* [PATCH v2 0/2] fix some gpmi nand driver bugs @ 2020-12-09 3:51 Han Xu 2020-12-09 3:51 ` [PATCH v2 1/2] mtd: rawnand: gpmi: Fix the driver only sense CS0 R/B issue Han Xu 2020-12-09 3:51 ` [PATCH v2 2/2] mtd: rawnand: gpmi: Fix the random DMA timeout issue Han Xu 0 siblings, 2 replies; 7+ messages in thread From: Han Xu @ 2020-12-09 3:51 UTC (permalink / raw) To: miquel.raynal, s.hauer; +Cc: han.xu, linux-mtd fix gpmi nand driver cannot sense multi-cs chip issue and the random DMA timeout bug. changes from v1: * fixed the typo * removed the fixes tag * added Sascha's review tag Han Xu (2): mtd: rawnand: gpmi: Fix the driver only sense CS0 R/B issue mtd: rawnand: gpmi: Fix the random DMA timeout issue drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c | 36 +++++++++++++++------- drivers/mtd/nand/raw/gpmi-nand/gpmi-regs.h | 1 + 2 files changed, 26 insertions(+), 11 deletions(-) -- 2.17.1 ______________________________________________________ Linux MTD discussion mailing list http://lists.infradead.org/mailman/listinfo/linux-mtd/ ^ permalink raw reply [flat|nested] 7+ messages in thread
* [PATCH v2 1/2] mtd: rawnand: gpmi: Fix the driver only sense CS0 R/B issue 2020-12-09 3:51 [PATCH v2 0/2] fix some gpmi nand driver bugs Han Xu @ 2020-12-09 3:51 ` Han Xu 2020-12-10 9:45 ` Sascha Hauer ` (2 more replies) 2020-12-09 3:51 ` [PATCH v2 2/2] mtd: rawnand: gpmi: Fix the random DMA timeout issue Han Xu 1 sibling, 3 replies; 7+ messages in thread From: Han Xu @ 2020-12-09 3:51 UTC (permalink / raw) To: miquel.raynal, s.hauer; +Cc: han.xu, linux-mtd set the GPMI CTRL1 GANGED_RDYBUSY bit so dirver can sense the R/B signal from all CS. For the NAND chip MT29F64G08AFAAAWP, only the first chip detected without the patch. [ 3.764118] nand: device found, Manufacturer ID: 0x2c, Chip ID: 0x68 [ 3.770613] nand: Micron MT29F64G08AFAAAWP [ 3.774752] nand: 4096 MiB, SLC, erase size: 1024 KiB, page size: 8192, OOB size: 448 [ 3.786421] Bad block table found at page 524160, version 0x01 [ 3.792730] Bad block table found at page 524032, version 0x01 After applying the patch [ 3.764445] nand: device found, Manufacturer ID: 0x2c, Chip ID: 0x68 [ 3.770941] nand: Micron MT29F64G08AFAAAWP [ 3.775080] nand: 4096 MiB, SLC, erase size: 1024 KiB, page size: 8192, OOB size: 448 [ 3.784390] nand: 2 chips detected [ 3.790900] Bad block table found at page 524160, version 0x01 [ 3.796776] Bad block table found at page 1048448, version 0x01 Signed-off-by: Han Xu <han.xu@nxp.com> --- drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c | 6 ++++-- drivers/mtd/nand/raw/gpmi-nand/gpmi-regs.h | 1 + 2 files changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c b/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c index 0d30f3fbb045..b06e202cdd0d 100644 --- a/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c +++ b/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c @@ -181,9 +181,11 @@ static int gpmi_init(struct gpmi_nand_data *this) /* * Decouple the chip select from dma channel. We use dma0 for all - * the chips. + * the chips, force all NAND RDY_BUSY inputs to be sourced from + * RDY_BUSY0. */ - writel(BM_GPMI_CTRL1_DECOUPLE_CS, r->gpmi_regs + HW_GPMI_CTRL1_SET); + writel(BM_GPMI_CTRL1_DECOUPLE_CS | BM_GPMI_CTRL1_GANGED_RDYBUSY, + r->gpmi_regs + HW_GPMI_CTRL1_SET); err_out: pm_runtime_mark_last_busy(this->dev); diff --git a/drivers/mtd/nand/raw/gpmi-nand/gpmi-regs.h b/drivers/mtd/nand/raw/gpmi-nand/gpmi-regs.h index f5e4f26c34da..fc31fd084dcf 100644 --- a/drivers/mtd/nand/raw/gpmi-nand/gpmi-regs.h +++ b/drivers/mtd/nand/raw/gpmi-nand/gpmi-regs.h @@ -107,6 +107,7 @@ #define BV_GPMI_CTRL1_WRN_DLY_SEL_7_TO_12NS 0x2 #define BV_GPMI_CTRL1_WRN_DLY_SEL_NO_DELAY 0x3 +#define BM_GPMI_CTRL1_GANGED_RDYBUSY (1 << 19) #define BM_GPMI_CTRL1_BCH_MODE (1 << 18) #define BP_GPMI_CTRL1_DLL_ENABLE 17 -- 2.17.1 ______________________________________________________ Linux MTD discussion mailing list http://lists.infradead.org/mailman/listinfo/linux-mtd/ ^ permalink raw reply related [flat|nested] 7+ messages in thread
* Re: [PATCH v2 1/2] mtd: rawnand: gpmi: Fix the driver only sense CS0 R/B issue 2020-12-09 3:51 ` [PATCH v2 1/2] mtd: rawnand: gpmi: Fix the driver only sense CS0 R/B issue Han Xu @ 2020-12-10 9:45 ` Sascha Hauer 2020-12-10 9:54 ` Fabio Estevam 2020-12-10 21:39 ` Miquel Raynal 2 siblings, 0 replies; 7+ messages in thread From: Sascha Hauer @ 2020-12-10 9:45 UTC (permalink / raw) To: Han Xu; +Cc: linux-mtd, miquel.raynal On Tue, Dec 08, 2020 at 09:51:03PM -0600, Han Xu wrote: > set the GPMI CTRL1 GANGED_RDYBUSY bit so dirver can sense the R/B signal > from all CS. > > For the NAND chip MT29F64G08AFAAAWP, only the first chip detected > without the patch. > > [ 3.764118] nand: device found, Manufacturer ID: 0x2c, Chip ID: 0x68 > [ 3.770613] nand: Micron MT29F64G08AFAAAWP > [ 3.774752] nand: 4096 MiB, SLC, erase size: 1024 KiB, page size: 8192, OOB size: 448 > [ 3.786421] Bad block table found at page 524160, version 0x01 > [ 3.792730] Bad block table found at page 524032, version 0x01 > > After applying the patch > > [ 3.764445] nand: device found, Manufacturer ID: 0x2c, Chip ID: 0x68 > [ 3.770941] nand: Micron MT29F64G08AFAAAWP > [ 3.775080] nand: 4096 MiB, SLC, erase size: 1024 KiB, page size: 8192, OOB size: 448 > [ 3.784390] nand: 2 chips detected > [ 3.790900] Bad block table found at page 524160, version 0x01 > [ 3.796776] Bad block table found at page 1048448, version 0x01 > > Signed-off-by: Han Xu <han.xu@nxp.com> Acked-by: Sascha Hauer <s.hauer@pengutronix.de> Sascha > --- > drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c | 6 ++++-- > drivers/mtd/nand/raw/gpmi-nand/gpmi-regs.h | 1 + > 2 files changed, 5 insertions(+), 2 deletions(-) > > diff --git a/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c b/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c > index 0d30f3fbb045..b06e202cdd0d 100644 > --- a/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c > +++ b/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c > @@ -181,9 +181,11 @@ static int gpmi_init(struct gpmi_nand_data *this) > > /* > * Decouple the chip select from dma channel. We use dma0 for all > - * the chips. > + * the chips, force all NAND RDY_BUSY inputs to be sourced