MIPS: Consolidate idle loop / WAIT instruction support in a single file.
authorRalf Baechle <ralf@linux-mips.org>
Tue, 21 May 2013 08:53:37 +0000 (10:53 +0200)
committerRalf Baechle <ralf@linux-mips.org>
Tue, 21 May 2013 23:34:25 +0000 (01:34 +0200)
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
arch/mips/kernel/Makefile
arch/mips/kernel/cpu-probe.c
arch/mips/kernel/idle.c [new file with mode: 0644]
arch/mips/kernel/process.c

index 6ad9e04bdf6210a8b722e92aca5e49161cb4deca..423d871a946ba15ae5b5ea70338530949fa8d166 100644 (file)
@@ -4,7 +4,7 @@
 
 extra-y                := head.o vmlinux.lds
 
-obj-y          += cpu-probe.o branch.o entry.o genex.o irq.o process.o \
+obj-y          += cpu-probe.o branch.o entry.o genex.o idle.o irq.o process.o \
                   prom.o ptrace.o reset.o setup.o signal.o syscall.o \
                   time.o topology.o traps.o unaligned.o watch.o vdso.o
 
index 4bbffdb9024ffb9cf437adb4fd5243e75e68a88c..c6568bf4b1b05559b43bc18f65e33c84a85963ba 100644 (file)
 #include <asm/spram.h>
 #include <asm/uaccess.h>
 
-/*
- * Not all of the MIPS CPUs have the "wait" instruction available. Moreover,
- * the implementation of the "wait" feature differs between CPU families. This
- * points to the function that implements CPU specific wait.
- * The wait instruction stops the pipeline and reduces the power consumption of
- * the CPU very much.
- */
-void (*cpu_wait)(void);
-EXPORT_SYMBOL(cpu_wait);
-
-static void r3081_wait(void)
-{
-       unsigned long cfg = read_c0_conf();
-       write_c0_conf(cfg | R30XX_CONF_HALT);
-}
-
-static void r39xx_wait(void)
-{
-       local_irq_disable();
-       if (!need_resched())
-               write_c0_conf(read_c0_conf() | TX39_CONF_HALT);
-       local_irq_enable();
-}
-
-extern void r4k_wait(void);
-
-/*
- * This variant is preferable as it allows testing need_resched and going to
- * sleep depending on the outcome atomically.  Unfortunately the "It is
- * implementation-dependent whether the pipeline restarts when a non-enabled
- * interrupt is requested" restriction in the MIPS32/MIPS64 architecture makes
- * using this version a gamble.
- */
-void r4k_wait_irqoff(void)
-{
-       local_irq_disable();
-       if (!need_resched())
-               __asm__("       .set    push            \n"
-                       "       .set    mips3           \n"
-                       "       wait                    \n"
-                       "       .set    pop             \n");
-       local_irq_enable();
-       __asm__("       .globl __pastwait       \n"
-               "__pastwait:                    \n");
-}
-
-/*
- * The RM7000 variant has to handle erratum 38.         The workaround is to not
- * have any pending stores when the WAIT instruction is executed.
- */
-static void rm7k_wait_irqoff(void)
-{
-       local_irq_disable();
-       if (!need_resched())
-               __asm__(
-               "       .set    push                                    \n"
-               "       .set    mips3                                   \n"
-               "       .set    noat                                    \n"
-               "       mfc0    $1, $12                                 \n"
-               "       sync                                            \n"
-               "       mtc0    $1, $12         # stalls until W stage  \n"
-               "       wait                                            \n"
-               "       mtc0    $1, $12         # stalls until W stage  \n"
-               "       .set    pop                                     \n");
-       local_irq_enable();
-}
-
-/*
- * The Au1xxx wait is available only if using 32khz counter or
- * external timer source, but specifically not CP0 Counter.
- * alchemy/common/time.c may override cpu_wait!
- */
-static void au1k_wait(void)
-{
-       __asm__("       .set    mips3                   \n"
-               "       cache   0x14, 0(%0)             \n"
-               "       cache   0x14, 32(%0)            \n"
-               "       sync                            \n"
-               "       nop                             \n"
-               "       wait                            \n"
-               "       nop                             \n"
-               "       nop                             \n"
-               "       nop                             \n"
-               "       nop                             \n"
-               "       .set    mips0                   \n"
-               : : "r" (au1k_wait));
-}
-
-static int __initdata nowait;
-
-static int __init wait_disable(char *s)
-{
-       nowait = 1;
-
-       return 1;
-}
-
-__setup("nowait", wait_disable);
-
 static int __cpuinitdata mips_fpu_disabled;
 
 static int __init fpu_disable(char *s)
@@ -150,105 +51,6 @@ static int __init dsp_disable(char *s)
 
