1 files changed, 69 insertions, 24 deletions

diff --git a/arch/i386/kernel/cpu/cpufreq/longhaul.c b/arch/i386/kernel/cpu/cpufreq/longhaul.c
index 4f2c3aeef724..43bbf948d45d 100644
--- a/arch/i386/kernel/cpu/cpufreq/longhaul.c
+++ b/arch/i386/kernel/cpu/cpufreq/longhaul.c
@@ -27,6 +27,7 @@
 #include <linux/moduleparam.h>
 #include <linux/init.h>
 #include <linux/cpufreq.h>
+#include <linux/pci.h>
 #include <linux/slab.h>
 #include <linux/string.h>
 
@@ -60,10 +61,11 @@ static int can_scale_voltage;
 static int vrmrev;
 static struct acpi_processor *pr = NULL;
 static struct acpi_processor_cx *cx = NULL;
+static int port22_en = 0;
 
 /* Module parameters */
 static int dont_scale_voltage;
-
+static int ignore_latency = 0;
 
 #define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_DRIVER, "longhaul", msg)
 
@@ -124,10 +126,9 @@ static int longhaul_get_cpu_mult(void)
 
 /* For processor with BCR2 MSR */
 
-static void do_longhaul1(int cx_address, unsigned int clock_ratio_index)
+static void do_longhaul1(unsigned int clock_ratio_index)
 {
         union msr_bcr2 bcr2;
-        u32 t;
 
         rdmsrl(MSR_VIA_BCR2, bcr2.val);
         /* Enable software clock multiplier */
@@ -136,13 +137,11 @@ static void do_longhaul1(int cx_address, unsigned int clock_ratio_index)
 
         /* Sync to timer tick */
         safe_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);
+        /* Invoke transition */
+        ACPI_FLUSH_CPU_CACHE();
+        halt();
 
         /* Disable software clock multiplier */
         local_irq_disable();
@@ -166,9 +165,9 @@ static void do_powersaver(int cx_address, unsigned int clock_ratio_index)
 
         /* Sync to timer tick */
         safe_halt();
-        ACPI_FLUSH_CPU_CACHE();
         /* Change frequency on next halt or sleep */
         wrmsrl(MSR_VIA_LONGHAUL, longhaul.val);
+        ACPI_FLUSH_CPU_CACHE();
         /* Invoke C3 */
         inb(cx_address);
         /* Dummy op - must do something useless after P_LVL3 read */
@@ -227,10 +226,13 @@ static void longhaul_setstate(unsigned int clock_ratio_index)
         outb(0xFF,0xA1);        /* Overkill */
         outb(0xFE,0x21);        /* TMR0 only */
 
-        /* Disable bus master arbitration */
-        if (pr->flags.bm_check) {
+        if (pr->flags.bm_control) {
+                /* Disable bus master arbitration */
                 acpi_set_register(ACPI_BITREG_ARB_DISABLE, 1,
                                   ACPI_MTX_DO_NOT_LOCK);
+        } else if (port22_en) {
+                /* Disable AGP and PCI arbiters */
+                outb(3, 0x22);
         }
 
         switch (longhaul_version) {
@@ -244,7 +246,7 @@ static void longhaul_setstate(unsigned int clock_ratio_index)
          */
         case TYPE_LONGHAUL_V1:
         case TYPE_LONGHAUL_V2:
-                do_longhaul1(cx->address, clock_ratio_index);
+                do_longhaul1(clock_ratio_index);
                 break;
 
         /*
@@ -259,14 +261,20 @@ static void longhaul_setstate(unsigned int clock_ratio_index)
          * to work in practice.
          */
         case TYPE_POWERSAVER:
+                /* Don't allow wakeup */
+                acpi_set_register(ACPI_BITREG_BUS_MASTER_RLD, 0,
+                                  ACPI_MTX_DO_NOT_LOCK);
                 do_powersaver(cx->address, clock_ratio_index);
                 break;
         }
 
-        /* Enable bus master arbitration */
-        if (pr->flags.bm_check) {
+        if (pr->flags.bm_control) {
+                /* Enable bus master arbitration */
                 acpi_set_register(ACPI_BITREG_ARB_DISABLE, 0,
                                   ACPI_MTX_DO_NOT_LOCK);
+        } else if (port22_en) {
+                /* Enable arbiters */
+                outb(0, 0x22);
         }
 
         outb(pic2_mask,0xA1);   /* restore mask */
@@ -540,21 +548,33 @@ static acpi_status longhaul_walk_callback(acpi_handle obj_handle,
         return 1;
 }
 
+/* VIA don't support PM2 reg, but have something similar */
+static int enable_arbiter_disable(void)
+{
+        struct pci_dev *dev;
+        u8 pci_cmd;
+
+        /* Find PLE133 host bridge */
+        dev = pci_find_device(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8601_0, NULL);
+        if (dev != NULL) {
+                /* Enable access to port 0x22 */
+                pci_read_config_byte(dev, 0x78, &pci_cmd);
+                if ( !(pci_cmd & 1<<7) ) {
+                        pci_cmd |= 1<<7;
+                        pci_write_config_byte(dev, 0x78, pci_cmd);
+                }
+                return 1;
+        }
+        return 0;
+}
+
 static int __init longhaul_cpu_init(struct cpufreq_policy *policy)
 {
         struct cpuinfo_x86 *c = cpu_data;
         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->address == 0 || cx->latency > 1000) goto err_acpi;
-
-        /* Now check what we have on this motherboard */
+        /* Check what we have on this motherboard */
         switch (c->x86_model) {
         case 6:
                 cpu_model = CPU_SAMUEL;
@@ -636,6 +656,30 @@ static int __init longhaul_cpu_init(struct cpufreq_policy *policy)
                 break;
         };
 
+        /* Find ACPI data for processor */
+        acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT, ACPI_UINT32_MAX,
+                            &longhaul_walk_callback, NULL, (void *)&pr);
+        if (pr == NULL)
+                goto err_acpi;
+
+        if (longhaul_version == TYPE_POWERSAVER) {
+                /* Check ACPI support for C3 state */
+                cx = &pr->power.states[ACPI_STATE_C3];
+                if (cx->address == 0 ||
+                   (cx->latency > 1000 && ignore_latency == 0) )
+                        goto err_acpi;
+
+        } else {
+                /* Check ACPI support for bus master arbiter disable */
+                if (!pr->flags.bm_control) {
+                        if (!enable_arbiter_disable()) {
+                                printk(KERN_ERR PFX "No ACPI support. No VT8601 host bridge. Aborting.\n");
+                                return -ENODEV;
+                        } else
+                                port22_en = 1;
+                }
+        }
+
         ret = longhaul_get_ranges();
         if (ret != 0)
                 return ret;
@@ -731,6 +775,8 @@ static void __exit longhaul_exit(void)
 
 module_param (dont_scale_voltage, int, 0644);
 MODULE_PARM_DESC(dont_scale_voltage, "Don't scale voltage of processor");
+module_param(ignore_latency, int, 0644);
+MODULE_PARM_DESC(ignore_latency, "Skip ACPI C3 latency test");
 
 MODULE_AUTHOR ("Dave Jones <davej@codemonkey.org.uk>");
 MODULE_DESCRIPTION ("Longhaul driver for VIA Cyrix processors.");
@@ -738,4 +784,3 @@ MODULE_LICENSE ("GPL");
 
 late_initcall(longhaul_init);
 module_exit(longhaul_exit);
-