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linux/drivers/pci/pci-bridge-emul.h

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PCI: Introduce PCI bridge emulated config space common logic Some PCI host controllers do not expose a configuration space for the root port PCI bridge. Due to this, the Marvell Armada 370/38x/XP PCI controller driver (pci-mvebu) emulates a root port PCI bridge configuration space, and uses that to (among other things) dynamically create the memory windows that correspond to the PCI MEM and I/O regions. Since we now need to add a very similar logic for the Marvell Armada 37xx PCI controller driver (pci-aardvark), instead of duplicating the code, we create in this commit a common logic called pci-bridge-emul. The idea of this logic is to emulate a root port PCI bridge configuration space by providing configuration space read/write operations, and faking behind the scenes the configuration space of a PCI bridge. A PCI host controller driver simply has to call pci_bridge_emul_conf_read() and pci_bridge_emul_conf_write() to read/write the configuration space of the bridge. By default, the PCI bridge configuration space is simply emulated by a chunk of memory, but the PCI host controller can override the behavior of the read and write operations on a per-register basis to do additional actions if needed. We take care of complying with the behavior of the PCI configuration space registers in terms of bits that are read-write, read-only, reserved and write-1-to-clear. Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-10-18 18:37:16 +03:00
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __PCI_BRIDGE_EMUL_H__
#define __PCI_BRIDGE_EMUL_H__
#include <linux/kernel.h>
/* PCI configuration space of a PCI-to-PCI bridge. */
struct pci_bridge_emul_conf {
PCI: pci-bridge-emul: Fix big-endian support Perform conversion to little-endian before every write to configuration space and convert it back to CPU endianness on reads. Additionally, initialise every multiple byte field of config space with the cpu_to_le* macro, which is required since the structure describing config space of emulated bridge assumes little-endian convention. Signed-off-by: Grzegorz Jaszczyk <jaz@semihalf.com> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
2019-07-16 15:13:46 +03:00
__le16 vendor;
__le16 device;
__le16 command;
__le16 status;
__le32 class_revision;
PCI: Introduce PCI bridge emulated config space common logic Some PCI host controllers do not expose a configuration space for the root port PCI bridge. Due to this, the Marvell Armada 370/38x/XP PCI controller driver (pci-mvebu) emulates a root port PCI bridge configuration space, and uses that to (among other things) dynamically create the memory windows that correspond to the PCI MEM and I/O regions. Since we now need to add a very similar logic for the Marvell Armada 37xx PCI controller driver (pci-aardvark), instead of duplicating the code, we create in this commit a common logic called pci-bridge-emul. The idea of this logic is to emulate a root port PCI bridge configuration space by providing configuration space read/write operations, and faking behind the scenes the configuration space of a PCI bridge. A PCI host controller driver simply has to call pci_bridge_emul_conf_read() and pci_bridge_emul_conf_write() to read/write the configuration space of the bridge. By default, the PCI bridge configuration space is simply emulated by a chunk of memory, but the PCI host controller can override the behavior of the read and write operations on a per-register basis to do additional actions if needed. We take care of complying with the behavior of the PCI configuration space registers in terms of bits that are read-write, read-only, reserved and write-1-to-clear. Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-10-18 18:37:16 +03:00
u8 cache_line_size;
u8 latency_timer;
u8 header_type;
u8 bist;
PCI: pci-bridge-emul: Fix big-endian support Perform conversion to little-endian before every write to configuration space and convert it back to CPU endianness on reads. Additionally, initialise every multiple byte field of config space with the cpu_to_le* macro, which is required since the structure describing config space of emulated bridge assumes little-endian convention. Signed-off-by: Grzegorz Jaszczyk <jaz@semihalf.com> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
