target/linux/brcm47xx/patches-3.14/153-MIPS-BCM47XX-Detect-more-then-128-MiB-of-RAM-HIGHMEM.patch

   1 From 6ee1d93455384cef8a0426effe85da241b525b63 Mon Sep 17 00:00:00 2001
   2 From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <zajec5@gmail.com>
   3 Date: Thu, 17 Jul 2014 23:26:33 +0200
   4 Subject: [PATCH 153/153] MIPS: BCM47XX: Detect more then 128 MiB of RAM
   5  (HIGHMEM)
   6 MIME-Version: 1.0
   7 Content-Type: text/plain; charset=UTF-8
   8 Content-Transfer-Encoding: 8bit
   9
  10 So far BCM47XX can only detect amount of HIGHMEM. It still requires
  11 adding (registering) and well-testing before enabling by default.
  12
  13 Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
  14 Acked-by: Hauke Mehrtens <hauke@hauke-m.de>
  15 Cc: linux-mips@linux-mips.org
  16 Patchwork: https://patchwork.linux-mips.org/patch/7396/
  17 Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
  18 ---
  19  arch/mips/bcm47xx/bcm47xx_private.h |  3 ++
  20  arch/mips/bcm47xx/prom.c            | 68 ++++++++++++++++++++++++++++++++++++-
  21  arch/mips/bcm47xx/setup.c           |  3 ++
  22  arch/mips/include/asm/pgtable-32.h  |  2 ++
  23  arch/mips/mm/tlb-r4k.c              |  2 +-
  24  5 files changed, 76 insertions(+), 2 deletions(-)
  25
  26 --- a/arch/mips/bcm47xx/bcm47xx_private.h
  27 +++ b/arch/mips/bcm47xx/bcm47xx_private.h
  28 @@ -3,6 +3,9 @@
  29
  30  #include <linux/kernel.h>
  31
  32 +/* prom.c */
  33 +void __init bcm47xx_prom_highmem_init(void);
  34 +
  35  /* buttons.c */
  36  int __init bcm47xx_buttons_register(void);
  37
  38 --- a/arch/mips/bcm47xx/prom.c
  39 +++ b/arch/mips/bcm47xx/prom.c
  40 @@ -51,6 +51,8 @@ __init void bcm47xx_set_system_type(u16
  41                  chip_id);
  42  }
  43
  44 +static unsigned long lowmem __initdata;
  45 +
  46  static __init void prom_init_mem(void)
  47  {
  48         unsigned long mem;
  49 @@ -84,6 +86,7 @@ static __init void prom_init_mem(void)
  50                 if (!memcmp(prom_init, prom_init + mem, 32))
  51                         break;
  52         }
  53 +       lowmem = mem;
  54
  55         /* Ignoring the last page when ddr size is 128M. Cached
  56          * accesses to last page is causing the processor to prefetch
  57 @@ -92,7 +95,6 @@ static __init void prom_init_mem(void)
  58          */
  59         if (c->cputype == CPU_74K && (mem == (128  << 20)))
  60                 mem -= 0x1000;
  61 -
  62         add_memory_region(0, mem, BOOT_MEM_RAM);
  63  }
  64
  65 @@ -111,3 +113,67 @@ void __init prom_init(void)
  66  void __init prom_free_prom_memory(void)
  67  {
  68  }
  69 +
  70 +#if defined(CONFIG_BCM47XX_BCMA) && defined(CONFIG_HIGHMEM)
  71 +
  72 +#define EXTVBASE       0xc0000000
  73 +#define ENTRYLO(x)     ((pte_val(pfn_pte((x) >> _PFN_SHIFT, PAGE_KERNEL_UNCACHED)) >> 6) | 1)
  74 +
  75 +#include <asm/tlbflush.h>
  76 +
  77 +/* Stripped version of tlb_init, with the call to build_tlb_refill_handler
  78 + * dropped. Calling it at this stage causes a hang.
