Bug 201434 - [PATCH] Bad management of PSR_A bit
Summary: [PATCH] Bad management of PSR_A bit
Status: Closed FIXED
Alias: None
Product: Base System
Classification: Unclassified
Component: arm (show other bugs)
Version: CURRENT
Hardware: arm Any
: --- Affects Some People
Assignee: freebsd-arm (Nobody)
URL:
Keywords: patch
Depends on:
Blocks:
 
Reported: 2015-07-09 07:30 UTC by Grégory Soutadé
Modified: 2015-11-28 14:29 UTC (History)
1 user (show)

See Also:

Attachments
Clear PSR_A bit at startup (initarm) (728 bytes, patch)
2015-07-09 07:30 UTC, Grégory Soutadé 		no flags Details | Diff
View All Add an attachment (proposed patch, testcase, etc.)

Note You need to log in before you can comment on or make changes to this bug.
Description Grégory Soutadé 2015-07-09 07:30:36 UTC 
Created attachment 158557 [details]
Clear PSR_A bit at startup (initarm)

Sometimes at reboot, the PSR_A bit (CPSR register) is set. This bit mask further hardware bad accesses until it's cleared (going into userspace for me) leaving "Asynchronous External Abort" very late.

In the ARM_NEW_PMAP code, we call enable_interrupts() in initarm() to force clearing this bit. Nevertheless, enable_interrupts() does a mask with ARM_CPSR_I32 and ARM_CPSR_F32 bits making the call useless.

The attached patch correct it in ARM_NEW_PMAP and non ARM_NEW_PMAP code.
Comment 1 commit-hook freebsd_committer freebsd_triage 2015-11-10 13:47:35 UTC 
A commit references this bug:

Author: mmel
Date: Tue Nov 10 13:47:28 UTC 2015
New revision: 290661
URL: https://svnweb.freebsd.org/changeset/base/290661

Log:
  ARM: Refactor interrupt_enable/disable/restore.
  Allow manipulation with PSR_A bit on ARMv6+.
  Remove declaration of unused functions.

  This effectively enables asynchronous aborts on early bootstrap stage,
  which previously was not enabled due to an error in enable_interrupts().

  PR:		201434
  Reported by:	Gregory Soutade <soutade at gmail.com>
  Approved by:	kib (mentor)

Changes:
  head/sys/arm/include/cpufunc.h
Comment 2 Michael Moll freebsd_committer freebsd_triage 2015-11-28 14:29:55 UTC 
closing with mmel@'s blessings.