2019-07-16 15:13:46 +03:00
__le32 bar[2];
PCI: Introduce PCI bridge emulated config space common logic Some PCI host controllers do not expose a configuration space for the root port PCI bridge. Due to this, the Marvell Armada 370/38x/XP PCI controller driver (pci-mvebu) emulates a root port PCI bridge configuration space, and uses that to (among other things) dynamically create the memory windows that correspond to the PCI MEM and I/O regions. Since we now need to add a very similar logic for the Marvell Armada 37xx PCI controller driver (pci-aardvark), instead of duplicating the code, we create in this commit a common logic called pci-bridge-emul. The idea of this logic is to emulate a root port PCI bridge configuration space by providing configuration space read/write operations, and faking behind the scenes the configuration space of a PCI bridge. A PCI host controller driver simply has to call pci_bridge_emul_conf_read() and pci_bridge_emul_conf_write() to read/write the configuration space of the bridge. By default, the PCI bridge configuration space is simply emulated by a chunk of memory, but the PCI host controller can override the behavior of the read and write operations on a per-register basis to do additional actions if needed. We take care of complying with the behavior of the PCI configuration space registers in terms of bits that are read-write, read-only, reserved and write-1-to-clear. Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-10-18 18:37:16 +03:00
u8 primary_bus;
u8 secondary_bus;
u8 subordinate_bus;
u8 secondary_latency_timer;
u8 iobase;
u8 iolimit;
PCI: pci-bridge-emul: Fix big-endian support Perform conversion to little-endian before every write to configuration space and convert it back to CPU endianness on reads. Additionally, initialise every multiple byte field of config space with the cpu_to_le* macro, which is required since the structure describing config space of emulated bridge assumes little-endian convention. Signed-off-by: Grzegorz Jaszczyk <jaz@semihalf.com> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
2019-07-16 15:13:46 +03:00
__le16 secondary_status;
__le16 membase;
__le16 memlimit;
__le16 pref_mem_base;
__le16 pref_mem_limit;
__le32 prefbaseupper;
__le32 preflimitupper;
__le16 iobaseupper;
__le16 iolimitupper;
PCI: Introduce PCI bridge emulated config space common logic Some PCI host controllers do not expose a configuration space for the root port PCI bridge. Due to this, the Marvell Armada 370/38x/XP PCI controller driver (pci-mvebu) emulates a root port PCI bridge configuration space, and uses that to (among other things) dynamically create the memory windows that correspond to the PCI MEM and I/O regions. Since we now need to add a very similar logic for the Marvell Armada 37xx PCI controller driver (pci-aardvark), instead of duplicating the code, we create in this commit a common logic called pci-bridge-emul. The idea of this logic is to emulate a root port PCI bridge configuration space by providing configuration space read/write operations, and faking behind the scenes the configuration space of a PCI bridge. A PCI host controller driver simply has to call pci_bridge_emul_conf_read() and pci_bridge_emul_conf_write() to read/write the configuration space of the bridge. By default, the PCI bridge configuration space is simply emulated by a chunk of memory, but the PCI host controller can override the behavior of the read and write operations on a per-register basis to do additional actions if needed. We take care of complying with the behavior of the PCI configuration space registers in terms of bits that are read-write, read-only, reserved and write-1-to-clear. Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-10-18 18:37:16 +03:00
u8 capabilities_pointer;
u8 reserve[3];
