> -----Original Message-----
> From: Vivi, Rodrigo <rodrigo.vivi@xxxxxxxxx>
> Sent: Wednesday, January 29, 2025 11:51 PM
> To: Usyskin, Alexander <alexander.usyskin@xxxxxxxxx>
> Cc: Miquel Raynal <miquel.raynal@xxxxxxxxxxx>; Richard Weinberger
> <richard@xxxxxx>; Vignesh Raghavendra <vigneshr@xxxxxx>; De Marchi,
> Lucas <lucas.demarchi@xxxxxxxxx>; Thomas Hellström
> <thomas.hellstrom@xxxxxxxxxxxxxxx>; Maarten Lankhorst
> <maarten.lankhorst@xxxxxxxxxxxxxxx>; Maxime Ripard
> <mripard@xxxxxxxxxx>; Thomas Zimmermann <tzimmermann@xxxxxxx>;
> David Airlie <airlied@xxxxxxxxx>; Simona Vetter <simona@xxxxxxxx>; Jani
> Nikula <jani.nikula@xxxxxxxxxxxxxxx>; Joonas Lahtinen
> <joonas.lahtinen@xxxxxxxxxxxxxxx>; Tvrtko Ursulin <tursulin@xxxxxxxxxxx>;
> Poosa, Karthik <karthik.poosa@xxxxxxxxx>; Abliyev, Reuven
> <reuven.abliyev@xxxxxxxxx>; Weil, Oren jer <oren.jer.weil@xxxxxxxxx>; linux-
> mtd@xxxxxxxxxxxxxxxxxxx; dri-devel@xxxxxxxxxxxxxxxxxxxxx; intel-
> gfx@xxxxxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
> Subject: Re: [PATCH v4 07/11] mtd: intel-dg: wake card on operations
>
> On Wed, Jan 01, 2025 at 05:39:21PM +0200, Alexander Usyskin wrote:
> > Enable runtime PM in mtd driver to notify graphics driver that
> > whole card should be kept awake while nvm operations are
> > performed through this driver.
> >
> > CC: Lucas De Marchi <lucas.demarchi@xxxxxxxxx>
> > Acked-by: Miquel Raynal <miquel.raynal@xxxxxxxxxxx>
> > Signed-off-by: Alexander Usyskin <alexander.usyskin@xxxxxxxxx>
> > ---
> > drivers/mtd/devices/mtd-intel-dg.c | 79 +++++++++++++++++++++++++-----
> > 1 file changed, 67 insertions(+), 12 deletions(-)
> >
> > diff --git a/drivers/mtd/devices/mtd-intel-dg.c b/drivers/mtd/devices/mtd-
> intel-dg.c
> > index 230bf444b7fe..a84153812291 100644
> > --- a/drivers/mtd/devices/mtd-intel-dg.c
> > +++ b/drivers/mtd/devices/mtd-intel-dg.c
> > @@ -15,11 +15,14 @@
> > #include <linux/module.h>
> > #include <linux/mtd/mtd.h>
> > #include <linux/mtd/partitions.h>
> > +#include <linux/pm_runtime.h>
> > #include <linux/string.h>
> > #include <linux/slab.h>
> > #include <linux/sizes.h>
> > #include <linux/types.h>
> >
> > +#define INTEL_DG_NVM_RPM_TIMEOUT 500
> > +
> > struct intel_dg_nvm {
> > struct kref refcnt;
> > struct mtd_info mtd;
> > @@ -460,6 +463,7 @@ static int intel_dg_mtd_erase(struct mtd_info *mtd,
> struct erase_info *info)
> > loff_t from;
> > size_t len;
> > size_t total_len;
> > + int ret = 0;
> >
> > if (WARN_ON(!nvm))
> > return -EINVAL;
> > @@ -474,20 +478,28 @@ static int intel_dg_mtd_erase(struct mtd_info
> *mtd, struct erase_info *info)
> > total_len = info->len;
> > addr = info->addr;
> >
> > + ret = pm_runtime_resume_and_get(&mtd->dev);
>
> I'm glad we are not accessing the parent directly here anymore,
> but to me it is still strange.
> I feel that we should be using &aux_dev->dev; instead of mtd->dev.
>
> What am I missing?
>
aux_dev->dev is the parent device stored in mtd->dev->parent
When in previous version I access mtd->dev->parent, I actually access aux_dev->dev.
Now we have real mtd master drevice and can rely on it runtime_pm.
