From 21a268069203cc72d1b2990bc68386516fabc274 Mon Sep 17 00:00:00 2001 From: Miquel Raynal Date: Fri, 7 Sep 2018 16:29:54 +0200 Subject: [PATCH 1/4] mtd: rawnand: marvell: prevent harmless warnings Since the addition of WARN_ON() in nand_subop_get_data/addr_len() helpers, this driver will produce harmless warnings (mostly at probe) just because it always calls the nand_subop_get_data_len() helper in the parsing function (even on non-data instructions, where this value is meaningless and unneeded). Fix these warnings by deriving the length only when it is relevant. Fixes: 760c435e0f85 ("mtd: rawnand: make subop helpers return unsigned values") Signed-off-by: Miquel Raynal Signed-off-by: Boris Brezillon --- drivers/mtd/nand/raw/marvell_nand.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/mtd/nand/raw/marvell_nand.c b/drivers/mtd/nand/raw/marvell_nand.c index 7af4d6213ee5..bc2ef5209783 100644 --- a/drivers/mtd/nand/raw/marvell_nand.c +++ b/drivers/mtd/nand/raw/marvell_nand.c @@ -1547,7 +1547,7 @@ static void marvell_nfc_parse_instructions(struct nand_chip *chip, for (op_id = 0; op_id < subop->ninstrs; op_id++) { unsigned int offset, naddrs; const u8 *addrs; - int len = nand_subop_get_data_len(subop, op_id); + int len; instr = &subop->instrs[op_id]; @@ -1593,6 +1593,7 @@ static void marvell_nfc_parse_instructions(struct nand_chip *chip, nfc_op->ndcb[0] |= NDCB0_CMD_XTYPE(XTYPE_MONOLITHIC_RW) | NDCB0_LEN_OVRD; + len = nand_subop_get_data_len(subop, op_id); nfc_op->ndcb[3] |= round_up(len, FIFO_DEPTH); } nfc_op->data_delay_ns = instr->delay_ns; @@ -1606,6 +1607,7 @@ static void marvell_nfc_parse_instructions(struct nand_chip *chip, nfc_op->ndcb[0] |= NDCB0_CMD_XTYPE(XTYPE_MONOLITHIC_RW) | NDCB0_LEN_OVRD; + len = nand_subop_get_data_len(subop, op_id); nfc_op->ndcb[3] |= round_up(len, FIFO_DEPTH); } nfc_op->data_delay_ns = instr->delay_ns; From cf51e4b9c34407bf0c3d9b582b7837e047e1df47 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Thu, 13 Sep 2018 14:58:49 +0900 Subject: [PATCH 2/4] mtd: rawnand: denali: fix a race condition when DMA is kicked I thought the read-back of the DMA_ENABLE register was unnecessary (at least it is working on my boards), then deleted it in commit 586a2c52909d ("mtd: nand: denali: squash denali_enable_dma() helper into caller"). Sorry, I was wrong - it caused a timing issue on Cyclone5 SoCFPGAs. Revive the register read-back, commenting why this is necessary. Fixes: 586a2c52909d ("mtd: nand: denali: squash denali_enable_dma() helper into caller") Cc: Reported-by: Steffen Trumtrar Signed-off-by: Masahiro Yamada Reviewed-by: Miquel Raynal Signed-off-by: Boris Brezillon --- drivers/mtd/nand/raw/denali.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/mtd/nand/raw/denali.c b/drivers/mtd/nand/raw/denali.c index 67b2065e7a19..b864b93dd289 100644 --- a/drivers/mtd/nand/raw/denali.c +++ b/drivers/mtd/nand/raw/denali.c @@ -596,6 +596,12 @@ static int denali_dma_xfer(struct denali_nand_info *denali, void *buf, } iowrite32(DMA_ENABLE__FLAG, denali->reg + DMA_ENABLE); + /* + * The ->setup_dma() hook kicks DMA by using the data/command + * interface, which belongs to a different AXI port from the + * register interface. Read back the register to avoid a race. + */ + ioread32(denali->reg + DMA_ENABLE); denali_reset_irq(denali); denali->setup_dma(denali, dma_addr, page, write); From 85516a9881a31e2c7a8d10f4697f3adcccc7cef1 Mon Sep 17 00:00:00 2001 From: Miquel Raynal Date: Fri, 7 Sep 2018 16:35:54 +0200 Subject: [PATCH 3/4] mtd: partitions: fix unbalanced of_node_get/put() While at first mtd_part_of_parse() would just call of_get_chil_by_name(), it has been patched to deal with sub-partitions and will now