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authorRalf Baechle <ralf@linux-mips.org>2000-07-15 03:32:22 +0000
committerRalf Baechle <ralf@linux-mips.org>2000-07-15 03:32:22 +0000
commitf1da2c3860e301527d56a1ef0b56c649ee7c4b1b (patch)
tree562b5d2e8b9cb62eb983d78ff6bcf9789e08fcf6 /drivers/acpi/cpu.c
parent00f11569ac8ca73cbcdef8822de1583e79aee571 (diff)
Merge with Linux 2.4.0-test5-pre1. This works again on Origin UP.
The IP22 cache bugs which are plaguing some machines are still unfixed.
Diffstat (limited to 'drivers/acpi/cpu.c')
-rw-r--r--drivers/acpi/cpu.c307
1 files changed, 307 insertions, 0 deletions
diff --git a/drivers/acpi/cpu.c b/drivers/acpi/cpu.c
new file mode 100644
index 000000000..f1feeb12b
--- /dev/null
+++ b/drivers/acpi/cpu.c
@@ -0,0 +1,307 @@
+/*
+ * cpu.c - Processor handling
+ *
+ * Copyright (C) 2000 Andrew Henroid
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/pm.h>
+#include <linux/acpi.h>
+#include "acpi.h"
+#include "driver.h"
+
+unsigned long acpi_c2_exit_latency = ACPI_INFINITE;
+unsigned long acpi_c3_exit_latency = ACPI_INFINITE;
+unsigned long acpi_c2_enter_latency = ACPI_INFINITE;
+unsigned long acpi_c3_enter_latency = ACPI_INFINITE;
+
+static unsigned long acpi_pblk = ACPI_INVALID;
+static int acpi_c2_tested = 0;
+static int acpi_c3_tested = 0;
+
+/*
+ * Clear busmaster activity flag
+ */
+static inline void
+acpi_clear_bm_activity(struct acpi_facp *facp)
+{
+ acpi_write_pm1_status(facp, ACPI_BM);
+}
+
+/*
+ * Returns 1 if there has been busmaster activity
+ */
+static inline int
+acpi_bm_activity(struct acpi_facp *facp)
+{
+ return acpi_read_pm1_status(facp) & ACPI_BM;
+}
+
+/*
+ * Set system to sleep through busmaster requests
+ */
+static void
+acpi_sleep_on_busmaster(struct acpi_facp *facp)
+{
+ u32 pm1_cntr = acpi_read_pm1_control(facp);
+ if (pm1_cntr & ACPI_BM_RLD) {
+ pm1_cntr &= ~ACPI_BM_RLD;
+ acpi_write_pm1_control(facp, pm1_cntr);
+ }
+}
+
+/*
+ * Set system to wake on busmaster requests
+ */
+static void
+acpi_wake_on_busmaster(struct acpi_facp *facp)
+{
+ u32 pm1_cntr = acpi_read_pm1_control(facp);
+ if (!(pm1_cntr & ACPI_BM_RLD)) {
+ pm1_cntr |= ACPI_BM_RLD;
+ acpi_write_pm1_control(facp, pm1_cntr);
+ }
+ acpi_clear_bm_activity(facp);
+}
+
+/* The ACPI timer is just the low 24 bits */
+#define TIME_BEGIN(tmr) inl(tmr)
+#define TIME_END(tmr, begin) ((inl(tmr) - (begin)) & 0x00ffffff)
+
+/*
+ * Idle loop (uniprocessor only)
+ */
+static void
+acpi_idle(void)
+{
+ static int sleep_level = 1;
+ struct acpi_facp *facp = &acpi_facp;
+
+ if (!facp
+ || facp->hdr.signature != ACPI_FACP_SIG
+ || !facp->pm_tmr
+ || !acpi_pblk)
+ goto not_initialized;
+
+ /*
+ * start from the previous sleep level..