from > + * RDY_BUSY0. > */ > - writel(BM_GPMI_CTRL1_DECOUPLE_CS, r->gpmi_regs + HW_GPMI_CTRL1_SET); > + writel(BM_GPMI_CTRL1_DECOUPLE_CS | BM_GPMI_CTRL1_GANGED_RDYBUSY, > + r->gpmi_regs + HW_GPMI_CTRL1_SET); > > err_out: > pm_runtime_mark_last_busy(this->dev); > diff --git a/drivers/mtd/nand/raw/gpmi-nand/gpmi-regs.h b/drivers/mtd/nand/raw/gpmi-nand/gpmi-regs.h > index f5e4f26c34da..fc31fd084dcf 100644 > --- a/drivers/mtd/nand/raw/gpmi-nand/gpmi-regs.h > +++ b/drivers/mtd/nand/raw/gpmi-nand/gpmi-regs.h > @@ -107,6 +107,7 @@ > #define BV_GPMI_CTRL1_WRN_DLY_SEL_7_TO_12NS 0x2 > #define BV_GPMI_CTRL1_WRN_DLY_SEL_NO_DELAY 0x3 > > +#define BM_GPMI_CTRL1_GANGED_RDYBUSY (1 << 19) > #define BM_GPMI_CTRL1_BCH_MODE (1 << 18) > > #define BP_GPMI_CTRL1_DLL_ENABLE 17 > -- > 2.17.1 > > -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | ______________________________________________________ Linux MTD discussion mailing list http://lists.infradead.org/mailman/listinfo/linux-mtd/ ^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH v2 1/2] mtd: rawnand: gpmi: Fix the driver only sense CS0 R/B issue 2020-12-09 3:51 ` [PATCH v2 1/2] mtd: rawnand: gpmi: Fix the driver only sense CS0 R/B issue Han Xu 2020-12-10 9:45 ` Sascha Hauer @ 2020-12-10 9:54 ` Fabio Estevam 2020-12-10 21:39 ` Miquel Raynal 2 siblings, 0 replies; 7+ messages in thread From: Fabio Estevam @ 2020-12-10 9:54 UTC (permalink / raw) To: Han Xu; +Cc: Sascha Hauer, linux-mtd, Miquel Raynal On Wed, Dec 9, 2020 at 12:52 AM Han Xu <han.xu@nxp.com> wrote: > > set the GPMI CTRL1 GANGED_RDYBUSY bit so dirver can sense the R/B signal > from all CS. s/dirver/driver. Reviewed-by: Fabio Estevam <festevam@gmail.com> ______________________________________________________ Linux MTD discussion mailing list http://lists.infradead.org/mailman/listinfo/linux-mtd/ ^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH v2 1/2] mtd: rawnand: gpmi: Fix the driver only sense CS0 R/B issue 2020-12-09 3:51 ` [PATCH v2 1/2] mtd: rawnand: gpmi: Fix the driver only sense CS0 R/B issue Han Xu 2020-12-10 9:45 ` Sascha Hauer 2020-12-10 9:54 ` Fabio Estevam @ 2020-12-10 21:39 ` Miquel Raynal 2 siblings, 0 replies; 7+ messages in thread From: Miquel Raynal @ 2020-12-10 21:39 UTC (permalink / raw) To: Han Xu, miquel.raynal, s.hauer; +Cc: linux-mtd On Wed, 2020-12-09 at 03:51:03 UTC, Han Xu wrote: > set the GPMI CTRL1 GANGED_RDYBUSY bit so dirver can sense the R/B signal > from all CS. > > For the NAND chip MT29F64G08AFAAAWP, only the first chip detected > without the patch. > > [ 3.764118] nand: device found, Manufacturer ID: 0x2c, Chip ID: 0x68 > [ 3.770613] nand: Micron MT29F64G08AFAAAWP > [ 3.774752] nand: 4096 MiB, SLC, erase size: 1024 KiB, page size: 8192, OOB size: 448 > [ 3.786421] Bad block table found at page 524160, version 0x01 > [ 3.792730] Bad block table found at page 524032, version 0x01 > > After applying the patch > > [ 3.764445] nand: device found, Manufacturer ID: 0x2c, Chip ID: 0x68 > [ 3.770941] nand: Micron MT29F64G08AFAAAWP > [ 3.775080] nand: 4096 MiB, SLC, erase size: 1024 KiB, page size: 8192, OOB size: 448 > [ 3.784390] nand: 