Commit 420be2f7 authored by Bjorn Helgaas's avatar Bjorn Helgaas
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Revert "PCI: brcmstb: Add mechanism to turn on subdev regulators" 

This reverts commit 67211aad.

This is part of a revert of the following commits:

  11ed8b86 ("PCI: brcmstb: Do not turn off WOL regulators on suspend")
  93e41f3f ("PCI: brcmstb: Add control of subdevice voltage regulators")
  67211aad ("PCI: brcmstb: Add mechanism to turn on subdev regulators")
  830aa6f2 ("PCI: brcmstb: Split brcm_pcie_setup() into two funcs")

Cyril reported that 830aa6f2 ("PCI: brcmstb: Split brcm_pcie_setup()
into two funcs"), which appeared in v5.17-rc1, broke booting on the
Raspberry Pi Compute Module 4.  Apparently 830aa6f2 panics with an
Asynchronous SError Interrupt, and after further commits here is a black
screen on HDMI and no output on the serial console.

This does not seem to affect the Raspberry Pi 4 B.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=215925
Link: https://lore.kernel.org/r/20220511201856.808690-4-helgaas@kernel.org


Reported-by: default avatarCyril Brulebois <kibi@debian.org>
Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
parent 21294260

drivers/pci/controller/pcie-brcmstb.c

+0 −76
Original line number Diff line number Diff line
@@ -24,7 +24,6 @@ 
#include <linux/pci.h>

#include <linux/pci-ecam.h>

#include <linux/printk.h>

#include <linux/regulator/consumer.h>

#include <linux/reset.h>

#include <linux/sizes.h>

#include <linux/slab.h>
@@ -284,14 +283,6 @@ static const struct pcie_cfg_data bcm2711_cfg = { 
	.bridge_sw_init_set = brcm_pcie_bridge_sw_init_set_generic,

};



struct subdev_regulators {

	unsigned int num_supplies;

	struct regulator_bulk_data supplies[];

};



static int pci_subdev_regulators_add_bus(struct pci_bus *bus);

static void pci_subdev_regulators_remove_bus(struct pci_bus *bus);



struct brcm_msi {

	struct device		*dev;

	void __iomem		*base;
@@ -445,71 +436,6 @@ static int brcm_pcie_set_ssc(struct brcm_pcie *pcie) 
	return ssc && pll ? 0 : -EIO;

}



static void *alloc_subdev_regulators(struct device *dev)

{

	static const char * const supplies[] = {

		"vpcie3v3",

		"vpcie3v3aux",

		"vpcie12v",

	};

	const size_t size = sizeof(struct subdev_regulators)

		+ sizeof(struct regulator_bulk_data) * ARRAY_SIZE(supplies);

	struct subdev_regulators *sr;

	int i;



	sr = devm_kzalloc(dev, size, GFP_KERNEL);

	if (sr) {

		sr->num_supplies = ARRAY_SIZE(supplies);

		for (i = 0; i < ARRAY_SIZE(supplies); i++)

			sr->supplies[i].supply = supplies[i];

	}



	return sr;

}



static int pci_subdev_regulators_add_bus(struct pci_bus *bus)

{

	struct device *dev = &bus->dev;

	struct subdev_regulators *sr;

	int ret;



	if (!dev->of_node || !bus->parent || !pci_is_root_bus(bus->parent))

		return 0;



	if (dev->driver_data)

		dev_err(dev, "dev.driver_data unexpectedly non-NULL\n");



	sr = alloc_subdev_regulators(dev);

	if (!sr)

		return -ENOMEM;



	dev->driver_data = sr;

	ret = regulator_bulk_get(dev, sr->num_supplies, sr->supplies);

	if (ret)

		return ret;



	ret = regulator_bulk_enable(sr->num_supplies, sr->supplies);

	if (ret) {

		dev_err(dev, "failed to enable regulators for downstream device\n");

		return ret;

	}



	return 0;

}



static void pci_subdev_regulators_remove_bus(struct pci_bus *bus)

{

	struct device *dev = &bus->dev;

	struct subdev_regulators *sr = dev->driver_data;



	if (!sr || !bus->parent || !pci_is_root_bus(bus->parent))

		return;



	if (regulator_bulk_disable(sr->num_supplies, sr->supplies))

		dev_err(dev, "failed to disable regulators for downstream device\n");

	dev->driver_data = NULL;

}



/* Limits operation to a specific generation (1, 2, or 3) */

static void brcm_pcie_set_gen(struct brcm_pcie *pcie, int gen)

{
@@ -853,8 +779,6 @@ static struct pci_ops brcm_pcie_ops = { 
	.map_bus = brcm_pcie_map_conf,

	.read = pci_generic_config_read,

	.write = pci_generic_config_write,

	.add_bus = pci_subdev_regulators_add_bus,

	.remove_bus = pci_subdev_regulators_remove_bus,

};



static struct pci_ops brcm_pcie_ops32 = {