. save mask. */
+ outb(0xFF,0xA1); /* Overkill */
+ outb(0xFE,0x21); /* TMR0 only */
+
+ /* Disable bus master arbitration */
+ if (pr->flags.bm_check) {
+ acpi_set_register(ACPI_BITREG_ARB_DISABLE, 1,
+ ACPI_MTX_DO_NOT_LOCK);
+ }
+
switch (longhaul_version) {
/*
@@ -245,20 +243,7 @@
*/
case TYPE_LONGHAUL_V1:
case TYPE_LONGHAUL_V2:
- rdmsrl (MSR_VIA_BCR2, bcr2.val);
- /* Enable software clock multiplier */
- bcr2.bits.ESOFTBF = 1;
- bcr2.bits.CLOCKMUL = clock_ratio_index;
- local_irq_disable();
- wrmsrl (MSR_VIA_BCR2, bcr2.val);
- safe_halt();
-
- /* Disable software clock multiplier */
- rdmsrl (MSR_VIA_BCR2, bcr2.val);
- bcr2.bits.ESOFTBF = 0;
- local_irq_disable();
- wrmsrl (MSR_VIA_BCR2, bcr2.val);
- local_irq_enable();
+ do_longhaul1(cx->address, clock_ratio_index);
break;
/*
@@ -273,10 +258,22 @@
* to work in practice.
*/
case TYPE_POWERSAVER:
- do_powersaver(&longhaul, clock_ratio_index);
+ do_powersaver(cx->address, clock_ratio_index);
break;
}
+ /* Enable bus master arbitration */
+ if (pr->flags.bm_check) {
+ acpi_set_register(ACPI_BITREG_ARB_DISABLE, 0,
+ ACPI_MTX_DO_NOT_LOCK);
+ }
+
+ outb(pic2_mask,0xA1); /* restore mask */
+ outb(pic1_mask,0x21);
+
+ local_irq_restore(flags);
+ preempt_enable();
+
cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
}
@@ -527,6 +524,18 @@
return calc_speed(longhaul_get_cpu_mult());
}
+acpi_status longhaul_walk_callback(acpi_handle obj_handle,
+ u32 nesting_level,
+ void *context, void **return_value)
+{
+ struct acpi_device *d;
+
+ if ( acpi_bus_get_device(obj_handle, &d) ) {
+ return 0;
+ }
+ *return_value = (void *)acpi_driver_data(d);
+ return 1;
+}
static int __init longhaul_cpu_init(struct cpufreq_policy *policy)
{
@@ -534,6 +543,15 @@
char *cpuname=NULL;
int ret;
+ /* Check ACPI support for C3 state */
+ acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT, ACPI_UINT32_MAX,
+ &longhaul_walk_callback, NULL, (void *)&pr);
+ if (pr == NULL) goto err_acpi;
+
+ cx = &pr->power.states[ACPI_STATE_C3];
+ if (cx == NULL || cx->latency > 1000) goto err_acpi;
+
+ /* Now check what we have on this motherboard */
switch (c->x86_model) {
case 6:
cpu_model = CPU_SAMUEL;
@@ -634,6 +652,10 @@
cpufreq_frequency_table_get_attr(longhaul_table, policy->cpu);
return 0;
+
+err_acpi:
+ printk(KERN_ERR PFX "No ACPI support for CPU frequency changes.\n");
+ return -ENODEV;
}
static int __devexit longhaul_cpu_exit(struct cpufreq_policy *policy)