From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from smtp-4h.backboneservers.com ([66.6.63.245]) by bombadil.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1SlkLa-0007kY-Gd for barebox@lists.infradead.org; Mon, 02 Jul 2012 17:23:39 +0000 Received: from Debian-exim by smtp-4h.backboneservers.com with spam-scanned (Exim 4.72) (envelope-from ) id 1SlkLM-0002AI-EM for barebox@lists.infradead.org; Mon, 02 Jul 2012 17:23:30 +0000 From: steve@scheftech.com Date: Mon, 2 Jul 2012 13:22:33 -0400 Message-Id: <1341249753-5480-1-git-send-email-steve@scheftech.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: barebox-bounces@lists.infradead.org Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: [PATCH] Avoid SDRAM access crash To: barebox@lists.infradead.org Cc: Steve Schefter From: Steve Schefter When remapping the SDRAM with the MMU enabled, we need to ensure that the translation tables are not still in cache before invalidating the TLB. Failure to do so will result in the following crash approximately 50% of the time: booting kernel from /dev/nand0.kernel.bb Image Name: Linux-3.3.0PD12.0.0 OS: Linux Architecture: ARM Type: Kernel Image Compression: uncompressed Data Size: 3384824 Bytes = 3.2 MB Load Address: 80008000 Entry Point: 80008000 unable to handle paging request at address 0x80028000 pc : [<8f01f280>] lr : [<8f005330>] sp : 8cfff9b0 ip : 0000003f fp : 00000000 r10: 00001000 r9 : 00000000 r8 : 8d2a8f70 r7 : 8f043818 r6 : 0033a5f8 r5 : 8f04381c r4 : 00001000 r3 : 80028000 r2 : 00000fff r1 : 8d2a8f71 r0 : 80028000 Flags: nzCv IRQs off FIQs off Mode SVC_32 [<8f01f280>] (memcpy+0x18/0x20) from [<8f005330>] (uimage_sdram_flush+0x90/0xb8) [<8f005330>] (uimage_sdram_flush+0x90/0xb8) from [<8f0053a4>] (uncompress_copy+0x4c/0x74) Signed-off-by: Steve Schefter --- arch/arm/cpu/mmu.c | 6 ++++++ 1 files changed, 6 insertions(+), 0 deletions(-) diff --git a/arch/arm/cpu/mmu.c b/arch/arm/cpu/mmu.c index c19f931..4ff0430 100644 --- a/arch/arm/cpu/mmu.c +++ b/arch/arm/cpu/mmu.c @@ -165,6 +165,12 @@ static int arm_mmu_remap_sdram(struct memory_bank *bank) pte += 256; } + asm volatile ( + "bl __mmu_cache_flush;" + : + : + : "r0", "r1", "r2", "r3", "r6", "r10", "r12", "lr", "cc", "memory" + ); tlb_invalidate(); return 0; -- 1.7.4.1 _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox