From: Apurva Nandan <a-nandan@ti.com> To: Miquel Raynal <miquel.raynal@bootlin.com> Cc: Richard Weinberger <richard@nod.at>, Vignesh Raghavendra <vigneshr@ti.com>, Mark Brown <broonie@kernel.org>, Patrice Chotard <patrice.chotard@foss.st.com>, Boris Brezillon <boris.brezillon@collabora.com>, <linux-mtd@lists.infradead.org>, <linux-kernel@vger.kernel.org>, <linux-spi@vger.kernel.org>, Pratyush Yadav <p.yadav@ti.com> Subject: Re: [PATCH 12/13] mtd: spinand: Perform Power-on-Reset when runtime_pm suspend is issued Date: Fri, 20 Aug 2021 17:15:38 +0530 [thread overview] Message-ID: <2437d7b9-2a01-28c7-9a81-f38c35f37964@ti.com> (raw) In-Reply-To: <20210806211231.5c569939@xps13> On 07/08/21 12:42 am, Miquel Raynal wrote: > Hi Apurva, > > Apurva Nandan <a-nandan@ti.com> wrote on Tue, 13 Jul 2021 13:05:37 > +0000: > >> A soft reset using FFh command doesn't erase the flash's configuration >> and doesn't reset the SPI IO mode also. This can result in the flash >> being in a different SPI IO mode, e.g. Octal DTR, when resuming from >> sleep. This would render the flash in an unusable state. > > could put the falsh in? > Okay, will make it clearer. Basically, we don't want the flash to be in an ambiguous state. It might or might not have undergone a power off during the suspend state. So, the spinand core wouldn't know if the flash is still in Octal DTR mode or not. If it is still in Octal DTR mode, then none of the SPI instruction during mtd_resume() would work. So this is an ambiguous situation for driver. To avoid this, perform a PoR reset before suspending. >> Perform a Power-on-Reset (PoR), if available in the flash, when >> suspending the device by runtime_pm. This would set the flash to clean > > I think runtime_pm is something else. > Yeah, will make it clearer. >> state for reinitialization during resume and would also ensure that it >> is in standard SPI IO mode (1S-1S-1S) before the resume begins. > > Please add a comment about this to explain why we don't do this reset > at resume time. > Yes sure! >> >> Signed-off-by: Apurva Nandan <a-nandan@ti.com> >> --- >> drivers/mtd/nand/spi/core.c | 16 ++++++++++++++++ >> 1 file changed, 16 insertions(+) >> >> diff --git a/drivers/mtd/nand/spi/core.c b/drivers/mtd/nand/spi/core.c >> index 608f4eb85b0a..6fb3aa6af540 100644 >> --- a/drivers/mtd/nand/spi/core.c >> +++ b/drivers/mtd/nand/spi/core.c >> @@ -1329,6 +1329,21 @@ static void spinand_mtd_resume(struct mtd_info *mtd) >> spinand_ecc_enable(spinand, false); >> } >> >> +static int spinand_mtd_suspend(struct mtd_info *mtd) >> +{ >> + struct spinand_device *spinand = mtd_to_spinand(mtd); >> + int ret; >> + >> + if (!(spinand->flags & SPINAND_HAS_POR_CMD_BIT)) >> + return 0; >> + >> + ret = spinand_power_on_rst_op(spinand); >> + if (ret) >> + dev_err(&spinand->spimem->spi->dev, "suspend() failed\n"); >> + >> + return ret; >> +} >> + >> static int spinand_init(struct spinand_device *spinand) >> { >> struct device *dev = &spinand->spimem->spi->dev; >> @@ -1401,6 +1416,7 @@ static int spinand_init(struct spinand_device *spinand) >> mtd->_erase = spinand_mtd_erase; >> mtd->_max_bad_blocks = nanddev_mtd_max_bad_blocks; >> mtd->_resume = spinand_mtd_resume; >> + mtd->_suspend = spinand_mtd_suspend; >> >> if (nand->ecc.engine) { >> ret = mtd_ooblayout_count_freebytes(mtd); > > > Thanks, > Miquèl > > ______________________________________________________ > Linux MTD discussion mailing list > http://lists.infradead.org/mailman/listinfo/linux-mtd/ > Thanks, Apurva Nandan
