target/linux/ipq806x/patches/0002-ARM-msm-Remove-pen_release-usage.patch

   1 From 18d53dfa103e63154fb8e548d55016d6ad210d28 Mon Sep 17 00:00:00 2001
   2 From: Rohit Vaswani <rvaswani@codeaurora.org>
   3 Date: Fri, 21 Jun 2013 12:17:37 -0700
   4 Subject: [PATCH 002/182] ARM: msm: Remove pen_release usage
   5
   6 pen_release is no longer required as the synchronization
   7 is now managed by generic arm code.
   8 This is done as suggested in https://lkml.org/lkml/2013/6/4/184
   9
  10 Cc: Russell King <linux@arm.linux.org.uk>
  11 Signed-off-by: Rohit Vaswani <rvaswani@codeaurora.org>
  12 Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
  13 Signed-off-by: Kumar Gala <galak@codeaurora.org>
  14 ---
  15  arch/arm/mach-msm/Makefile  |    2 +-
  16  arch/arm/mach-msm/headsmp.S |   39 ---------------------------------------
  17  arch/arm/mach-msm/hotplug.c |   31 ++++---------------------------
  18  arch/arm/mach-msm/platsmp.c |   37 +++----------------------------------
  19  4 files changed, 8 insertions(+), 101 deletions(-)
  20  delete mode 100644 arch/arm/mach-msm/headsmp.S
  21
  22 diff --git a/arch/arm/mach-msm/Makefile b/arch/arm/mach-msm/Makefile
  23 index 8e307a1..721f27f 100644
  24 --- a/arch/arm/mach-msm/Makefile
  25 +++ b/arch/arm/mach-msm/Makefile
  26 @@ -19,7 +19,7 @@ obj-$(CONFIG_MSM_SCM) += scm.o scm-boot.o
  27  CFLAGS_scm.o :=$(call as-instr,.arch_extension sec,-DREQUIRES_SEC=1)
  28
  29  obj-$(CONFIG_HOTPLUG_CPU) += hotplug.o
  30 -obj-$(CONFIG_SMP) += headsmp.o platsmp.o
  31 +obj-$(CONFIG_SMP) += platsmp.o
  32
  33  obj-$(CONFIG_MACH_TROUT) += board-trout.o board-trout-gpio.o board-trout-mmc.o devices-msm7x00.o
  34  obj-$(CONFIG_MACH_TROUT) += board-trout.o board-trout-gpio.o board-trout-mmc.o board-trout-panel.o devices-msm7x00.o
  35 diff --git a/arch/arm/mach-msm/headsmp.S b/arch/arm/mach-msm/headsmp.S
  36 deleted file mode 100644
  37 index 6c62c3f..0000000
  38 --- a/arch/arm/mach-msm/headsmp.S
  39 +++ /dev/null
  40 @@ -1,39 +0,0 @@
  41 -/*
  42 - *  linux/arch/arm/mach-realview/headsmp.S
  43 - *
  44 - *  Copyright (c) 2003 ARM Limited
  45 - *  All Rights Reserved
  46 - *
  47 - * This program is free software; you can redistribute it and/or modify
  48 - * it under the terms of the GNU General Public License version 2 as
  49 - * published by the Free Software Foundation.
  50 - */
  51 -#include <linux/linkage.h>
  52 -#include <linux/init.h>
  53 -
  54 -/*
  55 - * MSM specific entry point for secondary CPUs.  This provides
  56 - * a "holding pen" into which all secondary cores are held until we're
  57 - * ready for them to initialise.
  58 - */
  59 -ENTRY(msm_secondary_startup)
  60 -       mrc     p15, 0, r0, c0, c0, 5
  61 -       and     r0, r0, #15
  62 -       adr     r4, 1f
  63 -       ldmia   r4, {r5, r6}
  64 -       sub     r4, r4, r5
  65 -       add     r6, r6, r4
  66 -pen:   ldr     r7, [r6]
  67 -       cmp     r7, r0
  68 -       bne     pen
  69 -
  70 -       /*
  71 -        * we've been released from the holding pen: secondary_stack
  72 -        * should now contain the SVC stack for this core
  73 -        */
  74 -       b       secondary_startup
  75 -ENDPROC(msm_secondary_startup)
  76 -
  77 -       .align
  78 -1:     .long   .