> > + if (ret < 0) {
> > + dev_err(&mtd->dev, "rpm: get failed %d\n", ret);
> > + return ret;
> > + }
> > +
> > guard(mutex)(&nvm->lock);
> >
> > while (total_len > 0) {
> > if (!IS_ALIGNED(addr, SZ_4K) || !IS_ALIGNED(total_len,
> SZ_4K)) {
> > dev_err(&mtd->dev, "unaligned erase %llx %zx\n",
> addr, total_len);
> > info->fail_addr = addr;
> > - return -ERANGE;
> > + ret = -ERANGE;
> > + goto out;
> > }
> >
> > idx = idg_nvm_get_region(nvm, addr);
> > if (idx >= nvm->nregions) {
> > dev_err(&mtd->dev, "out of range");
> > info->fail_addr = MTD_FAIL_ADDR_UNKNOWN;
> > - return -ERANGE;
> > + ret = -ERANGE;
> > + goto out;
> > }
> >
> > from = addr - nvm->regions[idx].offset;
> > @@ -503,14 +515,18 @@ static int intel_dg_mtd_erase(struct mtd_info
> *mtd, struct erase_info *info)
> > if (bytes < 0) {
> > dev_dbg(&mtd->dev, "erase failed with %zd\n",
> bytes);
> > info->fail_addr += nvm->regions[idx].offset;
> > - return bytes;
> > + ret = bytes;
> > + goto out;
> > }
> >
> > addr += len;
> > total_len -= len;
> > }
> >
> > - return 0;
> > +out:
> > + pm_runtime_mark_last_busy(&mtd->dev);
> > + pm_runtime_put_autosuspend(&mtd->dev);
> > + return ret;
> > }
> >
> > static int intel_dg_mtd_read(struct mtd_info *mtd, loff_t from, size_t len,
> > @@ -539,17 +555,25 @@ static int intel_dg_mtd_read(struct mtd_info *mtd,
> loff_t from, size_t len,
> > if (len > nvm->regions[idx].size - from)
> > len = nvm->regions[idx].size - from;
> >
> > + ret = pm_runtime_resume_and_get(&mtd->dev);
> > + if (ret < 0) {
> > + dev_err(&mtd->dev, "rpm: get failed %zd\n", ret);
> > + return ret;
> > + }
> > +
> > guard(mutex)(&nvm->lock);
> >
> > ret = idg_read(nvm, region, from, len, buf);
> > if (ret < 0) {
> > dev_dbg(&mtd->dev, "read failed with %zd\n", ret);
> > - return ret;
> > + } else {
> > + *retlen = ret;
> > + ret = 0;
> > }
> >
> > - *retlen = ret;
> > -
> > - return 0;
> > + pm_runtime_mark_last_busy(&mtd->dev);
> > + pm_runtime_put_autosuspend(&mtd->dev);
> > + return ret;
> > }
> >
> > static int intel_dg_mtd_write(struct mtd_info *mtd, loff_t to, size_t len,
> > @@ -578,17 +602,25 @@ static int intel_dg_mtd_write(struct mtd_info
> *mtd, loff_t to, size_t len,
> > if (len > nvm->regions[idx].size - to)
> > len = nvm->regions[idx].size - to;
> >
> > + ret = pm_runtime_resume_and_get(&mtd->dev);
> > + if (ret < 0) {
> > + dev_err(&mtd->dev, "rpm: get failed %zd\n", ret);
> > + return ret;
> > + }
> > +
> > guard(mutex)(&nvm->lock);
> >
> > ret = idg_write(nvm, region, to, len, buf);
> > if (ret < 0) {
> > dev_dbg(&mtd->dev, "write failed with %zd\n", ret);
> > - return ret;
> > + } else {
> > + *retlen = ret;
> > + ret = 0;
> > }
> >
> > - *retlen = ret;
> > -
> > - return 0;
> > + pm_runtime_mark_last_busy(&mtd->dev);
> > + pm_runtime_put_autosuspend(&mtd->dev);
> > + return ret;
> > }
> >
> > static void intel_dg_nvm_release(struct kref *kref)
> > @@ -670,6 +702,15 @@ static int intel_dg_nvm_init_mtd(struct
> intel_dg_nvm *nvm, struct device *device
> >
> > kfree(parts);
> >
> > + if (ret)
> > + goto out;
> > +
> > + devm_pm_runtime_enable(&nvm->mtd.dev);
> > +
> > + pm_runtime_set_autosuspend_delay(&nvm->mtd.dev,
> INTEL_DG_NVM_RPM_TIMEOUT);
> > + pm_runtime_use_autosuspend(&nvm->mtd.dev);
> > +
> > +out:
> > return ret;
> > }
> >
> > @@ -720,6 +761,17 @@ static int intel_dg_mtd_probe(struct
> auxiliary_device *aux_dev,
> > n++;
> > }
> >
> > + devm_pm_runtime_enable(device);
> > +
> > + pm_runtime_set_autosuspend_delay(device,
> INTEL_DG_NVM_RPM_TIMEOUT);
> > + pm_runtime_use_autosuspend(device);
> > +
> > + ret = pm_runtime_resume_and_get(device);
> > + if (ret < 0) {
> > + dev_err(device, "rpm: get failed %d\n", ret);
> > + goto err_norpm;
> > + }
> > +
> > nvm->base = devm_ioremap_resource(device, &invm->bar);
> > if (IS_ERR(nvm->base)) {
> > dev_err(device, "mmio not mapped\n");
> > @@ -742,9 +794,12 @@ static int intel_dg_mtd_probe(struct
> auxiliary_device *aux_dev,
> >
> > dev_set_drvdata(&aux_dev->dev, nvm);
> >
> > + pm_runtime_put(device);
> > return 0;
> >
> > err:
> > + pm_runtime_put(device);
> > +err_norpm:
> > kref_put(&nvm->refcnt, intel_dg_nvm_release);
> > return ret;
> > }
> > --
> > 2.43.0
> >