2 chips detected > [ 3.790900] Bad block table found at page 524160, version 0x01 > [ 3.796776] Bad block table found at page 1048448, version 0x01 > > Signed-off-by: Han Xu <han.xu@nxp.com> > Acked-by: Sascha Hauer <s.hauer@pengutronix.de> > Reviewed-by: Fabio Estevam <festevam@gmail.com> Applied to https://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux.git nand/next, thanks. Miquel ______________________________________________________ Linux MTD discussion mailing list http://lists.infradead.org/mailman/listinfo/linux-mtd/ ^ permalink raw reply [flat|nested] 7+ messages in thread
* [PATCH v2 2/2] mtd: rawnand: gpmi: Fix the random DMA timeout issue 2020-12-09 3:51 [PATCH v2 0/2] fix some gpmi nand driver bugs Han Xu 2020-12-09 3:51 ` [PATCH v2 1/2] mtd: rawnand: gpmi: Fix the driver only sense CS0 R/B issue Han Xu @ 2020-12-09 3:51 ` Han Xu 2020-12-10 21:39 ` Miquel Raynal 1 sibling, 1 reply; 7+ messages in thread From: Han Xu @ 2020-12-09 3:51 UTC (permalink / raw) To: miquel.raynal, s.hauer; +Cc: han.xu, linux-mtd To get better performance, current gpmi driver collected and chained all small DMA transfers in gpmi_nfc_exec_op, the whole chain triggered and wait for complete at the end. But some random DMA timeout found in this new driver, with the help of ftrace, we found the root cause is as follows: Take gpmi_ecc_read_page() as an example, gpmi_nfc_exec_op collected 6 DMA transfers and the DMA chain triggered at the end. It waits for bch completion and check jiffies if it's timeout. The typical function graph shown below, 63.216351 | 1) | gpmi_ecc_read_page() { 63.216352 | 1) 0.750 us | gpmi_bch_layout_std(); 63.216354 | 1) | gpmi_nfc_exec_op() { 63.216355 | 1) | gpmi_chain_command() { 63.216356 | 1) | mxs_dma_prep_slave_sg() { 63.216357 | 1) | /* mxs chan ccw idx: 0 */ 63.216358 | 1) 1.750 us | } 63.216359 | 1) | mxs_dma_prep_slave_sg() { 63.216360 | 1) | /* mxs chan ccw idx: 1 */ 63.216361 | 1) 2.000 us | } 63.216361 | 1) 6.500 us | } 63.216362 | 1) | gpmi_chain_command() { 63.216363 | 1) | mxs_dma_prep_slave_sg() { 63.216364 | 1) | /* mxs chan ccw idx: 2 */ 63.216365 | 1) 1.750 us | } 63.216366 | 1) | mxs_dma_prep_slave_sg() { 63.216367 | 1) | /* mxs chan ccw idx: 3 */ 63.216367 | 1) 1.750 us | } 63.216368 | 1) 5.875 us | } 63.216369 | 1) | /* gpmi_chain_wait_ready */ 63.216370 | 1) | mxs_dma_prep_slave_sg() { 63.216372 | 1) | /* mxs chan ccw idx: 4 */ 63.216373 | 1) 3.000 us | } 63.216374 | 1) | /* gpmi_chain_data_read */ 63.216376 | 1) | mxs_dma_prep_slave_sg() { 63.216377 | 1) | /* mxs chan ccw idx: 5 */ 63.216378 | 1) 2.000 us | } 63.216379 | 1) 1.125 us | mxs_dma_tx_submit(); 63.216381 | 1) 1.000 us | mxs_dma_enable_chan(); 63.216712 | 0) 2.625 us | mxs_dma_int_handler(); 63.216717 | 0) 4.250 us | bch_irq(); 63.216723 | 0) 1.250 us | mxs_dma_tasklet(); 63.216723 | 1) | /* jiffies left 250 */ 63.216725 | 1) ! 372.000 us | } 63.216726 | 1) 2.625 us | gpmi_count_bitflips(); 63.216730 | 1) ! 