[PATCH v6 00/12] Add suspend to ram support for PCIe on J7200

[PATCH v6 00/12] Add suspend to ram support for PCIe on J7200

[Thomas Richard]

This adds suspend to ram support for the PCIe (RC mode) on J7200 platform.

This 6th iteration fixes a compile issue in the i2c-omap driver if
CONFIG_PM_SLEEP is not set.
A new patch was added to remove the __maybe_unused attribute of
omap_i2c_runtime_suspend() and omap_i2c_runtime_resume().

Regards,

Thomas

Signed-off-by: Thomas Richard <thomas.richard@bootlin.com>
---
Changes in v6:
- i2c-omap: add a patch to remove __maybe_unused attribute of
  omap_i2c_runtime_suspend() and omap_i2c_runtime_resume()
- i2c-omap: fix compile issue if CONFIG_PM_SLEEP is not set
- Link to v5: https://lore.kernel.org/r/20240102-j7200-pcie-s2r-v5-0-4b8c46711ded@bootlin.com

Changes in v5:
- all: series rebased on Linux 6.9-rc1
- pinctrl-single: patch removed (already applied to the pinctrl tree)
- phy: patches moved to a dedicated series.
- pci: add T_PERST_CLK_US macro.
- pci-j721e: update the comments about T_PERST_CLK_US.
- Link to v4: https://lore.kernel.org/r/20240102-j7200-pcie-s2r-v4-0-6f1f53390c85@bootlin.com

Changes in v4:
- all: use SoB/Co-developed-by for patches initially developed by Théo
  Lebrun.
- pinctrl-single: squash the two commits.
- i2c-omap: fix line lenghts of the comment in omap_i2c_suspend().
- mux: mux_chip_resume() return 0 or at the first error.
- phy-j721e-wiz: clean code around dev_err_probe().
- phy-j721e-wiz: use REF_CLK_100MHZ macros.
- pci: fix subject line for all PCI patches.
- pci-cadence: use fsleep() instead of usleep_range().
- pci-cadence: remove cdns_torrent_clk_cleanup() call in
  cdns_torrent_phy_resume_noirq().
- pci-j721e: add a patch to use dev_err_probe() instead of dev_err() in the probe().
- pci-j721e: fix unordered header files.
- pci-j721e: remove some log spammers.
- pci-j721e: add a missing clock disable in j721e_pcie_resume_noirq().
- pci-j721e: simplify the patch "Add reset GPIO to struct j721e_pcie"
- Link to v3: https://lore.kernel.org/r/20240102-j7200-pcie-s2r-v3-0-5c2e4a3fac1f@bootlin.com

Changes in v3:
- pinctrl-single: split patch in two parts, a first patch to remove the
  dead code, a second to move suspend()/resume() callbacks to noirq.
- i2c-omap: add a comments above the suspend_noirq() callback.
- mux: now mux_chip_resume() try to restores all muxes, then return 0 if
  all is ok or the first failure.
- mmio: fix commit message.
- phy-j721e-wiz: add a patch to use dev_err_probe() instead of dev_err() in
  the wiz_clock_init() function.
- phy-j721e-wiz: remove probe boolean for the wiz_clock_init(), rename the
  function to wiz_clock_probe(), extract hardware configuration part in a
  new function wiz_clock_init().
- phy-cadence-torrent: use dev_err_probe() and fix commit messages
- pcie-cadence-host: remove probe boolean for the cdns_pcie_host_setup()
  function and extract the link setup part in a new function
  cdns_pcie_host_link_setup().
- pcie-cadence-host: make cdns_pcie_host_init() global.
- pci-j721e: use the cdns_pcie_host_link_setup() cdns_pcie_host_init()
  functions in the resume_noirq() callback.
- Link to v2: https://lore.kernel.org/r/20240102-j7200-pcie-s2r-v2-0-8e4f7d228ec2@bootlin.com

Changes in v2:
- all: fix commits messages.
- all: use DEFINE_NOIRQ_DEV_PM_OPS and pm_sleep_ptr macros.
- all: remove useless #ifdef CONFIG_PM.
- pinctrl-single: drop dead code
- mux: add mux_chip_resume() function in mux core.
- mmio: resume sequence is now a call to mux_chip_resume().
- phy-cadence-torrent: fix typo in resume sequence (reset_control_assert()
  instead of reset_control_put()).
- phy-cadence-torrent: use PHY instead of phy.
- pci-j721e: do not shadow cdns_pcie_host_setup return code in resume
  sequence.
- pci-j721e: drop dead code.
- Link to v1: https://lore.kernel.org/r/20240102-j7200-pcie-s2r-v1-0-84e55da52400@bootlin.com

---
Thomas Richard (9):
      gpio: pca953x: move suspend()/resume() to suspend_noirq()/resume_noirq()
      i2c: omap: switch to NOIRQ_SYSTEM_SLEEP_PM_OPS() and RUNTIME_PM_OPS()
      i2c: omap: wakeup the controller during suspend() callback
      mux: add mux_chip_resume() function
      PCI: cadence: Extract link setup sequence from cdns_pcie_host_setup()
      PCI: cadence: Set cdns_pcie_host_init() global
      PCI: j721e: Use dev_err_probe() in the probe() function
      PCI: Add T_PERST_CLK_US macro
      PCI: j721e: Use T_PERST_CLK_US macro

