patch-2.4.0-test4 linux/drivers/acpi/cpu.c

• Lines: 308
• Date: Wed Jul 12 13:21:57 2000
• Orig file: v2.4.0-test3/linux/drivers/acpi/cpu.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.4.0-test3/linux/drivers/acpi/cpu.c linux/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;
+}