Patch "mtd: rawnand: meson: invalidate cache on polling ECC bit" has been added to the 5.4-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    mtd: rawnand: meson: invalidate cache on polling ECC bit

to the 5.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     mtd-rawnand-meson-invalidate-cache-on-polling-ecc-bi.patch
and it can be found in the queue-5.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 255b7920d4c826c6b33be0397fd97d0ddb8a1d45
Author: Arseniy Krasnov <avkrasnov@xxxxxxxxxxxxxx>
Date:   Mon Mar 13 10:32:44 2023 +0300

    mtd: rawnand: meson: invalidate cache on polling ECC bit
    
    [ Upstream commit e732e39ed9929c05fd219035bc9653ba4100d4fa ]
    
    'info_buf' memory is cached and driver polls ECC bit in it. This bit
    is set by the NAND controller. If 'usleep_range()' returns before device
    sets this bit, 'info_buf' will be cached and driver won't see update of
    this bit and will loop forever.
    
    Fixes: 8fae856c5350 ("mtd: rawnand: meson: add support for Amlogic NAND flash controller")
    Signed-off-by: Arseniy Krasnov <AVKrasnov@xxxxxxxxxxxxxx>
    Reviewed-by: Neil Armstrong <neil.armstrong@xxxxxxxxxx>
    Signed-off-by: Miquel Raynal <miquel.raynal@xxxxxxxxxxx>
    Link: https://lore.kernel.org/linux-mtd/d4ef0bd6-816e-f6fa-9385-f05f775f0ae2@xxxxxxxxxxxxxx
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/mtd/nand/raw/meson_nand.c b/drivers/mtd/nand/raw/meson_nand.c
index a65aadb54af68..240b493abb86f 100644
--- a/drivers/mtd/nand/raw/meson_nand.c
+++ b/drivers/mtd/nand/raw/meson_nand.c
@@ -172,6 +172,7 @@ struct meson_nfc {
 
 	dma_addr_t daddr;
 	dma_addr_t iaddr;
+	u32 info_bytes;
 
 	unsigned long assigned_cs;
 };
@@ -499,6 +500,7 @@ static int meson_nfc_dma_buffer_setup(struct nand_chip *nand, void *databuf,
 					 nfc->daddr, datalen, dir);
 			return ret;
 		}
+		nfc->info_bytes = infolen;
 		cmd = GENCMDIADDRL(NFC_CMD_AIL, nfc->iaddr);
 		writel(cmd, nfc->reg_base + NFC_REG_CMD);
 
@@ -516,8 +518,10 @@ static void meson_nfc_dma_buffer_release(struct nand_chip *nand,
 	struct meson_nfc *nfc = nand_get_controller_data(nand);
 
 	dma_unmap_single(nfc->dev, nfc->daddr, datalen, dir);
-	if (infolen)
+	if (infolen) {
 		dma_unmap_single(nfc->dev, nfc->iaddr, infolen, dir);
+		nfc->info_bytes = 0;
+	}
 }
 
 static int meson_nfc_read_buf(struct nand_chip *nand, u8 *buf, int len)
@@ -706,6 +710,8 @@ static void meson_nfc_check_ecc_pages_valid(struct meson_nfc *nfc,
 		usleep_range(10, 15);
 		/* info is updated by nfc dma engine*/
 		smp_rmb();
+		dma_sync_single_for_cpu(nfc->dev, nfc->iaddr, nfc->info_bytes,
+					DMA_FROM_DEVICE);
 		ret = *info & ECC_COMPLETE;
 	} while (!ret);
 }