379.125 us | } but it's not gurantee that bch irq handled always after dma irq handled, sometimes bch_irq comes first and gpmi_nfc_exec_op won't wait anymore, another gpmi_nfc_exec_op may get invoked before last DMA chain IRQ handled, this messed up the next DMA chain and causes DMA timeout. Check the trace log when issue happened. 63.218923 | 1) | gpmi_ecc_read_page() { 63.218924 | 1) 0.625 us | gpmi_bch_layout_std(); 63.218926 | 1) | gpmi_nfc_exec_op() { 63.218927 | 1) | gpmi_chain_command() { 63.218928 | 1) | mxs_dma_prep_slave_sg() { 63.218929 | 1) | /* mxs chan ccw idx: 0 */ 63.218929 | 1) 1.625 us | } 63.218931 | 1) | mxs_dma_prep_slave_sg() { 63.218931 | 1) | /* mxs chan ccw idx: 1 */ 63.218932 | 1) 1.750 us | } 63.218933 | 1) 5.875 us | } 63.218934 | 1) | gpmi_chain_command() { 63.218934 | 1) | mxs_dma_prep_slave_sg() { 63.218935 | 1) | /* mxs chan ccw idx: 2 */ 63.218936 | 1) 1.875 us | } 63.218937 | 1) | mxs_dma_prep_slave_sg() { 63.218938 | 1) | /* mxs chan ccw idx: 3 */ 63.218939 | 1) 1.625 us | } 63.218939 | 1) 5.875 us | } 63.218940 | 1) | /* gpmi_chain_wait_ready */ 63.218941 | 1) | mxs_dma_prep_slave_sg() { 63.218942 | 1) | /* mxs chan ccw idx: 4 */ 63.218942 | 1) 1.625 us | } 63.218943 | 1) | /* gpmi_chain_data_read */ 63.218944 | 1) | mxs_dma_prep_slave_sg() { 63.218945 | 1) | /* mxs chan ccw idx: 5 */ 63.218947 | 1) 2.375 us | } 63.218948 | 1) 0.625 us | mxs_dma_tx_submit(); 63.218949 | 1) 1.000 us | mxs_dma_enable_chan(); 63.219276 | 0) 5.125 us | bch_irq(); <---- 63.219283 | 1) | /* jiffies left 250 */ 63.219285 | 1) ! 358.625 us | } 63.219286 | 1) 2.750 us | gpmi_count_bitflips(); 63.219289 | 1) ! 366.000 us | } 63.219290 | 1) | gpmi_ecc_read_page() { 63.219291 | 1) 0.750 us | gpmi_bch_layout_std(); 63.219293 | 1) | gpmi_nfc_exec_op() { 63.219294 | 1) | gpmi_chain_command() { 63.219295 | 1) | mxs_dma_prep_slave_sg() { 63.219295 | 0) 1.875 us | mxs_dma_int_handler(); <---- 63.219296 | 1) | /* mxs chan ccw idx: 6 */ 63.219297 | 1) 2.250 us | } 63.219298 | 1) | mxs_dma_prep_slave_sg() { 63.219298 | 0) 1.000 us | mxs_dma_tasklet(); 63.219299 | 1) | /* mxs chan ccw idx: 0 */ 63.219300 | 1) 1.625 us | } 63.219300 | 1) 6.375 us | } 63.219301 | 1) | gpmi_chain_command() { 63.219302 | 1) | mxs_dma_prep_slave_sg() { 63.219303 | 1) | /* mxs chan ccw idx: 1 */ 63.219304 | 1) 1.625 us | } 63.219305 | 1) | mxs_dma_prep_slave_sg() { 63.219306 | 1) | /* mxs chan ccw idx: 2 */ 63.219306 | 1) 1.875 us | } 63.219307 | 1) 6.000 us | } 63.219308 | 1) | /* gpmi_chain_wait_ready */ 63.219308 | 1) | mxs_dma_prep_slave_sg() { 63.219309 | 1) | /* mxs chan ccw idx: 3 */ 63.219310 | 1) 2.000 us | } 63.219311 | 1) | /* gpmi_chain_data_read */ 63.219312 | 1) | mxs_dma_prep_slave_sg() { 63.219313 | 1) | /* mxs chan ccw idx: 4 */ 63.219314 | 1) 1.750 us | } 63.219315 | 1) 0.625 us | mxs_dma_tx_submit(); 63.219316 | 1) 0.875 us | mxs_dma_enable_chan(); 64.224227 | 1) | /* jiffies left 0 */ In the first gpmi_nfc_exec_op, bch_irq comes first and gpmi_nfc_exec_op exits, but DMA IRQ still not happened yet until the middle of following gpmi_nfc_exec_op, the first DMA transfer index get messed and DMA get timeout. To fix the issue, when there is bch ops in DMA chain, the gpmi_nfc_exec_op should wait for both completions rather than bch completion