ARCv2: Add explcit unaligned access support (and ability to disable too)

As of today we enable unaligned access unconditionally on ARCv2.
Do this under a Kconfig option to allow disable it for test, benchmarking
etc. Also while at it

  - Select HAVE_EFFICIENT_UNALIGNED_ACCESS
  - Although gcc defaults to unaligned access (since GNU 2018.03), add the
    right toggles for enabling or disabling as appropriate
  - update bootlog to prints both HW feature status (exists, enabled/disabled)
    and SW status (used / not used).
  - wire up the relaxed memcpy for unaligned access

Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
[vgupta: squashed patches, handle gcc -mno-unaligned-access quick]
This commit is contained in:
Eugeniy Paltsev
2019-01-30 19:32:41 +03:00
committed by Vineet Gupta
parent 4d1e7918aa
commit 7655146883
9 changed files with 57 additions and 14 deletions

View File

@@ -82,6 +82,7 @@
#define ECR_V_DTLB_MISS 0x05
#define ECR_V_PROTV 0x06
#define ECR_V_TRAP 0x09
#define ECR_V_MISALIGN 0x0d
#endif
/* DTLB Miss and Protection Violation Cause Codes */

View File

@@ -44,7 +44,13 @@
#define ARCV2_IRQ_DEF_PRIO 1
/* seed value for status register */
#define ISA_INIT_STATUS_BITS (STATUS_IE_MASK | STATUS_AD_MASK | \
#ifdef CONFIG_ARC_USE_UNALIGNED_MEM_ACCESS
#define __AD_ENB STATUS_AD_MASK
#else
#define __AD_ENB 0
#endif
#define ISA_INIT_STATUS_BITS (STATUS_IE_MASK | __AD_ENB | \
(ARCV2_IRQ_DEF_PRIO << 1))
#ifndef __ASSEMBLY__