From 914a21ed9ceb403b178c30bedbc354e816b98e92 Mon Sep 17 00:00:00 2001 From: Daisuke Nojiri Date: Fri, 4 Sep 2015 14:32:49 -0700 Subject: vbnv: check alignment of nvram in advance Currently, erase operation only works if the region is sector-aligned. These asserts ensure we can erase the region when it's all used up. Erase operation can be updated to handle unaligned erases by read, update, write-back cycle. However, these asserts will still remain useful in case the adjacent region contains critical data and mis-updating it can cause a critical failure. Additionaly we should write a FAFT test but it's more reliable to catch it here since FAFT can fail in many ways. BUG=none BRANCH=master TEST=tested on samus using misaligned nvram region Change-Id: I3add4671ed354d9763e21bf96616c8aeca0cb777 Signed-off-by: Patrick Georgi Original-Commit-Id: fc001a4d3446cf96b76367dde492c3453aa948c6 Original-Change-Id: Ib4df8f620bf7531b345364fa4c3e274aba09f677 Original-Signed-off-by: Daisuke Nojiri Original-Reviewed-on: https://chromium-review.googlesource.com/297801 Reviewed-on: http://review.coreboot.org/11654 Tested-by: build bot (Jenkins) Reviewed-by: Patrick Georgi --- src/vendorcode/google/chromeos/vbnv_flash.c | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) diff --git a/src/vendorcode/google/chromeos/vbnv_flash.c b/src/vendorcode/google/chromeos/vbnv_flash.c index 656c3ea2a2..0ee9eaa943 100644 --- a/src/vendorcode/google/chromeos/vbnv_flash.c +++ b/src/vendorcode/google/chromeos/vbnv_flash.c @@ -19,6 +19,7 @@ * TODO: Make this CAR-friendly in case we use it on x86 some day. */ +#include #include #include #include @@ -111,6 +112,23 @@ static int init_vbnv(void) return 0; } +static void vbnv_is_erasable(void) +{ + /* + * We check whether the region is aligned or not in advance to ensure + * we can erase the region when it's all used up. + * + * The region offset & size are determined by fmap.dts yet the check can + * be confidently done only by the spi flash driver. We use the same + * check as the one used by spi_flash_cmd_erase, which happens to be + * common to all the spi flash parts we support. + * + * TODO: Check by calling can_erase implemented by each spi flash driver + */ + assert(!(region_device_offset(&nvram_region) % spi_flash->sector_size)); + assert(!(region_device_sz(&nvram_region) % spi_flash->sector_size)); +} + static int vbnv_flash_probe(void) { if (!spi_flash) { @@ -119,6 +137,11 @@ static int vbnv_flash_probe(void) printk(BIOS_ERR, "failed to probe spi flash\n"); return 1; } + /* + * Called here instead of init_vbnv to reduce impact on boot + * speed. + */ + vbnv_is_erasable(); } return 0; } -- cgit v1.2.3