only. Fixes: ef347c0cfd61 ("mtd: rawnand: gpmi: Implement exec_op") Signed-off-by: Han Xu <han.xu@nxp.com> Reviewed-by: Sascha Hauer <s.hauer@pengutronix.de> --- drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c | 30 +++++++++++++++------- 1 file changed, 21 insertions(+), 9 deletions(-) diff --git a/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c b/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c index b06e202cdd0d..aaae000f9169 100644 --- a/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c +++ b/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c @@ -2256,7 +2256,7 @@ static int gpmi_nfc_exec_op(struct nand_chip *chip, void *buf_read = NULL; const void *buf_write = NULL; bool direct = false; - struct completion *completion; + struct completion *dma_completion, *bch_completion; unsigned long to; if (check_only) @@ -2353,22 +2353,24 @@ static int gpmi_nfc_exec_op(struct nand_chip *chip, this->resources.bch_regs + HW_BCH_FLASH0LAYOUT1); } + desc->callback = dma_irq_callback; + desc->callback_param = this; + dma_completion = &this->dma_done; + bch_completion = NULL; + + init_completion(dma_completion); + if (this->bch && buf_read) { writel(BM_BCH_CTRL_COMPLETE_IRQ_EN, this->resources.bch_regs + HW_BCH_CTRL_SET); - completion = &this->bch_done; - } else { - desc->callback = dma_irq_callback; - desc->callback_param = this; - completion = &this->dma_done; + bch_completion = &this->bch_done; + init_completion(bch_completion); } - init_completion(completion); - dmaengine_submit(desc); dma_async_issue_pending(get_dma_chan(this)); - to = wait_for_completion_timeout(completion, msecs_to_jiffies(1000)); + to = wait_for_completion_timeout(dma_completion, msecs_to_jiffies(1000)); if (!to) { dev_err(this->dev, "DMA timeout, last DMA\n"); gpmi_dump_info(this); @@ -2376,6 +2378,16 @@ static int gpmi_nfc_exec_op(struct nand_chip *chip, goto unmap; } + if (this->bch && buf_read) { + to = wait_for_completion_timeout(bch_completion, msecs_to_jiffies(1000)); + if (!to) { + dev_err(this->dev, "BCH timeout, last DMA\n"); + gpmi_dump_info(this); + ret = -ETIMEDOUT; + goto unmap; + } + } + writel(BM_BCH_CTRL_COMPLETE_IRQ_EN, this->resources.bch_regs + HW_BCH_CTRL_CLR); gpmi_clear_bch(this); -- 2.17.1 ______________________________________________________ Linux MTD discussion mailing list http://lists.infradead.org/mailman/listinfo/linux-mtd/ ^ permalink raw reply related [flat|nested] 7+ messages in thread
* Re: [PATCH v2 2/2] mtd: rawnand: gpmi: Fix the random DMA timeout issue 2020-12-09 3:51 ` [PATCH v2 2/2] mtd: rawnand: gpmi: Fix the random DMA timeout issue Han Xu @ 2020-12-10 21:39 ` Miquel Raynal 0 siblings, 0 replies; 7+ messages in thread From: Miquel Raynal @ 2020-12-10 21:39 UTC (permalink / raw) To: Han Xu, miquel.raynal, s.hauer; +Cc: linux-mtd On Wed, 2020-12-09 at 03:51:04 UTC, Han Xu wrote: > To get better performance, current gpmi driver collected and chained all > small DMA transfers in gpmi_nfc_exec_op, the whole chain triggered and > wait for complete at the end. > > But some random DMA timeout found in this new driver, with the help of > ftrace, we