Théo Lebrun (3):
      mux: mmio: add resume support
      PCI: j721e: Add reset GPIO to struct j721e_pcie
      PCI: j721e: Add suspend and resume support

 drivers/gpio/gpio-pca953x.c                        |   7 +-
 drivers/i2c/busses/i2c-omap.c                      |  36 ++++--
 drivers/mux/core.c                                 |  29 +++++
 drivers/mux/mmio.c                                 |  12 ++
 drivers/pci/controller/cadence/pci-j721e.c         | 121 ++++++++++++++++++---
 drivers/pci/controller/cadence/pcie-cadence-host.c |  44 +++++---
 drivers/pci/controller/cadence/pcie-cadence.h      |  12 ++
 drivers/pci/pci.h                                  |   3 +
 include/linux/mux/driver.h                         |   1 +
 9 files changed, 221 insertions(+), 44 deletions(-)
---
base-commit: cebffb4fba6177b15e60e28e1ac17fc4efb2f86f
change-id: 20240102-j7200-pcie-s2r-ecb1a979e357

Best regards,
-- 
Thomas Richard <thomas.richard@bootlin.com>

[PATCH v6 01/12] gpio: pca953x: move suspend()/resume() to suspend_noirq()/resume_noirq()

[Thomas Richard]

Some IOs can be needed during suspend_noirq()/resume_noirq().
So move suspend()/resume() to noirq.

Reviewed-by: Andi Shyti <andi.shyti@kernel.org>
Acked-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Thomas Richard <thomas.richard@bootlin.com>
---
 drivers/gpio/gpio-pca953x.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/gpio/gpio-pca953x.c b/drivers/gpio/gpio-pca953x.c
index 00ffa168e405..6e495fc67a93 100644
--- a/drivers/gpio/gpio-pca953x.c
+++ b/drivers/gpio/gpio-pca953x.c
@@ -1234,7 +1234,7 @@ static void pca953x_save_context(struct pca953x_chip *chip)
 	regcache_cache_only(chip->regmap, true);
 }
 
-static int pca953x_suspend(struct device *dev)
+static int pca953x_suspend_noirq(struct device *dev)
 {
 	struct pca953x_chip *chip = dev_get_drvdata(dev);
 
@@ -1248,7 +1248,7 @@ static int pca953x_suspend(struct device *dev)
 	return 0;
 }
 
-static int pca953x_resume(struct device *dev)
+static int pca953x_resume_noirq(struct device *dev)
 {
 	struct pca953x_chip *chip = dev_get_drvdata(dev);
 	int ret;
@@ -1268,7 +1268,8 @@ static int pca953x_resume(struct device *dev)
 	return ret;
 }
 
-static DEFINE_SIMPLE_DEV_PM_OPS(pca953x_pm_ops, pca953x_suspend, pca953x_resume);
+static DEFINE_NOIRQ_DEV_PM_OPS(pca953x_pm_ops,
+			       pca953x_suspend_noirq, pca953x_resume_noirq);
 
 /* convenience to stop overlong match-table lines */
 #define OF_653X(__nrgpio, __int) ((void *)(__nrgpio | PCAL653X_TYPE | __int))

-- 
2.39.2

[PATCH v6 02/12] i2c: omap: switch to NOIRQ_SYSTEM_SLEEP_PM_OPS() and RUNTIME_PM_OPS()

[Thomas Richard]

Replace SET_NOIRQ_SYSTEM_SLEEP_PM_OPS() and SET_RUNTIME_PM_OPS() by
NOIRQ_SYSTEM_SLEEP_PM_OPS() and RUNTIME_PM_OPS().
The usage of pm_ptr() and these more recent macros allows the compiler to
see and drop the dead code.
The unnecessary '__maybe_unused' annotations on PM functions can be
removed.

Signed-off-by: Thomas Richard <thomas.richard@bootlin.com>
---
 drivers/i2c/busses/i2c-omap.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 42165ef57946..258839845b12 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -1535,7 +1535,7 @@ static void omap_i2c_remove(struct platform_device *pdev)
 	pm_runtime_disable(&pdev->dev);
 }
 
-static int __maybe_unused omap_i2c_runtime_suspend(struct device *dev)
+static int omap_i2c_runtime_suspend(struct device *dev)
 {
 	struct omap_i2c_dev *omap = dev_get_drvdata(dev);
 
@@ -1561,7 +1561,7 @@ static int __maybe_unused omap_i2c_runtime_suspend(struct device *dev)
 	return 0;
 }
 
-static int __maybe_unused omap_i2c_runtime_resume(struct device *dev)
+static int omap_i2c_runtime_resume(struct device *dev)
 {
 	struct omap_i2c_dev *omap = dev_get_drvdata(dev);
 