WARNING: multiple messages have this Message-ID (diff)
From: Apurva Nandan <a-nandan@ti.com> To: Miquel Raynal <miquel.raynal@bootlin.com> Cc: Richard Weinberger <richard@nod.at>, Vignesh Raghavendra <vigneshr@ti.com>, Mark Brown <broonie@kernel.org>, Patrice Chotard <patrice.chotard@foss.st.com>, Boris Brezillon <boris.brezillon@collabora.com>, <linux-mtd@lists.infradead.org>, <linux-kernel@vger.kernel.org>, <linux-spi@vger.kernel.org>, Pratyush Yadav <p.yadav@ti.com> Subject: Re: [PATCH 12/13] mtd: spinand: Perform Power-on-Reset when runtime_pm suspend is issued Date: Fri, 20 Aug 2021 17:15:38 +0530 [thread overview] Message-ID: <2437d7b9-2a01-28c7-9a81-f38c35f37964@ti.com> (raw) In-Reply-To: <20210806211231.5c569939@xps13> On 07/08/21 12:42 am, Miquel Raynal wrote: > Hi Apurva, > > Apurva Nandan <a-nandan@ti.com> wrote on Tue, 13 Jul 2021 13:05:37 > +0000: > >> A soft reset using FFh command doesn't erase the flash's configuration >> and doesn't reset the SPI IO mode also. This can result in the flash >> being in a different SPI IO mode, e.g. Octal DTR, when resuming from >> sleep. This would render the flash in an unusable state. > > could put the falsh in? > Okay, will make it clearer. Basically, we don't want the flash to be in an ambiguous state. It might or might not have undergone a power off during the suspend state. So, the spinand core wouldn't know if the flash is still in Octal DTR mode or not. If it is still in Octal DTR mode, then none of the SPI instruction during mtd_resume() would work. So this is an ambiguous situation for driver. To avoid this, perform a PoR reset before suspending. >> Perform a Power-on-Reset (PoR), if available in the flash, when >> suspending the device by runtime_pm. This would set the flash to clean > > I think runtime_pm is something else. > Yeah, will make it clearer. >> state for reinitialization during resume and would also ensure that it >> is in standard SPI IO mode (1S-1S-1S) before the resume begins. > > Please add a comment about this to explain why we don't do this reset > at resume time. > Yes sure! >> >> Signed-off-by: Apurva Nandan <a-nandan@ti.com> >> --- >> drivers/mtd/nand/spi/core.c | 16 ++++++++++++++++ >> 1 file changed, 16 insertions(+) >> >> diff --git a/drivers/mtd/nand/spi/core.c b/drivers/mtd/nand/spi/core.c >> index 608f4eb85b0a..6fb3aa6af540 100644 >> --- a/drivers/mtd/nand/spi/core.c >> +++ b/drivers/mtd/nand/spi/core.c >> @@ -1329,6 +1329,21 @@ static void spinand_mtd_resume(struct mtd_info *mtd) >> spinand_ecc_enable(spinand, false); >> } >> >> +static int spinand_mtd_suspend(struct mtd_info *mtd) >> +{ >> + struct spinand_device *spinand = mtd_to_spinand(mtd); >> + int ret; >> + >> + if (!