PCI: pci-bridge-emul: Fix big-endian support Perform conversion to little-endian before every write to configuration space and convert it back to CPU endianness on reads. Additionally, initialise every multiple byte field of config space with the cpu_to_le* macro, which is required since the structure describing config space of emulated bridge assumes little-endian convention. Signed-off-by: Grzegorz Jaszczyk <jaz@semihalf.com> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
2019-07-16 15:13:46 +03:00
__le32 romaddr;
PCI: Introduce PCI bridge emulated config space common logic Some PCI host controllers do not expose a configuration space for the root port PCI bridge. Due to this, the Marvell Armada 370/38x/XP PCI controller driver (pci-mvebu) emulates a root port PCI bridge configuration space, and uses that to (among other things) dynamically create the memory windows that correspond to the PCI MEM and I/O regions. Since we now need to add a very similar logic for the Marvell Armada 37xx PCI controller driver (pci-aardvark), instead of duplicating the code, we create in this commit a common logic called pci-bridge-emul. The idea of this logic is to emulate a root port PCI bridge configuration space by providing configuration space read/write operations, and faking behind the scenes the configuration space of a PCI bridge. A PCI host controller driver simply has to call pci_bridge_emul_conf_read() and pci_bridge_emul_conf_write() to read/write the configuration space of the bridge. By default, the PCI bridge configuration space is simply emulated by a chunk of memory, but the PCI host controller can override the behavior of the read and write operations on a per-register basis to do additional actions if needed. We take care of complying with the behavior of the PCI configuration space registers in terms of bits that are read-write, read-only, reserved and write-1-to-clear. Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-10-18 18:37:16 +03:00
u8 intline;
u8 intpin;
PCI: pci-bridge-emul: Fix big-endian support Perform conversion to little-endian before every write to configuration space and convert it back to CPU endianness on reads. Additionally, initialise every multiple byte field of config space with the cpu_to_le* macro, which is required since the structure describing config space of emulated bridge assumes little-endian convention. Signed-off-by: Grzegorz Jaszczyk <jaz@semihalf.com> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
2019-07-16 15:13:46 +03:00
__le16 bridgectrl;
PCI: Introduce PCI bridge emulated config space common logic Some PCI host controllers do not expose a configuration space for the root port PCI bridge. Due to this, the Marvell Armada 370/38x/XP PCI controller driver (pci-mvebu) emulates a root port PCI bridge configuration space, and uses that to (among other things) dynamically create the memory windows that correspond to the PCI MEM and I/O regions. Since we now need to add a very similar logic for the Marvell Armada 37xx PCI controller driver (pci-aardvark), instead of duplicating the code, we create in this commit a common logic called pci-bridge-emul. The idea of this logic is to emulate a root port PCI bridge configuration space by providing configuration space read/write operations, and faking behind the scenes the configuration space of a PCI bridge. A PCI host controller driver simply has to call pci_bridge_emul_conf_read() and pci_bridge_emul_conf_write() to read/write the configuration space of the bridge. By default, the PCI bridge configuration space is simply emulated by a chunk of memory, but the PCI host controller can override the behavior of the read and write operations on a per-register basis to do additional actions if needed. We take care of complying with the behavior of the PCI configuration space registers in terms of bits that are read-write, read-only, reserved and write-1-to-clear. Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-10-18 18:37:16 +03:00
};
/* PCI configuration space of the PCIe capabilities */
struct pci_bridge_emul_pcie_conf {
u8 cap_id;
u8 next;
PCI: pci-bridge-emul: Fix big-endian support Perform conversion to little-endian before every write to configuration space and convert it back to CPU endianness on reads. Additionally, initialise every multiple byte field of config space with the cpu_to_le* macro, which is required since the structure describing config space of emulated bridge assumes little-endian convention. Signed-off-by: Grzegorz Jaszczyk <jaz@semihalf.com> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