  79 + */
  80 +void __cpuinit early_tlb_init(void)
  81 +{
  82 +       write_c0_pagemask(PM_DEFAULT_MASK);
  83 +       write_c0_wired(0);
  84 +       temp_tlb_entry = current_cpu_data.tlbsize - 1;
  85 +       local_flush_tlb_all();
  86 +}
  87 +
  88 +void __init bcm47xx_prom_highmem_init(void)
  89 +{
  90 +       unsigned long off = (unsigned long)prom_init;
  91 +       unsigned long extmem = 0;
  92 +       bool highmem_region = false;
  93 +
  94 +       if (WARN_ON(bcm47xx_bus_type != BCM47XX_BUS_TYPE_BCMA))
  95 +               return;
  96 +
  97 +       if (bcm47xx_bus.bcma.bus.chipinfo.id == BCMA_CHIP_ID_BCM4706)
  98 +               highmem_region = true;
  99 +
 100 +       if (lowmem != 128 << 20 || !highmem_region)
 101 +               return;
 102 +
 103 +       early_tlb_init();
 104 +
 105 +       /* Add one temporary TLB entry to map SDRAM Region 2.
 106 +        *      Physical        Virtual
 107 +        *      0x80000000      0xc0000000      (1st: 256MB)
 108 +        *      0x90000000      0xd0000000      (2nd: 256MB)
 109 +        */
 110 +       add_temporary_entry(ENTRYLO(0x80000000),
 111 +                           ENTRYLO(0x80000000 + (256 << 20)),
 112 +                           EXTVBASE, PM_256M);
 113 +
 114 +       off = EXTVBASE + __pa(off);
 115 +       for (extmem = 128 << 20; extmem < 512 << 20; extmem <<= 1) {
 116 +               if (!memcmp(prom_init, (void *)(off + extmem), 16))
 117 +                       break;
 118 +       }
 119 +       extmem -= lowmem;
 120 +
 121 +       early_tlb_init();
 122 +
 123 +       if (!extmem)
 124 +               return;
 125 +
 126 +       pr_warn("Found %lu MiB of extra memory, but highmem is unsupported yet!\n",
 127 +               extmem >> 20);
 128 +
 129 +       /* TODO: Register extra memory */
 130 +}
 131 +
 132 +#endif /* defined(CONFIG_BCM47XX_BCMA) && defined(CONFIG_HIGHMEM) */
 133 --- a/arch/mips/bcm47xx/setup.c
 134 +++ b/arch/mips/bcm47xx/setup.c
 135 @@ -231,6 +231,9 @@ void __init plat_mem_setup(void)
 136                 bcm47xx_bus_type = BCM47XX_BUS_TYPE_BCMA;
 137                 bcm47xx_register_bcma();
 138                 bcm47xx_set_system_type(bcm47xx_bus.bcma.bus.chipinfo.id);
 139 +#ifdef CONFIG_HIGHMEM
 140 +               bcm47xx_prom_highmem_init();
 141 +#endif
 142  #endif
 143         } else {
 144                 printk(KERN_INFO "bcm47xx: using ssb bus\n");
 145 --- a/arch/mips/include/asm/pgtable-32.h
 146 +++ b/arch/mips/include/asm/pgtable-32.h
 147 @@ -18,6 +18,8 @@
 148
 149  #include <asm-generic/pgtable-nopmd.h>
 150
 151 +extern int temp_tlb_entry __cpuinitdata;
 152 +
 153  /*
 154   * - add_temporary_entry() add a temporary TLB entry. We use TLB entries
 155   *     starting at the top and working down. This is for populating the
 156 --- a/arch/mips/mm/tlb-r4k.c
 157 +++ b/arch/mips/mm/tlb-r4k.c
 158 @@ -417,7 +417,7 @@ int __init has_transparent_hugepage(void
 159   * lifetime of the system
 160   */
 161
 162 -static int temp_tlb_entry __cpuinitdata;
 163 +int temp_tlb_entry __cpuinitdata;
 164
 165  __init int add_temporary_entry(unsigned long entrylo0, unsigned long entrylo1,
 166                                unsigned long entryhi, unsigned long pagemask)