target/linux/brcm63xx/patches-3.8/024-MIPS-BCM63XX-rework-chip-detection.patch

   1 From 3f4570c9794fcae1cf62fbf3266a2e23edac67a5 Mon Sep 17 00:00:00 2001
   2 From: Jonas Gorski <jogo@openwrt.org>
   3 Date: Wed, 27 Jun 2012 15:01:09 +0200
   4 Subject: [PATCH 3/7] MIPS: BCM63XX: rework chip detection
   5
   6 Instead of trying to use a correlation of cpu prid and chip id and
   7 hoping they will always be unique, use the cpu prid to determine the
   8 chip id register location and just read out the chip id.
   9
  10 Signed-off-by: Jonas Gorski <jogo@openwrt.org>
  11 ---
  12  arch/mips/bcm63xx/cpu.c |   87 +++++++++++++++++++++++------------------------
  13  1 file changed, 42 insertions(+), 45 deletions(-)
  14
  15 --- a/arch/mips/bcm63xx/cpu.c
  16 +++ b/arch/mips/bcm63xx/cpu.c
  17 @@ -240,53 +240,27 @@ static unsigned int detect_memory_size(v
  18
  19  void __init bcm63xx_cpu_init(void)
  20  {
  21 -       unsigned int tmp, expected_cpu_id;
  22 +       unsigned int tmp;
  23         struct cpuinfo_mips *c = &current_cpu_data;
  24         unsigned int cpu = smp_processor_id();
  25 +       u32 chipid_reg;
  26
  27         /* soc registers location depends on cpu type */
  28 -       expected_cpu_id = 0;
  29 +       chipid_reg = 0;
  30
  31         switch (c->cputype) {
  32         case CPU_BMIPS3300:
  33 -               if ((read_c0_prid() & 0xff00) == PRID_IMP_BMIPS3300_ALT) {
  34 -                       expected_cpu_id = BCM6348_CPU_ID;
  35 -                       bcm63xx_regs_base = bcm6348_regs_base;
  36 -                       bcm63xx_irqs = bcm6348_irqs;
  37 -               } else {
  38 +               if ((read_c0_prid() & 0xff00) != PRID_IMP_BMIPS3300_ALT)
  39                         __cpu_name[cpu] = "Broadcom BCM6338";
  40 -                       expected_cpu_id = BCM6338_CPU_ID;
  41 -                       bcm63xx_regs_base = bcm6338_regs_base;
  42 -                       bcm63xx_irqs = bcm6338_irqs;
  43 -               }
  44 -               break;
  45 +               /* fall-through */
  46         case CPU_BMIPS32:
  47 -               expected_cpu_id = BCM6345_CPU_ID;
  48 -               bcm63xx_regs_base = bcm6345_regs_base;
  49 -               bcm63xx_irqs = bcm6345_irqs;
  50 +               chipid_reg = BCM_6345_PERF_BASE;
  51                 break;
  52         case CPU_BMIPS4350:
  53 -               if ((read_c0_prid() & 0xf0) == 0x10) {
  54 -                       expected_cpu_id = BCM6358_CPU_ID;
  55 -                       bcm63xx_regs_base = bcm6358_regs_base;
  56 -                       bcm63xx_irqs = bcm6358_irqs;
  57 -               } else {
  58 -                       /* all newer chips have the same chip id location */
  59 -                       u16 chip_id = bcm_readw(BCM_6368_PERF_BASE);
  60 -
  61 -                       switch (chip_id) {
  62 -                       case BCM6328_CPU_ID:
  63 -                               expected_cpu_id = BCM6328_CPU_ID;
  64 -                               bcm63xx_regs_base = bcm6328_regs_base;
  65 -                               bcm63xx_irqs = bcm6328_irqs;
  66 -                               break;
  67 -                       case BCM6368_CPU_ID:
  68 -                               expected_cpu_id = BCM6368_CPU_ID;
  69 -                               bcm63xx_regs_base = bcm6368_regs_base;
  70 -                               bcm63xx_irqs = bcm6368_irqs;
  71 -                               break;
  72 -                       }
  73 -               }
  74 +               if ((read_c0_prid() & 0xf0) == 0x10)
  75 +                       chipid_reg = BCM_6345_PERF_BASE;
  76 +               else
  77 +                       chipid_reg = BCM_6368_PERF_BASE;
  78                 break;
  79         }
  80
  81 @@ -294,20 +268,43 @@ void __init bcm63xx_cpu_init(void)
  82          * really early to panic, but delaying panic would not help since we
  83          * will never get any working console
  84          */
  85 -       if (!expected_cpu_id)
  86 +       if (!chipid_reg)
  87                 panic("unsupported Broadcom CPU");
  88
  89 -       /*
  90 -        * bcm63xx_regs_base is set, we can access soc registers
  91 -        */
  92 -
  93 -       /* double check CPU type */
  94 -       tmp = bcm_perf_readl(PERF_REV_REG);
  95 +       /* read out CPU type */
  96 +       tmp = bcm_readl(chipid_reg);
  97         bcm63xx_cpu_id = (tmp & REV_CHIPID_MASK) >> REV_CHIPID_SHIFT;
  98         bcm63xx_cpu_rev = (tmp & REV_REVID_MASK) >> REV_REVID_SHIFT;
  99
 100 -       if (bcm63xx_cpu_id != expected_cpu_id)
 101 -               panic("bcm63xx CPU id mismatch");
 102 +       switch (bcm63xx_cpu_id) {
 103 +       case BCM6328_CPU_ID:
 104 +               bcm63xx_regs_base = bcm6328_regs_base;
 105 +               bcm63xx_irqs = bcm6328_irqs;
 106 +               break;
 107 +       case BCM6338_CPU_ID:
 108 +               bcm63xx_regs_base = bcm6338_regs_base;
 109 +               bcm63xx_irqs = bcm6338_irqs;
 110 +               break;
 111 +       case BCM6345_CPU_ID:
 112 +               bcm63xx_regs_base = bcm6345_regs_base;
 113 +               bcm63xx_irqs = bcm6345_irqs;
 114 +               break;
 115 +       case BCM6348_CPU_ID:
 116 +               bcm63xx_regs_base = bcm6348_regs_base;
 117 +               bcm63xx_irqs = bcm6348_irqs;
 118 +               break;
 119 +       case BCM6358_CPU_ID:
 120 +               bcm63xx_regs_base = bcm6358_regs_base;
 121 +               bcm63xx_irqs = bcm6358_irqs;
 122 +               break;
 123 +       case BCM6368_CPU_ID:
 124 +               bcm63xx_regs_base = bcm6368_regs_base;
 125 +               bcm63xx_irqs = bcm6368_irqs;
 126 +               break;
 127 +       default:
 128 +               panic("unsupported broadcom CPU %x", bcm63xx_cpu_id);
 129 +               break;
 130 +       }
 131
 132         bcm63xx_cpu_freq = detect_cpu_clock();
 133         bcm63xx_memory_size = detect_memory_size();