From: Arseniy Krasnov <avkrasnov@xxxxxxxxxxxxxx> [ 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> --- drivers/mtd/nand/raw/meson_nand.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/mtd/nand/raw/meson_nand.c b/drivers/mtd/nand/raw/meson_nand.c index b97adeee4cc14..4fd20e70aabd4 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); } -- 2.39.2