@@ -1576,10 +1576,10 @@ static int __maybe_unused omap_i2c_runtime_resume(struct device *dev)
 }
 
 static const struct dev_pm_ops omap_i2c_pm_ops = {
-	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
-				      pm_runtime_force_resume)
-	SET_RUNTIME_PM_OPS(omap_i2c_runtime_suspend,
-			   omap_i2c_runtime_resume, NULL)
+	NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+				  pm_runtime_force_resume)
+	RUNTIME_PM_OPS(omap_i2c_runtime_suspend,
+		       omap_i2c_runtime_resume, NULL)
 };
 
 static struct platform_driver omap_i2c_driver = {
@@ -1587,7 +1587,7 @@ static struct platform_driver omap_i2c_driver = {
 	.remove_new	= omap_i2c_remove,
 	.driver		= {
 		.name	= "omap_i2c",
-		.pm	= &omap_i2c_pm_ops,
+		.pm	= pm_ptr(&omap_i2c_pm_ops),
 		.of_match_table = of_match_ptr(omap_i2c_of_match),
 	},
 };

-- 
2.39.2

[PATCH v6 03/12] i2c: omap: wakeup the controller during suspend() callback

[Thomas Richard]

A device may need the controller up during suspend_noirq() or
resume_noirq().
But if the controller is autosuspended, there is no way to wakeup it during
suspend_noirq() or resume_noirq() because runtime pm is disabled at this
time.

The suspend() callback wakes up the controller, so it is available until
its suspend_noirq() callback (pm_runtime_force_suspend()).
During the resume, it's restored by resume_noirq() callback
(pm_runtime_force_resume()). Then resume() callback enables autosuspend.

So the controller is up during a little time slot in suspend and resume
sequences even if it's not used.

Reviewed-by: Andi Shyti <andi.shyti@kernel.org>
Acked-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Thomas Richard <thomas.richard@bootlin.com>
---
 drivers/i2c/busses/i2c-omap.c | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 258839845b12..c767a6418962 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -1575,9 +1575,31 @@ static int omap_i2c_runtime_resume(struct device *dev)
 	return 0;
 }
 
+static int omap_i2c_suspend(struct device *dev)
+{
+	/*
+	 * If the controller is autosuspended, there is no way to wakeup it once
+	 * runtime pm is disabled (in suspend_late()).
+	 * But a device may need the controller up during suspend_noirq() or
+	 * resume_noirq().
+	 * Wakeup the controller while runtime pm is enabled, so it is available
+	 * until its suspend_noirq(), and from resume_noirq().
+	 */
+	return pm_runtime_resume_and_get(dev);
+}
+
+static int omap_i2c_resume(struct device *dev)
+{
+	pm_runtime_mark_last_busy(dev);
+	pm_runtime_put_autosuspend(dev);
+
+	return 0;
+}
+
 static const struct dev_pm_ops omap_i2c_pm_ops = {
 	NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
 				  pm_runtime_force_resume)
+	SYSTEM_SLEEP_PM_OPS(omap_i2c_suspend, omap_i2c_resume)
 	RUNTIME_PM_OPS(omap_i2c_runtime_suspend,
 		       omap_i2c_runtime_resume, NULL)
 };

-- 
2.39.2

[PATCH v6 04/12] mux: add mux_chip_resume() function

[Thomas Richard]

The mux_chip_resume() function restores a mux_chip using the cached state
of each mux.

Signed-off-by: Thomas Richard <thomas.richard@bootlin.com>
---
 drivers/mux/core.c         | 29 +++++++++++++++++++++++++++++
 include/linux/mux/driver.h |  1 +
 2 files changed, 30 insertions(+)

diff --git a/drivers/mux/core.c b/drivers/mux/core.c
index 775816112932..0742aa2a7c73 100644
--- a/drivers/mux/core.c
+++ b/drivers/mux/core.c
@@ -215,6 +215,35 @@ void mux_chip_free(struct mux_chip *mux_chip)
 }
 EXPORT_SYMBOL_GPL(mux_chip_free);
 
+/**
+ * mux_chip_resume() - restores the mux-chip state
+ * @mux_chip: The mux-chip to resume.
+ *
+ * Restores the mux-chip state.
+ *
+ * Return: Zero on success or a negative errno on error.
+ */
+int mux_chip_resume(struct mux_chip *mux_chip)
+{
+	int ret, i;
+
+	for (i = 0; i < mux_chip->controllers; ++i) {
+		struct mux_control *mux = &mux_chip->mux[i];
+
+		if (mux->cached_state == MUX_CACHE_UNKNOWN)
+			continue;
+
+		ret = mux_control_set(mux, mux->cached_state);
+		if (ret < 0) {
+			dev_err(&mux_chip->dev, "unable to restore state\n");
+			return ret;
+		}
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(mux_chip_resume);
+
 static void devm_mux_chip_release(struct device *dev, void *res)
 {
 	struct mux_chip *mux_chip = *(struct mux_chip **)res;
diff --git a/include/linux/mux/driver.h b/include/linux/mux/driver.h
index 18824064f8c0..2a7e5ec5d540 100644
--- a/include/linux/mux/driver.h
+++ b/include/linux/mux/driver.h
@@ -88,6 +88,7 @@ struct mux_chip *mux_chip_alloc(struct device *dev,
 int mux_chip_register(struct mux_chip *mux_chip);
 void mux_chip_unregister(struct mux_chip *mux_chip);
 void mux_chip_free(struct mux_chip *mux_chip);
+int mux_chip_resume(struct mux_chip *mux_chip);
 
 struct mux_chip *devm_mux_chip_alloc(struct device *dev,
 				     unsigned int controllers,

