alistair23-linux/include/linux/pci-epf.h
Kishon Vijay Abraham I 2a9a801620 PCI: endpoint: Add support to specify alignment for buffers allocated to BARs
The address that is allocated using pci_epf_alloc_space() is
directly written to the target address of the Inbound Address
Translation unit (ie the HW component implementing inbound address
decoding) on endpoint controllers.

Designware IP [1] has a configuration parameter (CX_ATU_MIN_REGION_SIZE
[2]) which has 64KB as default value and the lower 16 bits of the Base,
Limit and Target registers of the Inbound ATU are fixed to zero. If the
programmed memory address is not aligned to 64 KB boundary this causes
memory corruption.

Modify pci_epf_alloc_space() API to take alignment size as argument in
order to allocate buffers to be mapped to BARs with an alignment that
suits the platform where they are used.

Add an 'align' parameter to epc_features which can be used by platform
drivers to specify the BAR allocation alignment requirements and use
this while invoking pci_epf_alloc_space().

[1] "I/O and MEM Match Modes" section in DesignWare Cores PCI Express
     Controller Databook version 4.90a
[2]  http://www.ti.com/lit/ug/spruid7c/spruid7c.pdf

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
2019-04-15 13:24:02 +01:00

159 lines
4.8 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/**
* PCI Endpoint *Function* (EPF) header file
*
* Copyright (C) 2017 Texas Instruments
* Author: Kishon Vijay Abraham I <kishon@ti.com>
*/
#ifndef __LINUX_PCI_EPF_H
#define __LINUX_PCI_EPF_H
#include <linux/device.h>
#include <linux/mod_devicetable.h>
#include <linux/pci.h>
struct pci_epf;
enum pci_barno {
BAR_0,
BAR_1,
BAR_2,
BAR_3,
BAR_4,
BAR_5,
};
/**
* struct pci_epf_header - represents standard configuration header
* @vendorid: identifies device manufacturer
* @deviceid: identifies a particular device
* @revid: specifies a device-specific revision identifier
* @progif_code: identifies a specific register-level programming interface
* @subclass_code: identifies more specifically the function of the device
* @baseclass_code: broadly classifies the type of function the device performs
* @cache_line_size: specifies the system cacheline size in units of DWORDs
* @subsys_vendor_id: vendor of the add-in card or subsystem
* @subsys_id: id specific to vendor
* @interrupt_pin: interrupt pin the device (or device function) uses
*/
struct pci_epf_header {
u16 vendorid;
u16 deviceid;
u8 revid;
u8 progif_code;
u8 subclass_code;
u8 baseclass_code;
u8 cache_line_size;
u16 subsys_vendor_id;
u16 subsys_id;
enum pci_interrupt_pin interrupt_pin;
};
/**
* struct pci_epf_ops - set of function pointers for performing EPF operations
* @bind: ops to perform when a EPC device has been bound to EPF device
* @unbind: ops to perform when a binding has been lost between a EPC device
* and EPF device
* @linkup: ops to perform when the EPC device has established a connection with
* a host system
*/
struct pci_epf_ops {
int (*bind)(struct pci_epf *epf);
void (*unbind)(struct pci_epf *epf);
void (*linkup)(struct pci_epf *epf);
};
/**
* struct pci_epf_driver - represents the PCI EPF driver
* @probe: ops to perform when a new EPF device has been bound to the EPF driver
* @remove: ops to perform when the binding between the EPF device and EPF
* driver is broken
* @driver: PCI EPF driver
* @ops: set of function pointers for performing EPF operations
* @owner: the owner of the module that registers the PCI EPF driver
* @epf_group: list of configfs group corresponding to the PCI EPF driver
* @id_table: identifies EPF devices for probing
*/
struct pci_epf_driver {
int (*probe)(struct pci_epf *epf);
int (*remove)(struct pci_epf *epf);
struct device_driver driver;
struct pci_epf_ops *ops;
struct module *owner;
struct list_head epf_group;
const struct pci_epf_device_id *id_table;
};
#define to_pci_epf_driver(drv) (container_of((drv), struct pci_epf_driver, \
driver))
/**
* struct pci_epf_bar - represents the BAR of EPF device
* @phys_addr: physical address that should be mapped to the BAR
* @size: the size of the address space present in BAR
*/
struct pci_epf_bar {
dma_addr_t phys_addr;
size_t size;
enum pci_barno barno;
int flags;
};
/**
* struct pci_epf - represents the PCI EPF device
* @dev: the PCI EPF device
* @name: the name of the PCI EPF device
* @header: represents standard configuration header
* @bar: represents the BAR of EPF device
* @msi_interrupts: number of MSI interrupts required by this function
* @func_no: unique function number within this endpoint device
* @epc: the EPC device to which this EPF device is bound
* @driver: the EPF driver to which this EPF device is bound
* @list: to add pci_epf as a list of PCI endpoint functions to pci_epc
*/
struct pci_epf {
struct device dev;
const char *name;
struct pci_epf_header *header;
struct pci_epf_bar bar[6];
u8 msi_interrupts;
u16 msix_interrupts;
u8 func_no;
struct pci_epc *epc;
struct pci_epf_driver *driver;
struct list_head list;
};
#define to_pci_epf(epf_dev) container_of((epf_dev), struct pci_epf, dev)
#define pci_epf_register_driver(driver) \
__pci_epf_register_driver((driver), THIS_MODULE)
static inline void epf_set_drvdata(struct pci_epf *epf, void *data)
{
dev_set_drvdata(&epf->dev, data);
}
static inline void *epf_get_drvdata(struct pci_epf *epf)
{
return dev_get_drvdata(&epf->dev);
}
const struct pci_epf_device_id *
pci_epf_match_device(const struct pci_epf_device_id *id, struct pci_epf *epf);
struct pci_epf *pci_epf_create(const char *name);
void pci_epf_destroy(struct pci_epf *epf);
int __pci_epf_register_driver(struct pci_epf_driver *driver,
struct module *owner);
void pci_epf_unregister_driver(struct pci_epf_driver *driver);
void *pci_epf_alloc_space(struct pci_epf *epf, size_t size, enum pci_barno bar,
size_t align);
void pci_epf_free_space(struct pci_epf *epf, void *addr, enum pci_barno bar);
int pci_epf_bind(struct pci_epf *epf);
void pci_epf_unbind(struct pci_epf *epf);
void pci_epf_linkup(struct pci_epf *epf);
#endif /* __LINUX_PCI_EPF_H */