(spinand->flags & SPINAND_HAS_POR_CMD_BIT)) >> + return 0; >> + >> + ret = spinand_power_on_rst_op(spinand); >> + if (ret) >> + dev_err(&spinand->spimem->spi->dev, "suspend() failed\n"); >> + >> + return ret; >> +} >> + >> static int spinand_init(struct spinand_device *spinand) >> { >> struct device *dev = &spinand->spimem->spi->dev; >> @@ -1401,6 +1416,7 @@ static int spinand_init(struct spinand_device *spinand) >> mtd->_erase = spinand_mtd_erase; >> mtd->_max_bad_blocks = nanddev_mtd_max_bad_blocks; >> mtd->_resume = spinand_mtd_resume; >> + mtd->_suspend = spinand_mtd_suspend; >> >> if (nand->ecc.engine) { >> ret = mtd_ooblayout_count_freebytes(mtd); > > > Thanks, > Miquèl > > ______________________________________________________ > Linux MTD discussion mailing list > http://lists.infradead.org/mailman/listinfo/linux-mtd/ > Thanks, Apurva Nandan ______________________________________________________ Linux MTD discussion mailing list http://lists.infradead.org/mailman/listinfo/linux-mtd/
next prev parent reply other threads:[~2021-08-20 11:46 UTC|newest] Thread overview: 102+ messages / expand[flat|nested] mbox.gz Atom feed top 2021-07-13 13:05 [PATCH 00/13] mtd: spinand: Add Octal DTR SPI (8D-8D-8D) mode support Apurva Nandan 2021-07-13 13:05 ` Apurva Nandan 2021-07-13 13:05 ` [PATCH 01/13] spi: spi-mem: Add DTR templates for cmd, address, dummy and data phase Apurva Nandan 2021-07-13 13:05 ` Apurva Nandan 2021-07-14 17:06 ` Mark Brown 2021-07-14 17:06 ` Mark Brown 2021-08-23 7:57 ` Boris Brezillon 2021-08-23 7:57 ` Boris Brezillon 2021-07-13 13:05 ` [PATCH 02/13] mtd: spinand: Add enum spinand_proto to indicate current SPI IO mode Apurva Nandan 2021-07-13 13:05 ` Apurva Nandan 2021-07-13 13:05 ` [PATCH 03/13] mtd: spinand: Setup spi_mem_op for the SPI IO protocol using reg_proto Apurva Nandan 2021-07-13 13:05 ` Apurva Nandan 2021-08-06 18:30 ` Miquel Raynal 2021-08-06 18:30 ` Miquel Raynal 2021-08-20 9:52 ` Apurva Nandan 2021-08-20 9:52 ` Apurva Nandan 2021-08-20 12:08 ` Miquel Raynal 2021-08-20 12:08 ` Miquel Raynal 2021-08-23 7:11 ` Boris Brezillon 2021-08-23 7:11 ` Boris Brezillon 2021-08-23 7:24 ` Miquel Raynal 2021-08-23 7:24 ` Miquel Raynal 2021-07-13 13:05 ` [PATCH 04/13] mtd: spinand: Fix odd byte addr and data phase in read/write reg op and write VCR op for Octal DTR mode Apurva Nandan 2021-07-13 13:05 ` Apurva Nandan 2021-08-06 18:43 ` Miquel Raynal 2021-08-06 18:43 ` Miquel Raynal 2021-08-20 10:27 ` Apurva Nandan 2021-08-20 10:27 ` Apurva Nandan 2021-08-20 12:06 ` Miquel Raynal 2021-08-20 12:06 ` Miquel Raynal 2021-07-13 13:05 ` [PATCH 05/13] mtd: spinand: Add adjust_op() in manufacturer_ops to modify the ops for manufacturer specific changes Apurva Nandan 2021-07-13 13:05 ` Apurva Nandan 2021-07-13 13:05 ` [PATCH 06/13] mtd: spinand: Add macros for Octal DTR page read and write operations Apurva Nandan 2021-07-13 13:05 ` Apurva Nandan 2021-08-06 18:54 ` Miquel Raynal 2021-08-06 18:54 ` Miquel Raynal 2021-08-20 10:35 ` Apurva Nandan 2021-08-20 10:35 ` Apurva Nandan 2021-07-13 13:05 ` [PATCH 07/13] mtd: spinand: Allow enabling Octal DTR mode in the core Apurva Nandan 2021-07-13 13:05 ` Apurva