-- 
2.39.2

[PATCH v6 05/12] mux: mmio: add resume support

[Thomas Richard]

From: Théo Lebrun <theo.lebrun@bootlin.com>

No need to save something during the suspend stage, as the mux core has an
internal cache to store the state of muxes.

This cache is used by mux_chip_resume() to restore all muxes.

Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com>
Signed-off-by: Thomas Richard <thomas.richard@bootlin.com>
---
 drivers/mux/mmio.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/drivers/mux/mmio.c b/drivers/mux/mmio.c
index 30a952c34365..00405abe3ce3 100644
--- a/drivers/mux/mmio.c
+++ b/drivers/mux/mmio.c
@@ -130,13 +130,25 @@ static int mux_mmio_probe(struct platform_device *pdev)
 
 	mux_chip->ops = &mux_mmio_ops;
 
+	dev_set_drvdata(dev, mux_chip);
+
 	return devm_mux_chip_register(dev, mux_chip);
 }
 
+static int mux_mmio_resume_noirq(struct device *dev)
+{
+	struct mux_chip *mux_chip = dev_get_drvdata(dev);
+
+	return mux_chip_resume(mux_chip);
+}
+
+static DEFINE_NOIRQ_DEV_PM_OPS(mux_mmio_pm_ops, NULL, mux_mmio_resume_noirq);
+
 static struct platform_driver mux_mmio_driver = {
 	.driver = {
 		.name = "mmio-mux",
 		.of_match_table	= mux_mmio_dt_ids,
+		.pm = pm_sleep_ptr(&mux_mmio_pm_ops),
 	},
 	.probe = mux_mmio_probe,
 };

-- 
2.39.2

[PATCH v6 06/12] PCI: cadence: Extract link setup sequence from cdns_pcie_host_setup()

[Thomas Richard]

The function cdns_pcie_host_setup() mixes probe structure and link setup.

The link setup must be done during the resume sequence. So extract it from
cdns_pcie_host_setup() and create a dedicated function.

Reviewed-by: Siddharth Vadapalli <s-vadapalli@ti.com>
Signed-off-by: Thomas Richard <thomas.richard@bootlin.com>
---
 drivers/pci/controller/cadence/pcie-cadence-host.c | 39 ++++++++++++++--------
 drivers/pci/controller/cadence/pcie-cadence.h      |  6 ++++
 2 files changed, 32 insertions(+), 13 deletions(-)

diff --git a/drivers/pci/controller/cadence/pcie-cadence-host.c b/drivers/pci/controller/cadence/pcie-cadence-host.c
index 5b14f7ee3c79..93d9922730af 100644
--- a/drivers/pci/controller/cadence/pcie-cadence-host.c
+++ b/drivers/pci/controller/cadence/pcie-cadence-host.c
@@ -497,6 +497,30 @@ static int cdns_pcie_host_init(struct device *dev,
 	return cdns_pcie_host_init_address_translation(rc);
 }
 
+int cdns_pcie_host_link_setup(struct cdns_pcie_rc *rc)
+{
+	struct cdns_pcie *pcie = &rc->pcie;
+	struct device *dev = rc->pcie.dev;
+	int ret;
+
+	if (rc->quirk_detect_quiet_flag)
+		cdns_pcie_detect_quiet_min_delay_set(&rc->pcie);
+
+	cdns_pcie_host_enable_ptm_response(pcie);
+
+	ret = cdns_pcie_start_link(pcie);
+	if (ret) {
+		dev_err(dev, "Failed to start link\n");
+		return ret;
+	}
+
+	ret = cdns_pcie_host_start_link(rc);
+	if (ret)
+		dev_dbg(dev, "PCIe link never came up\n");
+
+	return 0;
+}
+
 int cdns_pcie_host_setup(struct cdns_pcie_rc *rc)
 {
 	struct device *dev = rc->pcie.dev;
@@ -533,20 +557,9 @@ int cdns_pcie_host_setup(struct cdns_pcie_rc *rc)
 		return PTR_ERR(rc->cfg_base);
 	rc->cfg_res = res;
 
