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23 October 2021, 00:29:24 UTC
Revision 275e88b06a277ccf89d9c471a777e9b4f8c552b0 authored by Rob Herring on 18 December 2020, 14:39:05 UTC, committed by Bjorn Helgaas on 26 December 2020, 03:58:36 UTC 
PCI: tegra: Fix host link initialization
 
Commit b9ac0f9dc8ea ("PCI: dwc: Move dw_pcie_setup_rc() to DWC common
code") broke enumeration of downstream devices on Tegra:

In non-working case (next-20201211):

  0001:00:00.0 PCI bridge: NVIDIA Corporation Device 1ad2 (rev a1)
  0001:01:00.0 SATA controller: Marvell Technology Group Ltd. Device 9171 (rev 13)
  0005:00:00.0 PCI bridge: NVIDIA Corporation Device 1ad0 (rev a1)

In working case (v5.10-rc7):

  0001:00:00.0 PCI bridge: Molex Incorporated Device 1ad2 (rev a1)
  0001:01:00.0 SATA controller: Marvell Technology Group Ltd. Device 9171 (rev 13)
  0005:00:00.0 PCI bridge: Molex Incorporated Device 1ad0 (rev a1)
  0005:01:00.0 PCI bridge: PLX Technology, Inc. Device 3380 (rev ab)
  0005:02:02.0 PCI bridge: PLX Technology, Inc. Device 3380 (rev ab)
  0005:03:00.0 USB controller: PLX Technology, Inc. Device 3380 (rev ab)

The problem seems to be dw_pcie_setup_rc() is now called twice before and
after the link up handling. The fix is to move Tegra's link up handling to
.start_link() function like other DWC drivers. Tegra is a bit more
complicated than others as it re-inits the whole DWC controller to retry
the link. With this, the initialization ordering is restored to match the
prior sequence.

Fixes: b9ac0f9dc8ea ("PCI: dwc: Move dw_pcie_setup_rc() to DWC common code")
Link: https://lore.kernel.org/r/20201218143905.1614098-1-robh@kernel.org
Reported-by: Mian Yousaf Kaukab <ykaukab@suse.de>
Tested-by: Mian Yousaf Kaukab <ykaukab@suse.de>
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Jonathan Hunter <jonathanh@nvidia.com>
Cc: Vidya Sagar <vidyas@nvidia.com>
1 parent 255b2d5
Raw File
Tip revision: 275e88b06a277ccf89d9c471a777e9b4f8c552b0 authored by Rob Herring on 18 December 2020, 14:39:05 UTC
PCI: tegra: Fix host link initialization
Tip revision: 275e88b
sbshc.h 
/* SPDX-License-Identifier: GPL-2.0 */
struct acpi_smb_hc;
enum acpi_smb_protocol {
	SMBUS_WRITE_QUICK = 2,
	SMBUS_READ_QUICK = 3,
	SMBUS_SEND_BYTE = 4,
	SMBUS_RECEIVE_BYTE = 5,
	SMBUS_WRITE_BYTE = 6,
	SMBUS_READ_BYTE = 7,
	SMBUS_WRITE_WORD  = 8,
	SMBUS_READ_WORD  = 9,
	SMBUS_WRITE_BLOCK = 0xa,
	SMBUS_READ_BLOCK = 0xb,
	SMBUS_PROCESS_CALL = 0xc,
	SMBUS_BLOCK_PROCESS_CALL = 0xd,
};

enum acpi_sbs_device_addr {
	ACPI_SBS_CHARGER = 0x9,
	ACPI_SBS_MANAGER = 0xa,
	ACPI_SBS_BATTERY = 0xb,
};

typedef void (*smbus_alarm_callback)(void *context);

extern int acpi_smbus_read(struct acpi_smb_hc *hc, u8 protocol, u8 address,
	       u8 command, u8 * data);
extern int acpi_smbus_write(struct acpi_smb_hc *hc, u8 protocol, u8 slave_address,
		u8 command, u8 * data, u8 length);
extern int acpi_smbus_register_callback(struct acpi_smb_hc *hc,
			         smbus_alarm_callback callback, void *context);
extern int acpi_smbus_unregister_callback(struct acpi_smb_hc *hc);
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