2019-07-16 15:13:46 +03:00
__le16 cap;
__le32 devcap;
__le16 devctl;
__le16 devsta;
__le32 lnkcap;
__le16 lnkctl;
__le16 lnksta;
__le32 slotcap;
__le16 slotctl;
__le16 slotsta;
__le16 rootctl;
__le16 rsvd;
__le32 rootsta;
__le32 devcap2;
__le16 devctl2;
__le16 devsta2;
__le32 lnkcap2;
__le16 lnkctl2;
__le16 lnksta2;
__le32 slotcap2;
__le16 slotctl2;
__le16 slotsta2;
PCI: Introduce PCI bridge emulated config space common logic Some PCI host controllers do not expose a configuration space for the root port PCI bridge. Due to this, the Marvell Armada 370/38x/XP PCI controller driver (pci-mvebu) emulates a root port PCI bridge configuration space, and uses that to (among other things) dynamically create the memory windows that correspond to the PCI MEM and I/O regions. Since we now need to add a very similar logic for the Marvell Armada 37xx PCI controller driver (pci-aardvark), instead of duplicating the code, we create in this commit a common logic called pci-bridge-emul. The idea of this logic is to emulate a root port PCI bridge configuration space by providing configuration space read/write operations, and faking behind the scenes the configuration space of a PCI bridge. A PCI host controller driver simply has to call pci_bridge_emul_conf_read() and pci_bridge_emul_conf_write() to read/write the configuration space of the bridge. By default, the PCI bridge configuration space is simply emulated by a chunk of memory, but the PCI host controller can override the behavior of the read and write operations on a per-register basis to do additional actions if needed. We take care of complying with the behavior of the PCI configuration space registers in terms of bits that are read-write, read-only, reserved and write-1-to-clear. Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-10-18 18:37:16 +03:00
};
struct pci_bridge_emul;
typedef enum { PCI_BRIDGE_EMUL_HANDLED,
PCI_BRIDGE_EMUL_NOT_HANDLED } pci_bridge_emul_read_status_t;
struct pci_bridge_emul_ops {
/*
* Called when reading from the regular PCI bridge
* configuration space. Return PCI_BRIDGE_EMUL_HANDLED when the
* operation has handled the read operation and filled in the
* *value, or PCI_BRIDGE_EMUL_NOT_HANDLED when the read should
* be emulated by the common code by reading from the
* in-memory copy of the configuration space.
*/
pci_bridge_emul_read_status_t (*read_base)(struct pci_bridge_emul *bridge,
int reg, u32 *value);
/*
* Same as ->read_base(), except it is for reading from the
* PCIe capability configuration space.
*/
pci_bridge_emul_read_status_t (*read_pcie)(struct pci_bridge_emul *bridge,
int reg, u32 *value);
/*
* Called when writing to the regular PCI bridge configuration
* space. old is the current value, new is the new value being
* written, and mask indicates which parts of the value are
* being changed.
*/
void (*write_base)(struct pci_bridge_emul *bridge, int reg,
u32 old, u32 new, u32 mask);
/*
* Same as ->write_base(), except it is for writing from the
* PCIe capability configuration space.
*/
void (*write_pcie)(struct pci_bridge_emul *bridge, int reg,
u32 old, u32 new, u32 mask);
};
PCI: pci-bridge-emul: Create per-bridge copy of register behavior The behavior of the different registers of the PCI-to-PCI bridge is currently encoded in two global arrays, shared by all instances of PCI-to-PCI bridge emulation. However, we will need to tweak the behavior on a per-bridge basis, to accommodate for different capabilities of the platforms where this code is used. In preparation for this, create a per-bridge copy of the register behavior arrays, so that they can later be tweaked on a per-bridge basis. Fixes: 1f08673eef123 ("PCI: mvebu: Convert to PCI emulated bridge config space") Reported-by: Luís Mendes <luis.p.mendes@gmail.com> Reported-by: Leigh Brown <leigh@solinno.co.uk> Tested-by: Leigh Brown <leigh@solinno.co.uk> Tested-by: Luis Mendes <luis.p.mendes@gmail.com> Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Cc: stable@vger.kernel.org Cc: Luís Mendes <luis.p.mendes@gmail.com> Cc: Leigh Brown <leigh@solinno.co.uk>