-	if (rc->quirk_detect_quiet_flag)
-		cdns_pcie_detect_quiet_min_delay_set(&rc->pcie);
-
-	cdns_pcie_host_enable_ptm_response(pcie);
-
-	ret = cdns_pcie_start_link(pcie);
-	if (ret) {
-		dev_err(dev, "Failed to start link\n");
-		return ret;
-	}
-
-	ret = cdns_pcie_host_start_link(rc);
+	ret = cdns_pcie_host_link_setup(rc);
 	if (ret)
-		dev_dbg(dev, "PCIe link never came up\n");
+		return ret;
 
 	for (bar = RP_BAR0; bar <= RP_NO_BAR; bar++)
 		rc->avail_ib_bar[bar] = true;
diff --git a/drivers/pci/controller/cadence/pcie-cadence.h b/drivers/pci/controller/cadence/pcie-cadence.h
index 7a66a2f815dc..1d37d5f9f811 100644
--- a/drivers/pci/controller/cadence/pcie-cadence.h
+++ b/drivers/pci/controller/cadence/pcie-cadence.h
@@ -521,10 +521,16 @@ static inline bool cdns_pcie_link_up(struct cdns_pcie *pcie)
 }
 
 #ifdef CONFIG_PCIE_CADENCE_HOST
+int cdns_pcie_host_link_setup(struct cdns_pcie_rc *rc);
 int cdns_pcie_host_setup(struct cdns_pcie_rc *rc);
 void __iomem *cdns_pci_map_bus(struct pci_bus *bus, unsigned int devfn,
 			       int where);
 #else
+static inline int cdns_pcie_host_link_setup(struct cdns_pcie_rc *rc)
+{
+	return 0;
+}
+
 static inline int cdns_pcie_host_setup(struct cdns_pcie_rc *rc)
 {
 	return 0;

-- 
2.39.2

[PATCH v6 07/12] PCI: cadence: Set cdns_pcie_host_init() global

[Thomas Richard]

During the resume sequence of the host, cdns_pcie_host_init() needs to be
called, so set it global.

The dev function parameter is removed, as it isn't used.

Reviewed-by: Siddharth Vadapalli <s-vadapalli@ti.com>
Signed-off-by: Thomas Richard <thomas.richard@bootlin.com>
---
 drivers/pci/controller/cadence/pcie-cadence-host.c | 5 ++---
 drivers/pci/controller/cadence/pcie-cadence.h      | 6 ++++++
 2 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/drivers/pci/controller/cadence/pcie-cadence-host.c b/drivers/pci/controller/cadence/pcie-cadence-host.c
index 93d9922730af..8af95e9da7ce 100644
--- a/drivers/pci/controller/cadence/pcie-cadence-host.c
+++ b/drivers/pci/controller/cadence/pcie-cadence-host.c
@@ -485,8 +485,7 @@ static int cdns_pcie_host_init_address_translation(struct cdns_pcie_rc *rc)
 	return cdns_pcie_host_map_dma_ranges(rc);
 }
 
-static int cdns_pcie_host_init(struct device *dev,
-			       struct cdns_pcie_rc *rc)
+int cdns_pcie_host_init(struct cdns_pcie_rc *rc)
 {
 	int err;
 
@@ -564,7 +563,7 @@ int cdns_pcie_host_setup(struct cdns_pcie_rc *rc)
 	for (bar = RP_BAR0; bar <= RP_NO_BAR; bar++)
 		rc->avail_ib_bar[bar] = true;
 
-	ret = cdns_pcie_host_init(dev, rc);
+	ret = cdns_pcie_host_init(rc);
 	if (ret)
 		return ret;
 
diff --git a/drivers/pci/controller/cadence/pcie-cadence.h b/drivers/pci/controller/cadence/pcie-cadence.h
index 1d37d5f9f811..bb215aeebf20 100644
--- a/drivers/pci/controller/cadence/pcie-cadence.h
+++ b/drivers/pci/controller/cadence/pcie-cadence.h
@@ -522,6 +522,7 @@ static inline bool cdns_pcie_link_up(struct cdns_pcie *pcie)
 
 #ifdef CONFIG_PCIE_CADENCE_HOST
 int cdns_pcie_host_link_setup(struct cdns_pcie_rc *rc);
+int cdns_pcie_host_init(struct cdns_pcie_rc *rc);
 int cdns_pcie_host_setup(struct cdns_pcie_rc *rc);
 void __iomem *cdns_pci_map_bus(struct pci_bus *bus, unsigned int devfn,
 			       int where);
@@ -531,6 +532,11 @@ static inline int cdns_pcie_host_link_setup(struct cdns_pcie_rc *rc)
 	return 0;
 }
 
+static inline int cdns_pcie_host_init(struct cdns_pcie_rc *rc)
+{
+	return 0;
+}
+
 static inline int cdns_pcie_host_setup(struct cdns_pcie_rc *rc)
 {
 	return 0;

-- 
2.39.2

[PATCH v6 08/12] PCI: j721e: Use dev_err_probe() in the probe() function

[Thomas Richard]

Use dev_err_probe() instead of dev_err() in the probe() function to
simplify the code and standardize the error output.