found the root cause is as follows: > > Take gpmi_ecc_read_page() as an example, gpmi_nfc_exec_op collected 6 > DMA transfers and the DMA chain triggered at the end. It waits for bch > completion and check jiffies if it's timeout. The typical function graph > shown below, > > 63.216351 | 1) | gpmi_ecc_read_page() { > 63.216352 | 1) 0.750 us | gpmi_bch_layout_std(); > 63.216354 | 1) | gpmi_nfc_exec_op() { > 63.216355 | 1) | gpmi_chain_command() { > 63.216356 | 1) | mxs_dma_prep_slave_sg() { > 63.216357 | 1) | /* mxs chan ccw idx: 0 */ > 63.216358 | 1) 1.750 us | } > 63.216359 | 1) | mxs_dma_prep_slave_sg() { > 63.216360 | 1) | /* mxs chan ccw idx: 1 */ > 63.216361 | 1) 2.000 us | } > 63.216361 | 1) 6.500 us | } > 63.216362 | 1) | gpmi_chain_command() { > 63.216363 | 1) | mxs_dma_prep_slave_sg() { > 63.216364 | 1) | /* mxs chan ccw idx: 2 */ > 63.216365 | 1) 1.750 us | } > 63.216366 | 1) | mxs_dma_prep_slave_sg() { > 63.216367 | 1) | /* mxs chan ccw idx: 3 */ > 63.216367 | 1) 1.750 us | } > 63.216368 | 1) 5.875 us | } > 63.216369 | 1) | /* gpmi_chain_wait_ready */ > 63.216370 | 1) | mxs_dma_prep_slave_sg() { > 63.216372 | 1) | /* mxs chan ccw idx: 4 */ > 63.216373 | 1) 3.000 us | } > 63.216374 | 1) | /* gpmi_chain_data_read */ > 63.216376 | 1) | mxs_dma_prep_slave_sg() { > 63.216377 | 1) | /* mxs chan ccw idx: 5 */ > 63.216378 | 1) 2.000 us | } > 63.216379 | 1) 1.125 us | mxs_dma_tx_submit(); > 63.216381 | 1) 1.000 us | mxs_dma_enable_chan(); > 63.216712 | 0) 2.625 us | mxs_dma_int_handler(); > 63.216717 | 0) 4.250 us | bch_irq(); > 63.216723 | 0) 1.250 us | mxs_dma_tasklet(); > 63.216723 | 1) | /* jiffies left 250 */ > 63.216725 | 1) ! 372.000 us | } > 63.216726 | 1) 2.625 us | gpmi_count_bitflips(); > 63.216730 | 1) ! 379.125 us | } > > but it's not gurantee that bch irq handled always after dma irq handled, > sometimes bch_irq comes first and gpmi_nfc_exec_op won't wait anymore, > another gpmi_nfc_exec_op may get invoked before last DMA chain IRQ > handled, this messed up the next DMA chain and causes DMA timeout. Check > the trace log when issue happened. > > 63.218923 | 1) | gpmi_ecc_read_page() { > 63.218924 | 1) 0.625 us | gpmi_bch_layout_std(); > 63.218926 | 1) | gpmi_nfc_exec_op() { > 63.218927 | 1) | gpmi_chain_command() { > 63.218928 | 1) | mxs_dma_prep_slave_sg() { > 63.218929 | 1) | /* mxs chan ccw idx: 0 */ > 63.218929 | 1) 1.625 us | } > 63.218931 | 1) | mxs_dma_prep_slave_sg() { > 63.218931 | 1) | /* mxs chan ccw idx: 1 */ > 63.218932 | 1) 1.750 us | } > 63.218933 | 1) 5.875 us | } > 63.218934 | 1) | gpmi_chain_command() { > 63.218934 | 1) | mxs_dma_prep_slave_sg() { > 63.218935 | 1) | /* mxs chan ccw idx: 2 */ > 63.218936 | 1) 1.875 us | } > 63.218937 | 1) | mxs_dma_prep_slave_sg() { > 63.218938 | 1) | /* mxs chan ccw idx: 3 */ > 63.218939 | 1) 1.625 us | } > 63.218939 | 1) 5.875 us | } > 63.218940 | 1) | /* gpmi_chain_wait_ready */ > 63.218941 | 1) | mxs_dma_prep_slave_sg() { > 63.218942 | 1) | /* mxs chan ccw idx: 4 */ > 63.218942 | 1) 1.625 us | } > 63.218943 | 1) | /* gpmi_chain_data_read */ > 63.218944 | 1) | mxs_dma_prep_slave_sg() { > 63.218945 | 1) | /* mxs chan ccw idx: 5 */ > 63.218947 | 1) 2.375 us | } > 63.218948 | 1) 0.625 us | mxs_dma_tx_submit(); > 63.218949 | 1) 1.000 us | mxs_dma_enable_chan(); > 63.219276 | 0) 5.125 us | bch_irq(); <---- > 63.219283 | 1) | /* jiffies left 250 */ > 63.219285 | 1) ! 