From: Siarhei Siamashka Date: Wed, 24 Feb 2010 04:56:36 +0000 (-0500) Subject: OMAP3: workaround for ARM Cortex-A8 erratum 725233 X-Git-Url: http://git.denx.de/?p=u-boot%2Fu-boot-arm.git;a=commitdiff_plain;h=42d97d08838d4e010d80c92ad1300c426320dd18 OMAP3: workaround for ARM Cortex-A8 erratum 725233 725233: PLD instructions executed with PLD data forwarding enabled can result in a processor deadlock This deadlock can happen when NEON load instructions are used together with cache preload instructions (PLD). The problematic conditions can be triggered in-the-wild by NEON optimized functions from pixman library (http://cgit.freedesktop.org/pixman), which perform dynamic adjustment of prefetch distance. The workaround disables PLD data forwarding by setting PLD_FWD bit in L2 Cache Auxiliary Control Register as recommended in ARM Cortex-A8 errata list. The deadlock can only happen on r1pX revisions of Cortex-A8 (used in OMAP34xx/OMAP35xx). Performance impact of the workaround is practically non-existant. Signed-off-by: Siarhei Siamashka Signed-off-by: Sandeep Paulraj --- diff --git a/cpu/arm_cortexa8/omap3/board.c b/cpu/arm_cortexa8/omap3/board.c index 2aa69b3..7b78fa4 100644 --- a/cpu/arm_cortexa8/omap3/board.c +++ b/cpu/arm_cortexa8/omap3/board.c @@ -146,6 +146,12 @@ void setup_auxcr() __asm__ __volatile__("orr r0, r0, #1 << 5"); /* SMI instruction to call ROM Code API */ __asm__ __volatile__(".word 0xE1600070"); + /* Set PLD_FWD bit in L2AUXCR (Cortex-A8 erratum 725233 workaround) */ + __asm__ __volatile__("mov r12, #0x2"); + __asm__ __volatile__("mrc p15, 1, r0, c9, c0, 2"); + __asm__ __volatile__("orr r0, r0, #1 << 27"); + /* SMI instruction to call ROM Code API */ + __asm__ __volatile__(".word 0xE1600070"); __asm__ __volatile__("mov r0, %0":"=r"(i)); __asm__ __volatile__("mov r12, %0":"=r"(j)); }