/* SPDX-License-Identifier: GPL-2.0 */
/*
 * PCI Endpoint *Controller* (EPC) header file
 *
 * Copyright (C) 2017 Texas Instruments
 * Author: Kishon Vijay Abraham I <kishon@ti.com>
 */

#ifndef __LINUX_PCI_EPC_H
#define __LINUX_PCI_EPC_H

#include <linux/pci-epf.h>

struct pci_epc;

enum pci_epc_interface_type {
	UNKNOWN_INTERFACE = -1,
	PRIMARY_INTERFACE,
	SECONDARY_INTERFACE,
};

static inline const char *
pci_epc_interface_string(enum pci_epc_interface_type type)
{
	switch (type) {
	case PRIMARY_INTERFACE:
		return "primary";
	case SECONDARY_INTERFACE:
		return "secondary";
	default:
		return "UNKNOWN interface";
	}
}

/**
 * struct pci_epc_map - information about EPC memory for mapping a RC PCI
 *                      address range
 * @pci_addr: start address of the RC PCI address range to map
 * @pci_size: size of the RC PCI address range mapped from @pci_addr
 * @map_pci_addr: RC PCI address used as the first address mapped (may be lower
 *                than @pci_addr)
 * @map_size: size of the controller memory needed for mapping the RC PCI address
 *            range @map_pci_addr..@pci_addr+@pci_size
 * @phys_base: base physical address of the allocated EPC memory for mapping the
 *             RC PCI address range
 * @phys_addr: physical address at which @pci_addr is mapped
 * @virt_base: base virtual address of the allocated EPC memory for mapping the
 *             RC PCI address range
 * @virt_addr: virtual address at which @pci_addr is mapped
 */
struct pci_epc_map {
	u64		pci_addr;
	size_t		pci_size;

	u64		map_pci_addr;
	size_t		map_size;

	phys_addr_t	phys_base;
	phys_addr_t	phys_addr;
	void __iomem	*virt_base;
	void __iomem	*virt_addr;
};

/**
 * enum pci_epc_aux_resource_type - auxiliary resource type identifiers
 * @PCI_EPC_AUX_DOORBELL_MMIO: Doorbell MMIO, that might be outside the DMA
 *                             controller register window
 *
 * EPC backends may expose auxiliary blocks (e.g. DMA engines) by mapping their
 * register windows and descriptor memories into BAR space. This enum
 * identifies the type of each exposable resource.
 */
enum pci_epc_aux_resource_type {
	PCI_EPC_AUX_DOORBELL_MMIO,
};

/**
 * struct pci_epc_aux_resource - a physical auxiliary resource that may be
 *                               exposed for peer use
 * @type:       resource type, see enum pci_epc_aux_resource_type
 * @phys_addr:  physical base address of the resource
 * @size:       size of the resource in bytes
 * @bar:        BAR number where this resource is already exposed to the RC
 *              (NO_BAR if not)
 * @bar_offset: offset within @bar where the resource starts (valid iff
 *              @bar != NO_BAR)
 * @u:          type-specific metadata
 */
struct pci_epc_aux_resource {
	enum pci_epc_aux_resource_type type;
	phys_addr_t phys_addr;
	resource_size_t size;
	enum pci_barno bar;
	resource_size_t bar_offset;

	union {
		/* PCI_EPC_AUX_DOORBELL_MMIO */
		struct {
			int irq; /* IRQ number for the doorbell handler */
			u32 data; /* write value to ring the doorbell */
		} db_mmio;
	} u;
};