2019-02-20 12:48:40 +03:00
struct pci_bridge_reg_behavior;
PCI: Introduce PCI bridge emulated config space common logic Some PCI host controllers do not expose a configuration space for the root port PCI bridge. Due to this, the Marvell Armada 370/38x/XP PCI controller driver (pci-mvebu) emulates a root port PCI bridge configuration space, and uses that to (among other things) dynamically create the memory windows that correspond to the PCI MEM and I/O regions. Since we now need to add a very similar logic for the Marvell Armada 37xx PCI controller driver (pci-aardvark), instead of duplicating the code, we create in this commit a common logic called pci-bridge-emul. The idea of this logic is to emulate a root port PCI bridge configuration space by providing configuration space read/write operations, and faking behind the scenes the configuration space of a PCI bridge. A PCI host controller driver simply has to call pci_bridge_emul_conf_read() and pci_bridge_emul_conf_write() to read/write the configuration space of the bridge. By default, the PCI bridge configuration space is simply emulated by a chunk of memory, but the PCI host controller can override the behavior of the read and write operations on a per-register basis to do additional actions if needed. We take care of complying with the behavior of the PCI configuration space registers in terms of bits that are read-write, read-only, reserved and write-1-to-clear. Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-10-18 18:37:16 +03:00
struct pci_bridge_emul {
struct pci_bridge_emul_conf conf;
struct pci_bridge_emul_pcie_conf pcie_conf;
struct pci_bridge_emul_ops *ops;
PCI: pci-bridge-emul: Create per-bridge copy of register behavior The behavior of the different registers of the PCI-to-PCI bridge is currently encoded in two global arrays, shared by all instances of PCI-to-PCI bridge emulation. However, we will need to tweak the behavior on a per-bridge basis, to accommodate for different capabilities of the platforms where this code is used. In preparation for this, create a per-bridge copy of the register behavior arrays, so that they can later be tweaked on a per-bridge basis. Fixes: 1f08673eef123 ("PCI: mvebu: Convert to PCI emulated bridge config space") Reported-by: Luís Mendes <luis.p.mendes@gmail.com> Reported-by: Leigh Brown <leigh@solinno.co.uk> Tested-by: Leigh Brown <leigh@solinno.co.uk> Tested-by: Luis Mendes <luis.p.mendes@gmail.com> Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Cc: stable@vger.kernel.org Cc: Luís Mendes <luis.p.mendes@gmail.com> Cc: Leigh Brown <leigh@solinno.co.uk>
2019-02-20 12:48:40 +03:00
struct pci_bridge_reg_behavior *pci_regs_behavior;
struct pci_bridge_reg_behavior *pcie_cap_regs_behavior;
PCI: Introduce PCI bridge emulated config space common logic Some PCI host controllers do not expose a configuration space for the root port PCI bridge. Due to this, the Marvell Armada 370/38x/XP PCI controller driver (pci-mvebu) emulates a root port PCI bridge configuration space, and uses that to (among other things) dynamically create the memory windows that correspond to the PCI MEM and I/O regions. Since we now need to add a very similar logic for the Marvell Armada 37xx PCI controller driver (pci-aardvark), instead of duplicating the code, we create in this commit a common logic called pci-bridge-emul. The idea of this logic is to emulate a root port PCI bridge configuration space by providing configuration space read/write operations, and faking behind the scenes the configuration space of a PCI bridge. A PCI host controller driver simply has to call pci_bridge_emul_conf_read() and pci_bridge_emul_conf_write() to read/write the configuration space of the bridge. By default, the PCI bridge configuration space is simply emulated by a chunk of memory, but the PCI host controller can override the behavior of the read and write operations on a per-register basis to do additional actions if needed. We take care of complying with the behavior of the PCI configuration space registers in terms of bits that are read-write, read-only, reserved and write-1-to-clear. Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-10-18 18:37:16 +03:00
