[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