Commit bcdb6fd4 authored by Pali Rohár's avatar Pali Rohár Committed by Bjorn Helgaas
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PCI: aardvark: Fix reporting Slot capabilities on emulated bridge 

Slot capabilities are currently not reported because emulated bridge does
not report the PCI_EXP_FLAGS_SLOT flag.

Set PCI_EXP_FLAGS_SLOT to let the kernel know that PCI_EXP_SLT* registers
are supported.

Move setting of PCI_EXP_SLTCTL register from "dynamic" pcie_conf_read
function to static buffer as it is only statically filled the
PCI_EXP_SLTSTA_PDS flag and dynamic read callback is not needed for this
register.

Set Presence State Bit to 1 since there is no support for unplugging the
card and there is currently no platform able to detect presence of a card -
in such a case the bit needs to be set to 1.

Finally correctly set Physical Slot Number to 1 since there is only one
port and zero value is reserved for ports within the same silicon as Root
Port which is not our case for Aardvark HW.

Link: https://lore.kernel.org/r/20220524132827.8837-3-kabel@kernel.org


Signed-off-by: default avatarPali Rohár <pali@kernel.org>
Signed-off-by: default avatarMarek Behún <kabel@kernel.org>
Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
parent 1326b496

drivers/pci/controller/pci-aardvark.c

+24 −9
Original line number Diff line number Diff line
@@ -8,6 +8,7 @@ 
 * Author: Hezi Shahmoon <hezi.shahmoon@marvell.com>

 */



#include <linux/bitfield.h>

#include <linux/delay.h>

#include <linux/gpio/consumer.h>

#include <linux/interrupt.h>
@@ -858,14 +859,11 @@ advk_pci_bridge_emul_pcie_conf_read(struct pci_bridge_emul *bridge, 




	switch (reg) {

	case PCI_EXP_SLTCTL:

		*value = PCI_EXP_SLTSTA_PDS << 16;

		return PCI_BRIDGE_EMUL_HANDLED;



	/*

	 * PCI_EXP_RTCTL and PCI_EXP_RTSTA are also supported, but do not need

	 * to be handled here, because their values are stored in emulated

	 * config space buffer, and we read them from there when needed.

	 * PCI_EXP_SLTCAP, PCI_EXP_SLTCTL, PCI_EXP_RTCTL and PCI_EXP_RTSTA are

	 * also supported, but do not need to be handled here, because their

	 * values are stored in emulated config space buffer, and we read them

	 * from there when needed.

	 */



	case PCI_EXP_LNKCAP: {
@@ -1056,8 +1054,25 @@ static int advk_sw_pci_bridge_init(struct advk_pcie *pcie) 
	/* Support interrupt A for MSI feature */

	bridge->conf.intpin = PCI_INTERRUPT_INTA;



	/* Aardvark HW provides PCIe Capability structure in version 2 */

	bridge->pcie_conf.cap = cpu_to_le16(2);

	/*

	 * Aardvark HW provides PCIe Capability structure in version 2 and

	 * indicate slot support, which is emulated.

	 */

	bridge->pcie_conf.cap = cpu_to_le16(2 | PCI_EXP_FLAGS_SLOT);



	/*

	 * Set Presence Detect State bit permanently since there is no support

	 * for unplugging the card nor detecting whether it is plugged. (If a

	 * platform exists in the future that supports it, via a GPIO for

	 * example, it should be implemented via this bit.)

	 *

	 * Set physical slot number to 1 since there is only one port and zero

	 * value is reserved for ports within the same silicon as Root Port

	 * which is not our case.

	 */

	bridge->pcie_conf.slotcap = cpu_to_le32(FIELD_PREP(PCI_EXP_SLTCAP_PSN,

							   1));

	bridge->pcie_conf.slotsta = cpu_to_le16(PCI_EXP_SLTSTA_PDS);



	/* Indicates supports for Completion Retry Status */

	bridge->pcie_conf.rootcap = cpu_to_le16(PCI_EXP_RTCAP_CRSVIS);