Skip to content

Commit

Permalink
ARMv7: Mark the PTWs inner WBWA on SMP and WB on UP
Browse files Browse the repository at this point in the history
There are additional bits to set for the ARMv7 SMP extensions in the
TTBR registers. The IRGN bits order is counter-intuitive but it allows
software built for the ARMv7 base architecture to run on an
implementation with the MP extensions.

Signed-off-by: Tony Thompson <Anthony.Thompson@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
  • Loading branch information
Tony Thompson authored and Catalin Marinas committed May 30, 2009
1 parent faa7bc5 commit ba3c026
Showing 1 changed file with 9 additions and 3 deletions.
12 changes: 9 additions & 3 deletions arch/arm/mm/proc-v7.S
Original file line number Diff line number Diff line change
Expand Up @@ -19,17 +19,23 @@

#include "proc-macros.S"

#define TTB_C (1 << 0)
#define TTB_S (1 << 1)
#define TTB_RGN_NC (0 << 3)
#define TTB_RGN_OC_WBWA (1 << 3)
#define TTB_RGN_OC_WT (2 << 3)
#define TTB_RGN_OC_WB (3 << 3)
#define TTB_NOS (1 << 5)
#define TTB_IRGN_NC ((0 << 0) | (0 << 6))
#define TTB_IRGN_WBWA ((0 << 0) | (1 << 6))
#define TTB_IRGN_WT ((1 << 0) | (0 << 6))
#define TTB_IRGN_WB ((1 << 0) | (1 << 6))

#ifndef CONFIG_SMP
#define TTB_FLAGS TTB_C|TTB_RGN_OC_WB @ mark PTWs cacheable, outer WB
/* PTWs cacheable, inner WB not shareable, outer WB not shareable */
#define TTB_FLAGS TTB_IRGN_WB|TTB_RGN_OC_WB
#else
#define TTB_FLAGS TTB_C|TTB_S|TTB_RGN_OC_WBWA @ mark PTWs cacheable and shared, outer WBWA
/* PTWs cacheable, inner WBWA shareable, outer WBWA not shareable */
#define TTB_FLAGS TTB_IRGN_WBWA|TTB_S|TTB_NOS|TTB_RGN_OC_WBWA
#endif

ENTRY(cpu_v7_proc_init)
Expand Down

0 comments on commit ba3c026

Please sign in to comment.