diff options
Diffstat (limited to 'target/linux/ipq40xx/patches-4.14/050-0005-mtd-nand-force-drivers-to-explicitly-send-READ-PROG-.patch')
| -rw-r--r-- | target/linux/ipq40xx/patches-4.14/050-0005-mtd-nand-force-drivers-to-explicitly-send-READ-PROG-.patch | 94 |
1 files changed, 94 insertions, 0 deletions
diff --git a/target/linux/ipq40xx/patches-4.14/050-0005-mtd-nand-force-drivers-to-explicitly-send-READ-PROG-.patch b/target/linux/ipq40xx/patches-4.14/050-0005-mtd-nand-force-drivers-to-explicitly-send-READ-PROG-.patch new file mode 100644 index 0000000..e7e2e79 --- /dev/null +++ b/target/linux/ipq40xx/patches-4.14/050-0005-mtd-nand-force-drivers-to-explicitly-send-READ-PROG-.patch @@ -0,0 +1,94 @@ +From 25f815f66a141436df8a4c45e5d2765272aea2ac Mon Sep 17 00:00:00 2001 +From: Boris Brezillon <boris.brezillon@free-electrons.com> +Date: Thu, 30 Nov 2017 18:01:30 +0100 +Subject: [PATCH 5/7] mtd: nand: force drivers to explicitly send READ/PROG + commands + +The core currently send the READ0 and SEQIN+PAGEPROG commands in +nand_do_read/write_ops(). This is inconsistent with +->read/write_oob[_raw]() hooks behavior which are expected to send +these commands. + +There's already a flag (NAND_ECC_CUSTOM_PAGE_ACCESS) to inform the core +that a specific controller wants to send the READ/SEQIN+PAGEPROG +commands on its own, but it's an opt-in flag, and existing drivers are +unlikely to be updated to pass it. + +Moreover, some controllers cannot dissociate the READ/PAGEPROG commands +from the associated data transfer and ECC engine activation, and +developers have to hack things in their ->cmdfunc() implementation to +handle such complex cases, or have to accept the perf penalty of sending +twice the same command. +To address this problem we are planning on adding a new interface which +is passed all information about a NAND operation (including the amount +of data to transfer) and replacing all calls to ->cmdfunc() to calls to +this new ->exec_op() hook. But, in order to do that, we need to have all +->cmdfunc() calls placed near their associated ->read/write_buf/byte() +calls. + +Modify the core and relevant drivers to make NAND_ECC_CUSTOM_PAGE_ACCESS +the default case, and remove this flag. + +Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> +[miquel.raynal@free-electrons.com: tested, fixed and rebased on nand/next] +Signed-off-by: Miquel Raynal <miquel.raynal@free-electrons.com> +Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com> +--- + drivers/mtd/nand/qcom_nandc.c | 11 +++++++++++ + 1 file changed, 11 insertions(+) + +--- a/drivers/mtd/nand/qcom_nandc.c ++++ b/drivers/mtd/nand/qcom_nandc.c +@@ -1725,6 +1725,7 @@ static int qcom_nandc_read_page(struct m + u8 *data_buf, *oob_buf = NULL; + int ret; + ++ nand_read_page_op(chip, page, 0, NULL, 0); + data_buf = buf; + oob_buf = oob_required ? chip->oob_poi : NULL; + +@@ -1750,6 +1751,7 @@ static int qcom_nandc_read_page_raw(stru + int i, ret; + int read_loc; + ++ nand_read_page_op(chip, page, 0, NULL, 0); + data_buf = buf; + oob_buf = chip->oob_poi; + +@@ -1850,6 +1852,8 @@ static int qcom_nandc_write_page(struct + u8 *data_buf, *oob_buf; + int i, ret; + ++ nand_prog_page_begin_op(chip, page, 0, NULL, 0); ++ + clear_read_regs(nandc); + clear_bam_transaction(nandc); + +@@ -1902,6 +1906,9 @@ static int qcom_nandc_write_page(struct + + free_descs(nandc); + ++ if (!ret) ++ ret = nand_prog_page_end_op(chip); ++ + return ret; + } + +@@ -1916,6 +1923,7 @@ static int qcom_nandc_write_page_raw(str + u8 *data_buf, *oob_buf; + int i, ret; + ++ nand_prog_page_begin_op(chip, page, 0, NULL, 0); + clear_read_regs(nandc); + clear_bam_transaction(nandc); + +@@ -1970,6 +1978,9 @@ static int qcom_nandc_write_page_raw(str + + free_descs(nandc); + ++ if (!ret) ++ ret = nand_prog_page_end_op(chip); ++ + return ret; + } + |