  79 -       .long   pen_release
  80 diff --git a/arch/arm/mach-msm/hotplug.c b/arch/arm/mach-msm/hotplug.c
  81 index 326a872..cea80fc 100644
  82 --- a/arch/arm/mach-msm/hotplug.c
  83 +++ b/arch/arm/mach-msm/hotplug.c
  84 @@ -24,33 +24,10 @@ static inline void cpu_leave_lowpower(void)
  85
  86  static inline void platform_do_lowpower(unsigned int cpu)
  87  {
  88 -       /* Just enter wfi for now. TODO: Properly shut off the cpu. */
  89 -       for (;;) {
  90 -               /*
  91 -                * here's the WFI
  92 -                */
  93 -               asm("wfi"
  94 -                   :
  95 -                   :
  96 -                   : "memory", "cc");
  97 -
  98 -               if (pen_release == cpu_logical_map(cpu)) {
  99 -                       /*
 100 -                        * OK, proper wakeup, we're done
 101 -                        */
 102 -                       break;
 103 -               }
 104 -
 105 -               /*
 106 -                * getting here, means that we have come out of WFI without
 107 -                * having been woken up - this shouldn't happen
 108 -                *
 109 -                * The trouble is, letting people know about this is not really
 110 -                * possible, since we are currently running incoherently, and
 111 -                * therefore cannot safely call printk() or anything else
 112 -                */
 113 -               pr_debug("CPU%u: spurious wakeup call\n", cpu);
 114 -       }
 115 +       asm("wfi"
 116 +           :
 117 +           :
 118 +           : "memory", "cc");
 119  }
 120
 121  /*
 122 diff --git a/arch/arm/mach-msm/platsmp.c b/arch/arm/mach-msm/platsmp.c
 123 index f10a1f5..3721b31 100644
 124 --- a/arch/arm/mach-msm/platsmp.c
 125 +++ b/arch/arm/mach-msm/platsmp.c
 126 @@ -12,13 +12,10 @@
 127  #include <linux/errno.h>
 128  #include <linux/delay.h>
 129  #include <linux/device.h>
 130 -#include <linux/jiffies.h>
 131  #include <linux/smp.h>
 132  #include <linux/io.h>
 133
 134 -#include <asm/cacheflush.h>
 135  #include <asm/cputype.h>
 136 -#include <asm/mach-types.h>
 137  #include <asm/smp_plat.h>
 138
 139  #include "scm-boot.h"
 140 @@ -28,7 +25,7 @@
 141  #define SCSS_CPU1CORE_RESET 0xD80
 142  #define SCSS_DBG_STATUS_CORE_PWRDUP 0xE64
 143
 144 -extern void msm_secondary_startup(void);
 145 +extern void secondary_startup(void);
 146
 147  static DEFINE_SPINLOCK(boot_lock);
 148
 149 @@ -41,13 +38,6 @@ static inline int get_core_count(void)
 150  static void msm_secondary_init(unsigned int cpu)
 151  {
 152         /*
 153 -        * let the primary processor know we're out of the
 154 -        * pen, then head off into the C entry point
 155 -        */
 156 -       pen_release = -1;
 157 -       smp_wmb();
 158 -
 159 -       /*
 160          * Synchronise with the boot thread.
 161          */
 162         spin_lock(&boot_lock);
 163 @@ -57,7 +47,7 @@ static void msm_secondary_init(unsigned int cpu)
 164  static void prepare_cold_cpu(unsigned int cpu)
 165  {
 166         int ret;
 167 -       ret = scm_set_boot_addr(virt_to_phys(msm_secondary_startup),
 168 +       ret = scm_set_boot_addr(virt_to_phys(secondary_startup),
 169                                 SCM_FLAG_COLDBOOT_CPU1);
 170         if (ret == 0) {
 171                 void __iomem *sc1_base_ptr;
 172 @@ -75,7 +65,6 @@ static void prepare_cold_cpu(unsigned int cpu)
 173
 174  static int msm_boot_secondary(unsigned int cpu, struct task_struct *idle)
 175  {
 176 -       unsigned long timeout;
 177         static int cold_boot_done;
 178
 179         /* Only need to bring cpu out of reset this way once */
 180 @@ -91,39 +80,19 @@ static int msm_boot_secondary(unsigned int cpu, struct task_struct *idle)
 181         spin_lock(&boot_lock);
 182
 183         /*
 184 -        * The secondary processor is waiting to be released from
 185 -        * the holding pen - release it, then wait for it to flag
 186 -        * that it has been released by resetting pen_release.
 187 -        *
 188 -        * Note that "pen_release" is the hardware CPU ID, whereas
 189 -        * "cpu" is Linux's internal ID.
 190 -        */
 191 -       pen_release = cpu_logical_map(cpu);
 192 -       sync_cache_w(&pen_release);
 193 -
 194 -       /*
 195          * Send the secondary CPU a soft interrupt, thereby causing
 196          * the boot monitor to read the system wide flags register,
 197          * and branch to the address found there.
 198          */
 199         arch_send_wakeup_ipi_mask(cpumask_of(cpu));
 200
 201 -       timeout = jiffies + (1 * HZ);
 202 -       while (time_before(jiffies, timeout)) {
 203 -               smp_rmb();
 204 -               if (pen_release == -1)
 205 -                       break;
 206 -
 207 -               udelay(10);
 208 -       }
 209 -
 210         /*
 211          * now the secondary core is starting up let it run its
 212          * calibrations, then wait for it to finish
 213          */
 214         spin_unlock(&boot_lock);
 215
 216 -       return pen_release != -1 ? -ENOSYS : 0;
 217 +       return 0;
 218  }
 219
 220  /*
 221 --
 222 1.7.10.4
 223