 __setup("nodsp", dsp_disable);
 
-void __init check_wait(void)
-{
-       struct cpuinfo_mips *c = &current_cpu_data;
-
-       if (nowait) {
-               printk("Wait instruction disabled.\n");
-               return;
-       }
-
-       switch (c->cputype) {
-       case CPU_R3081:
-       case CPU_R3081E:
-               cpu_wait = r3081_wait;
-               break;
-       case CPU_TX3927:
-               cpu_wait = r39xx_wait;
-               break;
-       case CPU_R4200:
-/*     case CPU_R4300: */
-       case CPU_R4600:
-       case CPU_R4640:
-       case CPU_R4650:
-       case CPU_R4700:
-       case CPU_R5000:
-       case CPU_R5500:
-       case CPU_NEVADA:
-       case CPU_4KC:
-       case CPU_4KEC:
-       case CPU_4KSC:
-       case CPU_5KC:
-       case CPU_25KF:
-       case CPU_PR4450:
-       case CPU_BMIPS3300:
-       case CPU_BMIPS4350:
-       case CPU_BMIPS4380:
-       case CPU_BMIPS5000:
-       case CPU_CAVIUM_OCTEON:
-       case CPU_CAVIUM_OCTEON_PLUS:
-       case CPU_CAVIUM_OCTEON2:
-       case CPU_JZRISC:
-       case CPU_LOONGSON1:
-       case CPU_XLR:
-       case CPU_XLP:
-               cpu_wait = r4k_wait;
-               break;
-
-       case CPU_RM7000:
-               cpu_wait = rm7k_wait_irqoff;
-               break;
-
-       case CPU_M14KC:
-       case CPU_M14KEC:
-       case CPU_24K:
-       case CPU_34K:
-       case CPU_1004K:
-               cpu_wait = r4k_wait;
-               if (read_c0_config7() & MIPS_CONF7_WII)
-                       cpu_wait = r4k_wait_irqoff;
-               break;
-
-       case CPU_74K:
-               cpu_wait = r4k_wait;
-               if ((c->processor_id & 0xff) >= PRID_REV_ENCODE_332(2, 1, 0))
-                       cpu_wait = r4k_wait_irqoff;
-               break;
-
-       case CPU_TX49XX:
-               cpu_wait = r4k_wait_irqoff;
-               break;
-       case CPU_ALCHEMY:
-               cpu_wait = au1k_wait;
-               break;
-       case CPU_20KC:
-               /*
-                * WAIT on Rev1.0 has E1, E2, E3 and E16.
-                * WAIT on Rev2.0 and Rev3.0 has E16.
-                * Rev3.1 WAIT is nop, why bother
-                */
-               if ((c->processor_id & 0xff) <= 0x64)
-                       break;
-
-               /*
-                * Another rev is incremeting c0_count at a reduced clock
-                * rate while in WAIT mode.  So we basically have the choice
-                * between using the cp0 timer as clocksource or avoiding
-                * the WAIT instruction.  Until more details are known,
-                * disable the use of WAIT for 20Kc entirely.
-                  cpu_wait = r4k_wait;
-                */
-               break;
-       case CPU_RM9000:
-               if ((c->processor_id & 0x00ff) >= 0x40)
-                       cpu_wait = r4k_wait;
-               break;
-       default:
-               break;
-       }
-}
-
 static inline void check_errata(void)
 {
        struct cpuinfo_mips *c = &current_cpu_data;
diff --git a/arch/mips/kernel/idle.c b/arch/mips/kernel/idle.c
new file mode 100644 (file)
index 0000000..1e9d938
--- /dev/null
@@ -0,0 +1,232 @@
+/*
+ * MIPS idle loop and WAIT instruction support.
+ *
+ * Copyright (C) xxxx  the Anonymous
+ * Copyright (C) 1994 - 2006 Ralf Baechle
+ * Copyright (C) 2003, 2004  Maciej W. Rozycki
+ * Copyright (C) 2001, 2004, 2011, 2012         MIPS Technologies, Inc.
+ *
+ * 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.
+ */
+#include <linux/export.h>
+#include <linux/init.h>
+#include <linux/irqflags.h>
+#include <linux/printk.h>
+#include <linux/sched.h>
+#include <asm/cpu.h>
