From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marek Vasut Date: Wed, 5 Aug 2015 15:47:46 +0200 Subject: [U-Boot] [PATCH] sf: Make 4K sector support configurable In-Reply-To: References: <1438558136-5529-1-git-send-email-marex@denx.de> Message-ID: <201508051547.46417.marex@denx.de> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de On Wednesday, August 05, 2015 at 10:36:31 AM, Jagan Teki wrote: > On 5 August 2015 at 13:50, Jagan Teki wrote: > > On 3 August 2015 at 04:58, Marek Vasut wrote: > >> Make the support for 4K subpage I/O on a SPI NOR flash configurable. > >> A board which requires the SPI NOR to be accessed in larger 32KiB > >> or 64KiB pages can disable the 4K subpage support, but by default, > >> the support for 4K subpage I/O is enabled. The functionality of this > >> option is the same as CONFIG_MTD_SPI_NOR_USE_4K_SECTORS in Linux. > >> > >> This is extremely useful in case one uses UBI on a SPI NOR flash. > >> UBI needs at least 15k EBs and can not work on a flash which uses > >> 4k ones, so disabling the support for 4k subpages lets UBI work on > >> such flash. > >> > >> Signed-off-by: Marek Vasut > >> Cc: Jagan Teki > >> --- > >> > >> drivers/mtd/spi/Kconfig | 15 +++++++++++++++ > >> drivers/mtd/spi/sf_internal.h | 4 ++++ > >> 2 files changed, 19 insertions(+) > >> > >> diff --git a/drivers/mtd/spi/Kconfig b/drivers/mtd/spi/Kconfig > >> index 8b730ff..3f7433c 100644 > >> --- a/drivers/mtd/spi/Kconfig > >> +++ b/drivers/mtd/spi/Kconfig > >> @@ -86,6 +86,21 @@ config SPI_FLASH_WINBOND > >> > >> endif > >> > >> +config SPI_FLASH_USE_4K_SECTORS > >> + bool "Use small 4096 B erase sectors" > >> + depends on SPI_FLASH > >> + default y > >> + help > >> + Many flash memories support erasing small (4096 B) sectors. > >> Depending + on the usage this feature may provide performance > >> gain in comparison + to erasing whole blocks (32/64 KiB). > >> + Changing a small part of the flash's contents is usually > >> faster with + small sectors. On the other hand erasing should > >> be faster when using + 64 KiB block instead of 16 ? 4 KiB > >> sectors. > >> + > >> + Please note that some tools/drivers/filesystems may not work > >> with + 4096 B erase size (e.g. UBIFS requires 15 KiB as a > >> minimum). + > >> > >> config SPI_FLASH_DATAFLASH > >> > >> bool "AT45xxx DataFlash support" > >> depends on SPI_FLASH && DM_SPI_FLASH > >> > >> diff --git a/drivers/mtd/spi/sf_internal.h > >> b/drivers/mtd/spi/sf_internal.h index 9fb5557..9c95d56 100644 > >> --- a/drivers/mtd/spi/sf_internal.h > >> +++ b/drivers/mtd/spi/sf_internal.h > >> @@ -37,7 +37,11 @@ enum spi_read_cmds { > >> > >> /* sf param flags */ > >> enum { > >> > >> +#ifdef CONFIG_SPI_FLASH_USE_4K_SECTORS > >> > >> SECT_4K = 1 << 0, > >> > >> +#else > >> + SECT_4K = 0 << 0, > >> +#endif > >> > >> SECT_32K = 1 << 1, > >> E_FSR = 1 << 2, > >> SST_BP = 1 << 3, > >> > >> -- > >> 2.1.4 > > > > Reviewed-by: Jagan Teki > > Applied to u-boot-spi/master Excellent, thanks!