The patch set is tested on HiFive Unleashed A00 board and is based on mainline kernel v5.2-rc1. Its intended to add support for 32 MB spi-nor flash mounted on the board. Memory Device supports 4/32/ and 64 KB sectors size. The device id table is updated accordingly.
Flash parameter table for ISSI device is set to use macronix_quad_enable procedure to set the QE (quad-enable) bit of Status register. A unilaterlay block unlocking scheme is added in patch 2. These patches are based on original work done by Wesley Terpstra and/or Palmer Dabbelt: https://github.com/riscv/riscv-linux/commit/c94e267766d62bc9a669611c3d0c8ed5ea26569b Erase/Read/Write operations are verified on HiFive Unleashed board using mtd and flash utils (v1.5.2): 1. mtd_debug :Options available are : erase/read/write. 2. flashcp :Single utility that erases flash, writes a file to flash and verifies the data back. 3. flash_unlock: Unlock flash memory blocks.Arguments: are offset and number of blocks. 3. flash_lock: Lock flash memory blocks. Arguments: are offset and number of blocks. Unlock scheme clears the protection bits of all blocks in the Status register. Lock scheme: A basic implementation based on stm_lock scheme and is validated for different number of blocks passed to flash_lock. ISSI devices have top/bottom area selection in "function register" which is OTP memory. The changes along with other relevant patches are available under branch dev/sagark/spi-nor_v5.2-rc1 at: https://github.com/sagsifive/riscv-linux-hifive Revision history: V5<->V6: -Incorporated review comments from Vignesh. -Set addr width based on device size and if SPI_NOR_4B_OPCODES is set. -Added 4th block protect identifier (SPI_NOR_HAS_BP3) to flash_info structure -Changed flash_info: flag from u16 to u32 to accommodate SPI_NOR_HAS_BP3 -Prefix newly added function with spi_nor_xxx. -Dropped write_fr function, as updating OTP bit's present in function register doesn't seem to be a good idea. -Set lock/unlock schemes based on whether the ISSI device has locking support and BP3 bit present. V4<->V5: -Rebased to linux version v5.2-rc1. -Updated heading of this cover letter with sub-system, instead of just plain "add support for is25wp256..." V3<->V4: -Extracted comman code and renamed few stm functions so that it can be reused for issi lock implementation. -Added function's to read and write FR register, for selecting Top/Bottom area. V2<->V3: -Rebased patch to mainline v5.1 from earlier v5.1-rc5. -Updated commit messages, and cover letter with reference to git URL and author information. -Deferred flash_lock mechanism and can go as separate patch. V1<-> V2: -Incorporated changes suggested by reviewers regarding patch/cover letter versioning, references of patch. -Updated cover letter with description for flash operations verified with these changes. -Add support for unlocking is25xxxxxx device. -Add support for locking is25xxxxxx device. v1: -Add support for is25wp256 device. Sagar Shrikant Kadam (3): mtd: spi-nor: add support for is25wp256 mtd: spi-nor: add support to unlock flash device mtd: spi-nor: add locking support for is25xxxxx device drivers/mtd/spi-nor/spi-nor.c | 342 +++++++++++++++++++++++++++++++++++------- include/linux/mtd/spi-nor.h | 8 + 2 files changed, 294 insertions(+), 56 deletions(-) -- 1.9.1
