target/linux/bcm53xx/patches-4.4/301-Revert-ARM-BCM5301X-remove-workaround-imprecise-abor.patch

   1 From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <zajec5@gmail.com>
   2 Date: Tue, 8 Mar 2016 09:03:21 +0100
   3 Subject: [PATCH] Revert "ARM: BCM5301X: remove workaround imprecise abort
   4  fault handler"
   5 MIME-Version: 1.0
   6 Content-Type: text/plain; charset=UTF-8
   7 Content-Transfer-Encoding: 8bit
   8
   9 This reverts commit 937b12306ea79044c86f2e69b3061c7279245825.
  10
  11 It seems imprecise external abort (0x1406) can be still happen on
  12 BCM4709 during PCI initialization.
  13
  14 Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
  15 ---
  16
  17 --- a/arch/arm/mach-bcm/bcm_5301x.c
  18 +++ b/arch/arm/mach-bcm/bcm_5301x.c
  19 @@ -9,6 +9,40 @@
  20  #include <asm/hardware/cache-l2x0.h>
  21
  22  #include <asm/mach/arch.h>
  23 +#include <asm/siginfo.h>
  24 +#include <asm/signal.h>
  25 +
  26 +
  27 +static bool first_fault = true;
  28 +
  29 +static int bcm5301x_abort_handler(unsigned long addr, unsigned int fsr,
  30 +                                struct pt_regs *regs)
  31 +{
  32 +       if ((fsr == 0x1406 || fsr == 0x1c06) && first_fault) {
  33 +               first_fault = false;
  34 +
  35 +               /*
  36 +                * These faults with codes 0x1406 (BCM4709) or 0x1c06 happens
  37 +                * for no good reason, possibly left over from the CFE boot
  38 +                * loader.
  39 +                */
  40 +               pr_warn("External imprecise Data abort at addr=%#lx, fsr=%#x ignored.\n",
  41 +                       addr, fsr);
  42 +
  43 +               /* Returning non-zero causes fault display and panic */
  44 +               return 0;
  45 +       }
  46 +
  47 +       /* Others should cause a fault */
  48 +       return 1;
  49 +}
  50 +
  51 +static void __init bcm5301x_init_early(void)
  52 +{
  53 +       /* Install our hook */
  54 +       hook_fault_code(16 + 6, bcm5301x_abort_handler, SIGBUS, BUS_OBJERR,
  55 +                       "imprecise external abort");
  56 +}
  57
  58  static const char *const bcm5301x_dt_compat[] __initconst = {
  59         "brcm,bcm4708",
  60 @@ -18,5 +52,6 @@ static const char *const bcm5301x_dt_com
  61  DT_MACHINE_START(BCM5301X, "BCM5301X")
  62         .l2c_aux_val    = 0,
  63         .l2c_aux_mask   = ~0,
  64 +       .init_early     = bcm5301x_init_early,
  65         .dt_compat      = bcm5301x_dt_compat,
  66  MACHINE_END