Nandan 2021-08-06 18:58 ` Miquel Raynal 2021-08-06 18:58 ` Miquel Raynal 2021-08-20 10:41 ` Apurva Nandan 2021-08-20 10:41 ` Apurva Nandan 2021-07-13 13:05 ` [PATCH 08/13] mtd: spinand: Reject 8D-8D-8D op_templates if octal_dtr_enale() is missing in manufacturer_op Apurva Nandan 2021-07-13 13:05 ` Apurva Nandan 2021-08-06 19:01 ` Miquel Raynal 2021-08-06 19:01 ` Miquel Raynal 2021-08-20 11:26 ` Apurva Nandan 2021-08-20 11:26 ` Apurva Nandan 2021-08-20 12:14 ` Miquel Raynal 2021-08-20 12:14 ` Miquel Raynal 2021-08-20 13:54 ` Apurva Nandan 2021-08-20 13:54 ` Apurva Nandan 2021-08-20 14:38 ` Miquel Raynal 2021-08-20 14:38 ` Miquel Raynal 2021-08-20 15:53 ` Apurva Nandan 2021-08-20 15:53 ` Apurva Nandan 2021-07-13 13:05 ` [PATCH 09/13] mtd: spinand: Add support for write volatile configuration register op Apurva Nandan 2021-07-13 13:05 ` Apurva Nandan 2021-08-06 19:05 ` Miquel Raynal 2021-08-06 19:05 ` Miquel Raynal 2021-08-20 11:30 ` Apurva Nandan 2021-08-20 11:30 ` Apurva Nandan 2021-07-13 13:05 ` [PATCH 10/13] mtd: spinand: Add octal_dtr_enable() for Winbond manufacturer_ops Apurva Nandan 2021-07-13 13:05 ` Apurva Nandan 2021-08-06 19:06 ` Miquel Raynal 2021-08-06 19:06 ` Miquel Raynal 2021-08-20 11:31 ` Apurva Nandan 2021-08-20 11:31 ` Apurva Nandan 2021-07-13 13:05 ` [PATCH 11/13] mtd: spinand: Add support for Power-on-Reset (PoR) instruction Apurva Nandan 2021-07-13 13:05 ` Apurva Nandan 2021-08-06 19:08 ` Miquel Raynal 2021-08-06 19:08 ` Miquel Raynal 2021-08-20 11:39 ` Apurva Nandan 2021-08-20 11:39 ` Apurva Nandan 2021-08-20 12:18 ` Miquel Raynal 2021-08-20 12:18 ` Miquel Raynal 2021-08-20 13:41 ` Apurva Nandan 2021-08-20 13:41 ` Apurva Nandan 2021-08-20 14:17 ` Miquel Raynal 2021-08-20 14:17 ` Miquel Raynal 2021-08-20 15:56 ` Apurva Nandan 2021-08-20 15:56 ` Apurva Nandan 2021-07-13 13:05 ` [PATCH 12/13] mtd: spinand: Perform Power-on-Reset when runtime_pm suspend is issued Apurva Nandan 2021-07-13 13:05 ` Apurva Nandan 2021-08-06 19:12 ` Miquel Raynal 2021-08-06 19:12 ` Miquel Raynal 2021-08-20 11:45 ` Apurva Nandan [this message] 2021-08-20 11:45 ` Apurva Nandan 2021-07-13 13:05 ` [PATCH 13/13] mtd: spinand: Add support for Winbond W35N01JW SPI NAND flash Apurva Nandan 2021-07-13 13:05 ` Apurva Nandan 2021-08-06 19:14 ` Miquel Raynal 2021-08-06 19:14 ` Miquel Raynal 2021-08-20 11:51 ` Apurva Nandan 2021-08-20 11:51 ` Apurva Nandan 2021-08-20 12:02 ` Miquel Raynal 2021-08-20 12:02 ` Miquel Raynal 2021-08-20 13:14 ` Apurva Nandan 2021-08-20 13:14 ` Apurva Nandan 2021-07-20 16:53 ` [PATCH 00/13] mtd: spinand: Add Octal DTR SPI (8D-8D-8D) mode support Nandan, Apurva 2021-07-20 16:53 ` Nandan, Apurva
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=2437d7b9-2a01-28c7-9a81-f38c35f37964@ti.com \ --to=a-nandan@ti.com \ --cc=boris.brezillon@collabora.com \ --cc=broonie@kernel.org \ --cc=linux-kernel@vger.kernel.org \ --cc=linux-mtd@lists.infradead.org \ --cc=linux-spi@vger.kernel.org \ --cc=miquel.raynal@bootlin.com \ --cc=p.yadav@ti.com \ --cc=patrice.chotard@foss.st.com \ --cc=richard@nod.at \ --cc=vigneshr@ti.com \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.