Unverified Commit 4b93f5fc authored by Alexander Usyskin's avatar Alexander Usyskin Committed by Rodrigo Vivi
Browse files

mtd: intel-dg: align 64bit read and write 



GSC NVM controller HW errors on quad access overlapping 1K border.
Align 64bit read and write to avoid readq/writeq over 1K border.

Reviewed-by: default avatarRaag Jadav <raag.jadav@intel.com>
Acked-by: default avatarMiquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: default avatarAlexander Usyskin <alexander.usyskin@intel.com>
Link: https://lore.kernel.org/r/20250617145159.3803852-6-alexander.usyskin@intel.com


Signed-off-by: default avatarRodrigo Vivi <rodrigo.vivi@intel.com>
parent 044c8be0

drivers/mtd/devices/mtd_intel_dg.c

+35 −0
Original line number Diff line number Diff line
@@ -246,6 +246,24 @@ static ssize_t idg_write(struct intel_dg_nvm *nvm, u8 region, 
		len_s -= to_shift;

	}



	if (!IS_ALIGNED(to, sizeof(u64)) &&

	    ((to ^ (to + len_s)) & GENMASK(31, 10))) {

		/*

		 * Workaround reads/writes across 1k-aligned addresses

		 * (start u32 before 1k, end u32 after)

		 * as this fails on hardware.

		 */

		u32 data;



		memcpy(&data, &buf[0], sizeof(u32));

		idg_nvm_write32(nvm, to, data);

		if (idg_nvm_error(nvm))

			return -EIO;

		buf += sizeof(u32);

		to += sizeof(u32);

		len_s -= sizeof(u32);

	}



	len8 = ALIGN_DOWN(len_s, sizeof(u64));

	for (i = 0; i < len8; i += sizeof(u64)) {

		u64 data;
@@ -303,6 +321,23 @@ static ssize_t idg_read(struct intel_dg_nvm *nvm, u8 region, 
		from += from_shift;

	}



	if (!IS_ALIGNED(from, sizeof(u64)) &&

	    ((from ^ (from + len_s)) & GENMASK(31, 10))) {

		/*

		 * Workaround reads/writes across 1k-aligned addresses

		 * (start u32 before 1k, end u32 after)

		 * as this fails on hardware.

		 */

		u32 data = idg_nvm_read32(nvm, from);



		if (idg_nvm_error(nvm))

			return -EIO;

		memcpy(&buf[0], &data, sizeof(data));

		len_s -= sizeof(u32);

		buf += sizeof(u32);

		from += sizeof(u32);

	}



	len8 = ALIGN_DOWN(len_s, sizeof(u64));

	for (i = 0; i < len8; i += sizeof(u64)) {

		u64 data = idg_nvm_read64(nvm, from + i);