void *data;
bool has_pcie;
};
PCI: pci-bridge-emul: Extend pci_bridge_emul_init() with flags Depending on the capabilities of the PCI controller/platform, the PCI-to-PCI bridge emulation behavior might need to be different. For example, on platforms that use the pci-mvebu code, we currently don't support prefetchable memory BARs, so the corresponding fields in the PCI-to-PCI bridge configuration space should be read-only. To implement this, extend pci_bridge_emul_init() to take a "flags" argument, with currently one flag supported: PCI_BRIDGE_EMUL_NO_PREFETCHABLE_BAR that will make the prefetchable memory base and limit registers read-only. The pci-mvebu and pci-aardvark drivers are updated accordingly. Fixes: 1f08673eef123 ("PCI: mvebu: Convert to PCI emulated bridge config space") Reported-by: Luís Mendes <luis.p.mendes@gmail.com> Reported-by: Leigh Brown <leigh@solinno.co.uk> Tested-by: Leigh Brown <leigh@solinno.co.uk> Tested-by: Luis Mendes <luis.p.mendes@gmail.com> Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Cc: stable@vger.kernel.org Cc: Luís Mendes <luis.p.mendes@gmail.com> Cc: Leigh Brown <leigh@solinno.co.uk>
2019-02-20 12:48:41 +03:00
enum {
PCI_BRIDGE_EMUL_NO_PREFETCHABLE_BAR = BIT(0),
};
int pci_bridge_emul_init(struct pci_bridge_emul *bridge,
unsigned int flags);
PCI: pci-bridge-emul: Create per-bridge copy of register behavior The behavior of the different registers of the PCI-to-PCI bridge is currently encoded in two global arrays, shared by all instances of PCI-to-PCI bridge emulation. However, we will need to tweak the behavior on a per-bridge basis, to accommodate for different capabilities of the platforms where this code is used. In preparation for this, create a per-bridge copy of the register behavior arrays, so that they can later be tweaked on a per-bridge basis. Fixes: 1f08673eef123 ("PCI: mvebu: Convert to PCI emulated bridge config space") Reported-by: Luís Mendes <luis.p.mendes@gmail.com> Reported-by: Leigh Brown <leigh@solinno.co.uk> Tested-by: Leigh Brown <leigh@solinno.co.uk> Tested-by: Luis Mendes <luis.p.mendes@gmail.com> Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Cc: stable@vger.kernel.org Cc: Luís Mendes <luis.p.mendes@gmail.com> Cc: Leigh Brown <leigh@solinno.co.uk>
2019-02-20 12:48:40 +03:00
void pci_bridge_emul_cleanup(struct pci_bridge_emul *bridge);
PCI: Introduce PCI bridge emulated config space common logic Some PCI host controllers do not expose a configuration space for the root port PCI bridge. Due to this, the Marvell Armada 370/38x/XP PCI controller driver (pci-mvebu) emulates a root port PCI bridge configuration space, and uses that to (among other things) dynamically create the memory windows that correspond to the PCI MEM and I/O regions. Since we now need to add a very similar logic for the Marvell Armada 37xx PCI controller driver (pci-aardvark), instead of duplicating the code, we create in this commit a common logic called pci-bridge-emul. The idea of this logic is to emulate a root port PCI bridge configuration space by providing configuration space read/write operations, and faking behind the scenes the configuration space of a PCI bridge. A PCI host controller driver simply has to call pci_bridge_emul_conf_read() and pci_bridge_emul_conf_write() to read/write the configuration space of the bridge. By default, the PCI bridge configuration space is simply emulated by a chunk of memory, but the PCI host controller can override the behavior of the read and write operations on a per-register basis to do additional actions if needed. We take care of complying with the behavior of the PCI configuration space registers in terms of bits that are read-write, read-only, reserved and write-1-to-clear. Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-10-18 18:37:16 +03:00
int pci_bridge_emul_conf_read(struct pci_bridge_emul *bridge, int where,
int size, u32 *value);
int pci_bridge_emul_conf_write(struct pci_bridge_emul *bridge, int where,
int size, u32 value);
#endif /* __PCI_BRIDGE_EMUL_H__ */
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