Reviewed-by: Francesco Dolcini <francesco.dolcini@toradex.com>
Signed-off-by: Thomas Richard <thomas.richard@bootlin.com>
---
 drivers/pci/controller/cadence/pci-j721e.c | 19 ++++++++-----------
 1 file changed, 8 insertions(+), 11 deletions(-)

diff --git a/drivers/pci/controller/cadence/pci-j721e.c b/drivers/pci/controller/cadence/pci-j721e.c
index 85718246016b..98484f001562 100644
--- a/drivers/pci/controller/cadence/pci-j721e.c
+++ b/drivers/pci/controller/cadence/pci-j721e.c
@@ -482,20 +482,20 @@ static int j721e_pcie_probe(struct platform_device *pdev)
 	pm_runtime_enable(dev);
 	ret = pm_runtime_get_sync(dev);
 	if (ret < 0) {
-		dev_err(dev, "pm_runtime_get_sync failed\n");
+		dev_err_probe(dev, ret, "pm_runtime_get_sync failed\n");
 		goto err_get_sync;
 	}
 
 	ret = j721e_pcie_ctrl_init(pcie);
 	if (ret < 0) {
-		dev_err(dev, "pm_runtime_get_sync failed\n");
+		dev_err_probe(dev, ret, "pm_runtime_get_sync failed\n");
 		goto err_get_sync;
 	}
 
 	ret = devm_request_irq(dev, irq, j721e_pcie_link_irq_handler, 0,
 			       "j721e-pcie-link-down-irq", pcie);
 	if (ret < 0) {
-		dev_err(dev, "failed to request link state IRQ %d\n", irq);
+		dev_err_probe(dev, ret, "failed to request link state IRQ %d\n", irq);
 		goto err_get_sync;
 	}
 
@@ -505,28 +505,25 @@ static int j721e_pcie_probe(struct platform_device *pdev)
 	case PCI_MODE_RC:
 		gpiod = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
 		if (IS_ERR(gpiod)) {
-			ret = PTR_ERR(gpiod);
-			if (ret != -EPROBE_DEFER)
-				dev_err(dev, "Failed to get reset GPIO\n");
+			ret = dev_err_probe(dev, PTR_ERR(gpiod), "Failed to get reset GPIO\n");
 			goto err_get_sync;
 		}
 
 		ret = cdns_pcie_init_phy(dev, cdns_pcie);
 		if (ret) {
-			dev_err(dev, "Failed to init phy\n");
+			dev_err_probe(dev, ret, "Failed to init phy\n");
 			goto err_get_sync;
 		}
 
 		clk = devm_clk_get_optional(dev, "pcie_refclk");
 		if (IS_ERR(clk)) {
-			ret = PTR_ERR(clk);
-			dev_err(dev, "failed to get pcie_refclk\n");
+			ret = dev_err_probe(dev, PTR_ERR(clk), "failed to get pcie_refclk\n");
 			goto err_pcie_setup;
 		}
 
 		ret = clk_prepare_enable(clk);
 		if (ret) {
-			dev_err(dev, "failed to enable pcie_refclk\n");
+			dev_err_probe(dev, ret, "failed to enable pcie_refclk\n");
 			goto err_pcie_setup;
 		}
 		pcie->refclk = clk;
@@ -554,7 +551,7 @@ static int j721e_pcie_probe(struct platform_device *pdev)
 	case PCI_MODE_EP:
 		ret = cdns_pcie_init_phy(dev, cdns_pcie);
 		if (ret) {
-			dev_err(dev, "Failed to init phy\n");
+			dev_err_probe(dev, ret, "Failed to init phy\n");
 			goto err_get_sync;
 		}
 

-- 
2.39.2

[PATCH v6 09/12] PCI: j721e: Add reset GPIO to struct j721e_pcie

[Thomas Richard]

From: Théo Lebrun <theo.lebrun@bootlin.com>

Add reset GPIO to struct j721e_pcie, so it can be used at suspend and
resume stages.

Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com>
Signed-off-by: Thomas Richard <thomas.richard@bootlin.com>
---
 drivers/pci/controller/cadence/pci-j721e.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/pci/controller/cadence/pci-j721e.c b/drivers/pci/controller/cadence/pci-j721e.c
index 98484f001562..9af4fd64c1f9 100644
--- a/drivers/pci/controller/cadence/pci-j721e.c
+++ b/drivers/pci/controller/cadence/pci-j721e.c
@@ -52,6 +52,7 @@ struct j721e_pcie {
 	u32			mode;
 	u32			num_lanes;
 	u32			max_lanes;
+	struct gpio_desc	*reset_gpio;
 	void __iomem		*user_cfg_base;
 	void __iomem		*intd_cfg_base;
 	u32			linkdown_irq_regfield;
@@ -508,6 +509,7 @@ static int j721e_pcie_probe(struct platform_device *pdev)
 			ret = dev_err_probe(dev, PTR_ERR(gpiod), "Failed to get reset GPIO\n");
 			goto err_get_sync;
 		}
+		pcie->reset_gpio = gpiod;
 
 		ret = cdns_pcie_init_phy(dev, cdns_pcie);
 		if (ret) {

-- 
2.39.2

[PATCH v6 10/12] PCI: Add T_PERST_CLK_US macro

[Thomas Richard]

"Power Sequencing and Reset Signal Timings" table (section 2.9.2) in PCI
EXPRESS CARD ELECTROMECHANICAL SPECIFICATION, REV. 5.1 indicates PERST#
should be deasserted after minimum of 100us once REFCLK is stable (symbol
T_PERST-CLK).