+#include <asm/cpu-info.h>
+#include <asm/mipsregs.h>
+
+/*
+ * Not all of the MIPS CPUs have the "wait" instruction available. Moreover,
+ * the implementation of the "wait" feature differs between CPU families. This
+ * points to the function that implements CPU specific wait.
+ * The wait instruction stops the pipeline and reduces the power consumption of
+ * the CPU very much.
+ */
+void (*cpu_wait)(void);
+EXPORT_SYMBOL(cpu_wait);
+
+static void r3081_wait(void)
+{
+       unsigned long cfg = read_c0_conf();
+       write_c0_conf(cfg | R30XX_CONF_HALT);
+}
+
+static void r39xx_wait(void)
+{
+       local_irq_disable();
+       if (!need_resched())
+               write_c0_conf(read_c0_conf() | TX39_CONF_HALT);
+       local_irq_enable();
+}
+
+extern void r4k_wait(void);
+
+/*
+ * This variant is preferable as it allows testing need_resched and going to
+ * sleep depending on the outcome atomically.  Unfortunately the "It is
+ * implementation-dependent whether the pipeline restarts when a non-enabled
+ * interrupt is requested" restriction in the MIPS32/MIPS64 architecture makes
+ * using this version a gamble.
+ */
+void r4k_wait_irqoff(void)
+{
+       local_irq_disable();
+       if (!need_resched())
+               __asm__("       .set    push            \n"
+                       "       .set    mips3           \n"
+                       "       wait                    \n"
+                       "       .set    pop             \n");
+       local_irq_enable();
+       __asm__("       .globl __pastwait       \n"
+               "__pastwait:                    \n");
+}
+
+/*
+ * The RM7000 variant has to handle erratum 38.         The workaround is to not
+ * have any pending stores when the WAIT instruction is executed.
+ */
+static void rm7k_wait_irqoff(void)
+{
+       local_irq_disable();
+       if (!need_resched())
+               __asm__(
+               "       .set    push                                    \n"
+               "       .set    mips3                                   \n"
+               "       .set    noat                                    \n"
+               "       mfc0    $1, $12                                 \n"
+               "       sync                                            \n"
+               "       mtc0    $1, $12         # stalls until W stage  \n"
+               "       wait                                            \n"
+               "       mtc0    $1, $12         # stalls until W stage  \n"
+               "       .set    pop                                     \n");
+       local_irq_enable();
+}
+
+/*
+ * The Au1xxx wait is available only if using 32khz counter or
+ * external timer source, but specifically not CP0 Counter.
+ * alchemy/common/time.c may override cpu_wait!
+ */
+static void au1k_wait(void)
+{
+       __asm__("       .set    mips3                   \n"
+               "       cache   0x14, 0(%0)             \n"
+               "       cache   0x14, 32(%0)            \n"
+               "       sync                            \n"
+               "       nop                             \n"
+               "       wait                            \n"
+               "       nop                             \n"
+               "       nop                             \n"
+               "       nop                             \n"
+               "       nop                             \n"
+               "       .set    mips0                   \n"
+               : : "r" (au1k_wait));
+}
+
+static int __initdata nowait;
+
+static int __init wait_disable(char *s)
+{
+       nowait = 1;
+
+       return 1;
+}
+
+__setup("nowait", wait_disable);