358.625 us | } > 63.219286 | 1) 2.750 us | gpmi_count_bitflips(); > 63.219289 | 1) ! 366.000 us | } > 63.219290 | 1) | gpmi_ecc_read_page() { > 63.219291 | 1) 0.750 us | gpmi_bch_layout_std(); > 63.219293 | 1) | gpmi_nfc_exec_op() { > 63.219294 | 1) | gpmi_chain_command() { > 63.219295 | 1) | mxs_dma_prep_slave_sg() { > 63.219295 | 0) 1.875 us | mxs_dma_int_handler(); <---- > 63.219296 | 1) | /* mxs chan ccw idx: 6 */ > 63.219297 | 1) 2.250 us | } > 63.219298 | 1) | mxs_dma_prep_slave_sg() { > 63.219298 | 0) 1.000 us | mxs_dma_tasklet(); > 63.219299 | 1) | /* mxs chan ccw idx: 0 */ > 63.219300 | 1) 1.625 us | } > 63.219300 | 1) 6.375 us | } > 63.219301 | 1) | gpmi_chain_command() { > 63.219302 | 1) | mxs_dma_prep_slave_sg() { > 63.219303 | 1) | /* mxs chan ccw idx: 1 */ > 63.219304 | 1) 1.625 us | } > 63.219305 | 1) | mxs_dma_prep_slave_sg() { > 63.219306 | 1) | /* mxs chan ccw idx: 2 */ > 63.219306 | 1) 1.875 us | } > 63.219307 | 1) 6.000 us | } > 63.219308 | 1) | /* gpmi_chain_wait_ready */ > 63.219308 | 1) | mxs_dma_prep_slave_sg() { > 63.219309 | 1) | /* mxs chan ccw idx: 3 */ > 63.219310 | 1) 2.000 us | } > 63.219311 | 1) | /* gpmi_chain_data_read */ > 63.219312 | 1) | mxs_dma_prep_slave_sg() { > 63.219313 | 1) | /* mxs chan ccw idx: 4 */ > 63.219314 | 1) 1.750 us | } > 63.219315 | 1) 0.625 us | mxs_dma_tx_submit(); > 63.219316 | 1) 0.875 us | mxs_dma_enable_chan(); > 64.224227 | 1) | /* jiffies left 0 */ > > In the first gpmi_nfc_exec_op, bch_irq comes first and gpmi_nfc_exec_op > exits, but DMA IRQ still not happened yet until the middle of following > gpmi_nfc_exec_op, the first DMA transfer index get messed and DMA get > timeout. > > To fix the issue, when there is bch ops in DMA chain, the > gpmi_nfc_exec_op should wait for both completions rather than bch > completion only. > > Fixes: ef347c0cfd61 ("mtd: rawnand: gpmi: Implement exec_op") > Signed-off-by: Han Xu <han.xu@nxp.com> > Reviewed-by: Sascha Hauer <s.hauer@pengutronix.de> Applied to https://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux.git 1406495, thanks. Miquel ______________________________________________________ Linux MTD discussion mailing list http://lists.infradead.org/mailman/listinfo/linux-mtd/ ^ permalink raw reply [flat|nested] 7+ messages in thread
end of thread, other threads:[~2020-12-10 21:40 UTC | newest] Thread overview: 7+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2020-12-09 3:51 [PATCH v2 0/2] fix some gpmi nand driver bugs Han Xu 2020-12-09 3:51 ` [PATCH v2 1/2] mtd: rawnand: gpmi: Fix the driver only sense CS0 R/B issue Han Xu 2020-12-10 9:45 ` Sascha Hauer 2020-12-10 9:54 ` Fabio Estevam 2020-12-10 21:39 ` Miquel Raynal 2020-12-09 3:51 ` [PATCH v2 2/2] mtd: rawnand: gpmi: Fix the random DMA timeout issue Han Xu 2020-12-10 21:39 ` Miquel Raynal
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