Add a macro so that PCIe controller drivers can use it.

Signed-off-by: Thomas Richard <thomas.richard@bootlin.com>
---
 drivers/pci/pci.h | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index 17fed1846847..c47b1d3b5887 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -16,6 +16,9 @@
 /* Power stable to PERST# inactive from PCIe card Electromechanical Spec */
 #define PCIE_T_PVPERL_MS		100
 
+/* REFCLK stable before PERST# inactive from PCIe card Electromechanical Spec */
+#define PCIE_T_PERST_CLK_US		100
+
 /*
  * PCIe r6.0, sec 5.3.3.2.1 <PME Synchronization>
  * Recommends 1ms to 10ms timeout to check L2 ready.

-- 
2.39.2

[PATCH v6 11/12] PCI: j721e: Use T_PERST_CLK_US macro

[Thomas Richard]

Use the T_PERST_CLK_US macro, and the fsleep() function instead of
usleep_range().

Signed-off-by: Thomas Richard <thomas.richard@bootlin.com>
---
 drivers/pci/controller/cadence/pci-j721e.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/pci/controller/cadence/pci-j721e.c b/drivers/pci/controller/cadence/pci-j721e.c
index 9af4fd64c1f9..967a5bf38e26 100644
--- a/drivers/pci/controller/cadence/pci-j721e.c
+++ b/drivers/pci/controller/cadence/pci-j721e.c
@@ -539,7 +539,7 @@ static int j721e_pcie_probe(struct platform_device *pdev)
 		 * after 100 us.
 		 */
 		if (gpiod) {
-			usleep_range(100, 200);
+			fsleep(PCIE_T_PERST_CLK_US);
 			gpiod_set_value_cansleep(gpiod, 1);
 		}
 

-- 
2.39.2

[PATCH v6 12/12] PCI: j721e: Add suspend and resume support

[Thomas Richard]

From: Théo Lebrun <theo.lebrun@bootlin.com>

Add suspend and resume support. Only the rc mode is supported.

During the suspend stage PERST# is asserted, then deasserted during the
resume stage.

Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com>
Reviewed-by: Siddharth Vadapalli <s-vadapalli@ti.com>
Signed-off-by: Thomas Richard <thomas.richard@bootlin.com>
---
 drivers/pci/controller/cadence/pci-j721e.c | 98 ++++++++++++++++++++++++++++--
 1 file changed, 92 insertions(+), 6 deletions(-)

diff --git a/drivers/pci/controller/cadence/pci-j721e.c b/drivers/pci/controller/cadence/pci-j721e.c
index 967a5bf38e26..96316a79ab8a 100644
--- a/drivers/pci/controller/cadence/pci-j721e.c
+++ b/drivers/pci/controller/cadence/pci-j721e.c
@@ -7,6 +7,8 @@
  */
 
 #include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/container_of.h>
 #include <linux/delay.h>
 #include <linux/gpio/consumer.h>
 #include <linux/io.h>
@@ -22,6 +24,8 @@
 #include "../../pci.h"
 #include "pcie-cadence.h"
 
+#define cdns_pcie_to_rc(p) container_of(p, struct cdns_pcie_rc, pcie)
+
 #define ENABLE_REG_SYS_2	0x108
 #define STATUS_REG_SYS_2	0x508
 #define STATUS_CLR_REG_SYS_2	0x708
@@ -531,12 +535,12 @@ static int j721e_pcie_probe(struct platform_device *pdev)
 		pcie->refclk = clk;
 
 		/*
-		 * "Power Sequencing and Reset Signal Timings" table in
-		 * PCI EXPRESS CARD ELECTROMECHANICAL SPECIFICATION, REV. 3.0
-		 * indicates PERST# should be deasserted after minimum of 100us
-		 * once REFCLK is stable. The REFCLK to the connector in RC
-		 * mode is selected while enabling the PHY. So deassert PERST#
-		 * after 100 us.
+		 * "Power Sequencing and Reset Signal Timings" table (section
+		 * 2.9.2) in PCI EXPRESS CARD ELECTROMECHANICAL SPECIFICATION,
+		 * REV. 5.1 indicates PERST# should be deasserted after minimum
+		 * of 100us once REFCLK is stable (symbol T_PERST-CLK).
+		 * The REFCLK to the connector in RC mode is selected while
+		 * enabling the PHY. So deassert PERST# after 100 us.
 		 */
 		if (gpiod) {
 			fsleep(PCIE_T_PERST_CLK_US);
@@ -588,6 +592,87 @@ static void j721e_pcie_remove(struct platform_device *pdev)
 	pm_runtime_disable(dev);
 }
 