directly manipulate the node returned by mtd_get_of_node() if the MTD device is a partition. A of_node_put() was a bit below in the code, to balance the of_get_child_by_name(). However, despite its name, mtd_get_of_node() does not take a reference on the OF node. It is a simple helper hiding some pointer logic to retrieve the OF node related to an MTD device. The direct effect of such unbalanced reference counting is visible by rmmod'ing any module that would have added MTD partitions: OF: ERROR: Bad of_node_put() on As it seems normal to get a reference on the OF node during the of_property_for_each_string() that follows, add a call to of_node_get() when relevant. Fixes: 76a832254ab0 ("mtd: partitions: use DT info for parsing partitions with "compatible" prop") Cc: stable@vger.kernel.org Signed-off-by: Miquel Raynal Signed-off-by: Boris Brezillon --- drivers/mtd/mtdpart.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/mtd/mtdpart.c b/drivers/mtd/mtdpart.c index 52e2cb35fc79..99c460facd5e 100644 --- a/drivers/mtd/mtdpart.c +++ b/drivers/mtd/mtdpart.c @@ -873,8 +873,11 @@ static int mtd_part_of_parse(struct mtd_info *master, int ret, err = 0; np = mtd_get_of_node(master); - if (!mtd_is_partition(master)) + if (mtd_is_partition(master)) + of_node_get(np); + else np = of_get_child_by_name(np, "partitions"); + of_property_for_each_string(np, "compatible", prop, compat) { parser = mtd_part_get_compatible_parser(compat); if (!parser) From 4a3e85f2674cbfb81052059107d0165269778e2f Mon Sep 17 00:00:00 2001 From: Boris Brezillon Date: Mon, 17 Sep 2018 16:31:30 +0200 Subject: [PATCH 4/4] mtd: devices: m25p80: Make sure the buffer passed in op is DMA-able As documented in spi-mem.h, spi_mem_op->data.buf.{in,out} must be DMA-able, and commit 4120f8d158ef ("mtd: spi-nor: Use the spi_mem_xx() API") failed to follow this rule as buffers passed to ->{read,write}_reg() are usually placed on the stack. Fix that by allocating a scratch buffer and copying the data around. Fixes: 4120f8d158ef ("mtd: spi-nor: Use the spi_mem_xx() API") Reported-by: Jarkko Nikula Cc: Signed-off-by: Boris Brezillon Tested-by: Jarkko Nikula Reviewed-by: Jarkko Nikula --- drivers/mtd/devices/m25p80.c | 26 +++++++++++++++++++++++--- 1 file changed, 23 insertions(+), 3 deletions(-) diff --git a/drivers/mtd/devices/m25p80.c b/drivers/mtd/devices/m25p80.c index cbfafc453274..270d3c9580c5 100644 --- a/drivers/mtd/devices/m25p80.c +++ b/drivers/mtd/devices/m25p80.c @@ -39,13 +39,23 @@ static int m25p80_read_reg(struct spi_nor *nor, u8 code, u8 *val, int len) struct spi_mem_op op = SPI_MEM_OP(SPI_MEM_OP_CMD(code, 1), SPI_MEM_OP_NO_ADDR, SPI_MEM_OP_NO_DUMMY, - SPI_MEM_OP_DATA_IN(len, val, 1)); + SPI_MEM_OP_DATA_IN(len, NULL, 1)); + void *scratchbuf; int ret; + scratchbuf = kmalloc(len, GFP_KERNEL); + if (!scratchbuf) + return -ENOMEM; + + op.data.buf.in = scratchbuf; ret = spi_mem_exec_op(flash->spimem, &op); if (ret < 0) dev_err(&flash->spimem->spi->dev, "error %d reading %x\n", ret, code); + else + memcpy(val, scratchbuf, len); + + kfree(scratchbuf); return ret; } @@ -56,9 +66,19 @@ static int m25p80_write_reg(struct spi_nor *nor, u8 opcode, u8 *buf, int len) struct spi_mem_op op = SPI_MEM_OP(SPI_MEM_OP_CMD(opcode, 1), SPI_MEM_OP_NO_ADDR, SPI_MEM_OP_NO_DUMMY, - SPI_MEM_OP_DATA_OUT(len, buf, 1)); + SPI_MEM_OP_DATA_OUT(len, NULL, 1)); + void *scratchbuf; + int ret; - return spi_mem_exec_op(flash->spimem, &op); + scratchbuf = kmemdup(buf, len, GFP_KERNEL); + if (!scratchbuf) + return -ENOMEM; + + op.data.buf.out = scratchbuf; + ret = spi_mem_exec_op(flash->spimem, &op); + kfree(scratchbuf); + + return ret; } static ssize_t m25p80_write(struct spi_nor *nor, loff_t to, size_t len,