+ */
+ if (sleep_level == 1)
+ goto sleep1;
+ if (sleep_level == 2)
+ goto sleep2;
+ sleep3:
+ sleep_level = 3;
+ if (!acpi_c3_tested) {
+ printk(KERN_DEBUG "ACPI C3 works\n");
+ acpi_c3_tested = 1;
+ }
+ acpi_wake_on_busmaster(facp);
+ if (facp->pm2_cnt)
+ goto sleep3_with_arbiter;
+
+ for (;;) {
+ unsigned long time;
+ unsigned int pm_tmr = facp->pm_tmr;
+
+ __cli();
+ if (current->need_resched)
+ goto out;
+ if (acpi_bm_activity(facp))
+ goto sleep2;
+
+ time = TIME_BEGIN(pm_tmr);
+ inb(acpi_pblk + ACPI_P_LVL3);
+ /* Dummy read, force synchronization with the PMU */
+ inl(pm_tmr);
+ time = TIME_END(pm_tmr, time);
+
+ __sti();
+ if (time < acpi_c3_exit_latency)
+ goto sleep2;
+ }
+
+ sleep3_with_arbiter:
+ for (;;) {
+ unsigned long time;
+ u8 arbiter;
+ unsigned int pm2_cntr = facp->pm2_cnt;
+ unsigned int pm_tmr = facp->pm_tmr;
+
+ __cli();
+ if (current->need_resched)
+ goto out;
+ if (acpi_bm_activity(facp))
+ goto sleep2;
+
+ time = TIME_BEGIN(pm_tmr);
+ arbiter = inb(pm2_cntr) & ~ACPI_ARB_DIS;
+ /* Disable arbiter, park on CPU */
+ outb(arbiter | ACPI_ARB_DIS, pm2_cntr);
+ inb(acpi_pblk + ACPI_P_LVL3);
+ /* Dummy read, force synchronization with the PMU */
+ inl(pm_tmr);
+ time = TIME_END(pm_tmr, time);
+ /* Enable arbiter again.. */
+ outb(arbiter, pm2_cntr);
+
+ __sti();
+ if (time < acpi_c3_exit_latency)
+ goto sleep2;
+ }
+
+ sleep2:
+ sleep_level = 2;
+ if (!acpi_c2_tested) {
+ printk(KERN_DEBUG "ACPI C2 works\n");
+ acpi_c2_tested = 1;
+ }
+ acpi_wake_on_busmaster(facp); /* Required to track BM activity.. */
+ for (;;) {
+ unsigned long time;
+ unsigned int pm_tmr = facp->pm_tmr;
+
+ __cli();
+ if (current->need_resched)
+ goto out;
+
+ time = TIME_BEGIN(pm_tmr);
+ inb(acpi_pblk + ACPI_P_LVL2);
+ /* Dummy read, force synchronization with the PMU */
+ inl(pm_tmr);
+ time = TIME_END(pm_tmr, time);
+
+ __sti();
+ if (time < acpi_c2_exit_latency)
+ goto sleep1;
+ if (acpi_bm_activity(facp)) {
+ acpi_clear_bm_activity(facp);
+ continue;
+ }
+ if (time > acpi_c3_enter_latency)
+ goto sleep3;
+ }
+
+ sleep1:
+ sleep_level = 1;
+ acpi_sleep_on_busmaster(facp);
+ for (;;) {
+ unsigned long time;
+ unsigned int pm_tmr = facp->pm_tmr;
+
+ __cli();
+ if (current->need_resched)
+ goto out;
+ time = TIME_BEGIN(pm_tmr);
+ safe_halt();
+ time = TIME_END(pm_tmr, time);
+ if (time > acpi_c2_enter_latency)
+ goto sleep2;
+ }
+
+ not_initialized:
+ for (;;) {
+ __cli();
+ if (current->need_resched)
+ goto out;
+ safe_halt();
+ }
+
+ out:
+ __sti();
+}
+
+/*
+ * Get processor information
+ */
+static ACPI_STATUS
+acpi_find_cpu(ACPI_HANDLE handle, u32 level, void *ctx, void **value)
+{
+ ACPI_OBJECT obj;
+ ACPI_CX_STATE lat[4];
+ ACPI_CPU_THROTTLING_STATE throttle[ACPI_MAX_THROTTLE];
+ ACPI_BUFFER buf;
+ int i, count;
+
+ buf.length = sizeof(obj);
+ buf.pointer = &obj;
+ if (!ACPI_SUCCESS(acpi_evaluate_object(handle, NULL, NULL, &buf)))
+ return AE_OK;
+
+ printk(KERN_INFO "ACPI: PBLK %d @ 0x%04x:%d\n",
+ obj.processor.proc_id,
+ obj.processor.pblk_address,
+ obj.processor.pblk_length);
+ if (acpi_pblk != ACPI_INVALID
+ || !obj.processor.pblk_address
+ || obj.processor.pblk_length != 6)
+ return AE_OK;
+
+ acpi_pblk = obj.processor.pblk_address;
+
+ buf.length = sizeof(lat);
+ buf.pointer = lat;
+ if (!ACPI_SUCCESS(acpi_get_processor_cx_info(handle, &buf)))
+ return AE_OK;
+
+ if (lat[2].latency < MAX_CX_STATE_LATENCY) {
+ printk(KERN_INFO "ACPI: C2 supported\n");
+ acpi_c2_exit_latency = lat[2].latency;
+ }
+ if (lat[3].latency < MAX_CX_STATE_LATENCY) {
+ printk(KERN_INFO "ACPI: C3 supported\n");
+ acpi_c3_exit_latency = lat[3].latency;
+ }
+
+ memset(throttle, 0, sizeof(throttle));
+ buf.length = sizeof(throttle);
+ buf.pointer = throttle;
+
+ if (!ACPI_SUCCESS(acpi_get_processor_throttling_info(handle, &buf)))
+ return AE_OK;
+
+ for (i = 0, count = 0; i < ACPI_MAX_THROTTLE; i++) {
+ if (throttle[i].percent_of_clock)
+ count++;
+ }
+ count--;
+ if (count > 0)
+ printk(KERN_INFO "ACPI: %d throttling states\n", count);
+
+ return AE_OK;
+}
+
+int
+acpi_cpu_init(void)
+{
+ acpi_walk_namespace(ACPI_TYPE_PROCESSOR,
+ ACPI_ROOT_OBJECT,
+ ACPI_INT32_MAX,
+ acpi_find_cpu,
+ NULL,
+ NULL);
+
+#ifdef CONFIG_SMP
+ if (smp_num_cpus == 1)
+ pm_idle = acpi_idle;
+#else
+ pm_idle = acpi_idle;
+#endif
+
+ return 0;
+}