+static int j721e_pcie_suspend_noirq(struct device *dev)
+{
+	struct j721e_pcie *pcie = dev_get_drvdata(dev);
+
+	if (pcie->mode == PCI_MODE_RC) {
+		gpiod_set_value_cansleep(pcie->reset_gpio, 0);
+		clk_disable_unprepare(pcie->refclk);
+	}
+
+	cdns_pcie_disable_phy(pcie->cdns_pcie);
+
+	return 0;
+}
+
+static int j721e_pcie_resume_noirq(struct device *dev)
+{
+	struct j721e_pcie *pcie = dev_get_drvdata(dev);
+	struct cdns_pcie *cdns_pcie = pcie->cdns_pcie;
+	int ret;
+
+	ret = j721e_pcie_ctrl_init(pcie);
+	if (ret < 0)
+		return ret;
+
+	j721e_pcie_config_link_irq(pcie);
+
+	/*
+	 * This is not called explicitly in the probe, it is called by
+	 * cdns_pcie_init_phy().
+	 */
+	ret = cdns_pcie_enable_phy(pcie->cdns_pcie);
+	if (ret < 0)
+		return ret;
+
+	if (pcie->mode == PCI_MODE_RC) {
+		struct cdns_pcie_rc *rc = cdns_pcie_to_rc(cdns_pcie);
+
+		ret = clk_prepare_enable(pcie->refclk);
+		if (ret < 0)
+			return ret;
+
+		/*
+		 * "Power Sequencing and Reset Signal Timings" table (section
+		 * 2.9.2) in PCI EXPRESS CARD ELECTROMECHANICAL SPECIFICATION,
+		 * REV. 5.1 indicates PERST# should be deasserted after minimum
+		 * of 100us once REFCLK is stable (symbol T_PERST-CLK).
+		 * The REFCLK to the connector in RC mode is selected while
+		 * enabling the PHY. So deassert PERST# after 100 us.
+		 */
+		if (pcie->reset_gpio) {
+			fsleep(PCIE_T_PERST_CLK_US);
+			gpiod_set_value_cansleep(pcie->reset_gpio, 1);
+		}
+
+		ret = cdns_pcie_host_link_setup(rc);
+		if (ret < 0) {
+			clk_disable_unprepare(pcie->refclk);
+			return ret;
+		}
+
+		/*
+		 * Reset internal status of BARs to force reinitialization in
+		 * cdns_pcie_host_init().
+		 */
+		for (enum cdns_pcie_rp_bar bar = RP_BAR0; bar <= RP_NO_BAR; bar++)
+			rc->avail_ib_bar[bar] = true;
+
+		ret = cdns_pcie_host_init(rc);
+		if (ret) {
+			clk_disable_unprepare(pcie->refclk);
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
+static DEFINE_NOIRQ_DEV_PM_OPS(j721e_pcie_pm_ops,
+			       j721e_pcie_suspend_noirq,
+			       j721e_pcie_resume_noirq);
+
 static struct platform_driver j721e_pcie_driver = {
 	.probe  = j721e_pcie_probe,
 	.remove_new = j721e_pcie_remove,
@@ -595,6 +680,7 @@ static struct platform_driver j721e_pcie_driver = {
 		.name	= "j721e-pcie",
 		.of_match_table = of_j721e_pcie_match,
 		.suppress_bind_attrs = true,
+		.pm	= pm_sleep_ptr(&j721e_pcie_pm_ops),
 	},
 };
 builtin_platform_driver(j721e_pcie_driver);

-- 
2.39.2

Re: [PATCH v6 00/12] Add suspend to ram support for PCIe on J7200

[Thomas Richard]

On 5/15/24 12:01, Thomas Richard wrote:
> This adds suspend to ram support for the PCIe (RC mode) on J7200 platform.
> 

Hello,

Gentle ping.
No merge conflict with 6.10-rc1.
I know the patch for the gpio-pca953x driver causes a regression for one
other platform.
But most of the patches could be applied.

Best Regards,

Thomas

-- 
Thomas Richard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

Re: [PATCH v6 00/12] Add suspend to ram support for PCIe on J7200

[Bartosz Golaszewski]

On Fri, May 31, 2024 at 6:55 PM Thomas Richard
<thomas.richard@bootlin.com> wrote:
>
> On 5/15/24 12:01, Thomas Richard wrote:
> > This adds suspend to ram support for the PCIe (RC mode) on J7200 platform.
> >
>
> Hello,
>
> Gentle ping.
> No merge conflict with 6.10-rc1.
> I know the patch for the gpio-pca953x driver causes a regression for one
> other platform.
> But most of the patches could be applied.
>
> Best Regards,
>
> Thomas
>

If the patches targeting different subsystems don't depend on each
other then you'd have more chance of getting them picked up by
splitting the series up and sending individual bits and pieces to
appropriate maintainers separately.

Bart