git.ipfire.org Git - thirdparty/kernel/stable-queue.git/blob

   1 From 8e3ed9e786511ad800c33605ed904b9de49323cf Mon Sep 17 00:00:00 2001
   2 From: Chandrakanth patil <chandrakanth.patil@broadcom.com>
   3 Date: Tue, 3 Oct 2023 16:30:18 +0530
   4 Subject: scsi: megaraid_sas: Increase register read retry rount from 3 to 30 for selected registers
   5
   6 From: Chandrakanth patil <chandrakanth.patil@broadcom.com>
   7
   8 commit 8e3ed9e786511ad800c33605ed904b9de49323cf upstream.
   9
  10 In BMC environments with concurrent access to multiple registers, certain
  11 registers occasionally yield a value of 0 even after 3 retries due to
  12 hardware errata. As a fix, we have extended the retry count from 3 to 30.
  13
  14 The same errata applies to the mpt3sas driver, and a similar patch has
  15 been accepted. Please find more details in the mpt3sas patch reference
  16 link.
  17
  18 Link: https://lore.kernel.org/r/20230829090020.5417-2-ranjan.kumar@broadcom.com
  19 Fixes: 272652fcbf1a ("scsi: megaraid_sas: add retry logic in megasas_readl")
  20 Cc: stable@vger.kernel.org
  21 Signed-off-by: Chandrakanth patil <chandrakanth.patil@broadcom.com>
  22 Signed-off-by: Sumit Saxena <sumit.saxena@broadcom.com>
  23 Link: https://lore.kernel.org/r/20231003110021.168862-2-chandrakanth.patil@broadcom.com
  24 Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
  25 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  26 ---
  27  drivers/scsi/megaraid/megaraid_sas_base.c |    4 ++--
  28  1 file changed, 2 insertions(+), 2 deletions(-)
  29
  30 --- a/drivers/scsi/megaraid/megaraid_sas_base.c
  31 +++ b/drivers/scsi/megaraid/megaraid_sas_base.c
  32 @@ -248,13 +248,13 @@ u32 megasas_readl(struct megasas_instanc
  33          * Fusion registers could intermittently return all zeroes.
  34          * This behavior is transient in nature and subsequent reads will
  35          * return valid value. As a workaround in driver, retry readl for
  36 -        * upto three times until a non-zero value is read.
  37 +        * up to thirty times until a non-zero value is read.
  38          */
  39         if (instance->adapter_type == AERO_SERIES) {
  40                 do {
  41                         ret_val = readl(addr);
  42                         i++;
  43 -               } while (ret_val == 0 && i < 3);
  44 +               } while (ret_val == 0 && i < 30);
  45                 return ret_val;
  46         } else {
  47                 return readl(addr);