+
+void __init check_wait(void)
+{
+       struct cpuinfo_mips *c = &current_cpu_data;
+
+       if (nowait) {
+               printk("Wait instruction disabled.\n");
+               return;
+       }
+
+       switch (c->cputype) {
+       case CPU_R3081:
+       case CPU_R3081E:
+               cpu_wait = r3081_wait;
+               break;
+       case CPU_TX3927:
+               cpu_wait = r39xx_wait;
+               break;
+       case CPU_R4200:
+/*     case CPU_R4300: */
+       case CPU_R4600:
+       case CPU_R4640:
+       case CPU_R4650:
+       case CPU_R4700:
+       case CPU_R5000:
+       case CPU_R5500:
+       case CPU_NEVADA:
+       case CPU_4KC:
+       case CPU_4KEC:
+       case CPU_4KSC:
+       case CPU_5KC:
+       case CPU_25KF:
+       case CPU_PR4450:
+       case CPU_BMIPS3300:
+       case CPU_BMIPS4350:
+       case CPU_BMIPS4380:
+       case CPU_BMIPS5000:
+       case CPU_CAVIUM_OCTEON:
+       case CPU_CAVIUM_OCTEON_PLUS:
+       case CPU_CAVIUM_OCTEON2:
+       case CPU_JZRISC:
+       case CPU_LOONGSON1:
+       case CPU_XLR:
+       case CPU_XLP:
+               cpu_wait = r4k_wait;
+               break;
+
+       case CPU_RM7000:
+               cpu_wait = rm7k_wait_irqoff;
+               break;
+
+       case CPU_M14KC:
+       case CPU_M14KEC:
+       case CPU_24K:
+       case CPU_34K:
+       case CPU_1004K:
+               cpu_wait = r4k_wait;
+               if (read_c0_config7() & MIPS_CONF7_WII)
+                       cpu_wait = r4k_wait_irqoff;
+               break;
+
+       case CPU_74K:
+               cpu_wait = r4k_wait;
+               if ((c->processor_id & 0xff) >= PRID_REV_ENCODE_332(2, 1, 0))
+                       cpu_wait = r4k_wait_irqoff;
+               break;
+
+       case CPU_TX49XX:
+               cpu_wait = r4k_wait_irqoff;
+               break;
+       case CPU_ALCHEMY:
+               cpu_wait = au1k_wait;
+               break;
+       case CPU_20KC:
+               /*
+                * WAIT on Rev1.0 has E1, E2, E3 and E16.
+                * WAIT on Rev2.0 and Rev3.0 has E16.
+                * Rev3.1 WAIT is nop, why bother
+                */
+               if ((c->processor_id & 0xff) <= 0x64)
+                       break;
+
+               /*
+                * Another rev is incremeting c0_count at a reduced clock
+                * rate while in WAIT mode.  So we basically have the choice
+                * between using the cp0 timer as clocksource or avoiding
+                * the WAIT instruction.  Until more details are known,
+                * disable the use of WAIT for 20Kc entirely.
+                  cpu_wait = r4k_wait;
+                */
+               break;
+       case CPU_RM9000:
+               if ((c->processor_id & 0x00ff) >= 0x40)
+                       cpu_wait = r4k_wait;
+               break;
+       default:
+               break;
+       }
+}
+
+void arch_cpu_idle(void)
+{
+#ifdef CONFIG_MIPS_MT_SMTC
+       extern void smtc_idle_loop_hook(void);
+
+       smtc_idle_loop_hook();
+#endif
+       if (cpu_wait)
+               (*cpu_wait)();
+       else
+               local_irq_enable();
+}
index a682a87bcc043152bb741623d196032e444e81d1..c6a041d9d05d57fcd71f91a228c86524e00efd08 100644 (file)
@@ -51,19 +51,6 @@ void arch_cpu_idle_dead(void)
 }
 #endif
 
-void arch_cpu_idle(void)
-{
-#ifdef CONFIG_MIPS_MT_SMTC
-       extern void smtc_idle_loop_hook(void);
-
-       smtc_idle_loop_hook();
-#endif
-       if (cpu_wait)
-               (*cpu_wait)();
-       else
-               local_irq_enable();
-}
-
 asmlinkage void ret_from_fork(void);
 asmlinkage void ret_from_kernel_thread(void);