/**
 * struct pci_epc_ops - set of function pointers for performing EPC operations
 * @write_header: ops to populate configuration space header
 * @set_bar: ops to configure the BAR
 * @clear_bar: ops to reset the BAR
 * @align_addr: operation to get the mapping address, mapping size and offset
 *		into a controller memory window needed to map an RC PCI address
 *		region
 * @map_addr: ops to map CPU address to PCI address
 * @unmap_addr: ops to unmap CPU address and PCI address
 * @set_msi: ops to set the requested number of MSI interrupts in the MSI
 *	     capability register
 * @get_msi: ops to get the number of MSI interrupts allocated by the RC from
 *	     the MSI capability register
 * @set_msix: ops to set the requested number of MSI-X interrupts in the
 *	     MSI-X capability register
 * @get_msix: ops to get the number of MSI-X interrupts allocated by the RC
 *	     from the MSI-X capability register
 * @raise_irq: ops to raise a legacy, MSI or MSI-X interrupt
 * @map_msi_irq: ops to map physical address to MSI address and return MSI data
 * @start: ops to start the PCI link
 * @stop: ops to stop the PCI link
 * @get_features: ops to get the features supported by the EPC
 * @get_aux_resources_count: ops to get the number of controller-owned
 *                           auxiliary resources
 * @get_aux_resources: ops to retrieve controller-owned auxiliary resources
 * @owner: the module owner containing the ops
 */
struct pci_epc_ops {
	int	(*write_header)(struct pci_epc *epc, u8 func_no, u8 vfunc_no,
				struct pci_epf_header *hdr);
	int	(*set_bar)(struct pci_epc *epc, u8 func_no, u8 vfunc_no,
			   struct pci_epf_bar *epf_bar);
	void	(*clear_bar)(struct pci_epc *epc, u8 func_no, u8 vfunc_no,
			     struct pci_epf_bar *epf_bar);
	u64	(*align_addr)(struct pci_epc *epc, u64 pci_addr, size_t *size,
			      size_t *offset);
	int	(*map_addr)(struct pci_epc *epc, u8 func_no, u8 vfunc_no,
			    phys_addr_t addr, u64 pci_addr, size_t size);
	void	(*unmap_addr)(struct pci_epc *epc, u8 func_no, u8 vfunc_no,
			      phys_addr_t addr);
	int	(*set_msi)(struct pci_epc *epc, u8 func_no, u8 vfunc_no,
			   u8 nr_irqs);
	int	(*get_msi)(struct pci_epc *epc, u8 func_no, u8 vfunc_no);
	int	(*set_msix)(struct pci_epc *epc, u8 func_no, u8 vfunc_no,
			    u16 nr_irqs, enum pci_barno, u32 offset);
	int	(*get_msix)(struct pci_epc *epc, u8 func_no, u8 vfunc_no);
	int	(*raise_irq)(struct pci_epc *epc, u8 func_no, u8 vfunc_no,
			     unsigned int type, u16 interrupt_num);
	int	(*map_msi_irq)(struct pci_epc *epc, u8 func_no, u8 vfunc_no,
			       phys_addr_t phys_addr, u8 interrupt_num,
			       u32 entry_size, u32 *msi_data,
			       u32 *msi_addr_offset);
	int	(*start)(struct pci_epc *epc);
	void	(*stop)(struct pci_epc *epc);
	const struct pci_epc_features* (*get_features)(struct pci_epc *epc,
						       u8 func_no, u8 vfunc_no);
	int	(*get_aux_resources_count)(struct pci_epc *epc, u8 func_no,
					   u8 vfunc_no);
	int	(*get_aux_resources)(struct pci_epc *epc, u8 func_no, u8 vfunc_no,
				     struct pci_epc_aux_resource *resources,
				     int num_resources);
	struct module *owner;
};

/**
 * struct pci_epc_mem_window - address window of the endpoint controller
 * @phys_base: physical base address of the PCI address window
 * @size: the size of the PCI address window
 * @page_size: size of each page
 */
struct pci_epc_mem_window {
	phys_addr_t	phys_base;
	size_t		size;
	size_t		page_size;
};

/**
 * struct pci_epc_mem - address space of the endpoint controller
 * @window: address window of the endpoint controller
 * @bitmap: bitmap to manage the PCI address space
 * @pages: number of bits representing the address region
 * @lock: mutex to protect bitmap
 */
struct pci_epc_mem {
	struct pci_epc_mem_window window;
	unsigned long	*bitmap;
	int		pages;
	/* mutex to protect against concurrent access for memory allocation*/
	struct mutex	lock;
};

/**
 * struct pci_epc - represents the PCI EPC device
 * @dev: PCI EPC device
 * @pci_epf: list of endpoint functions present in this EPC device
 * @list_lock: Mutex for protecting pci_epf list
 * @ops: function pointers for performing endpoint operations
 * @windows: array of address space of the endpoint controller
 * @mem: first window of the endpoint controller, which corresponds to
 *       default address space of the endpoint controller supporting
 *       single window.
 * @num_windows: number of windows supported by device
 * @max_functions: max number of functions that can be configured in this EPC
 * @max_vfs: Array indicating the maximum number of virtual functions that can
 *   be associated with each physical function
 * @group: configfs group representing the PCI EPC device
 * @lock: mutex to protect pci_epc ops
 * @function_num_map: bitmap to manage physical function number
 * @domain_nr: PCI domain number of the endpoint controller
 * @init_complete: flag to indicate whether the EPC initialization is complete
 *                 or not
 */
struct pci_epc {
	struct device			dev;
	struct list_head		pci_epf;
	struct mutex			list_lock;
	const struct pci_epc_ops	*ops;
	struct pci_epc_mem		**windows;
	struct pci_epc_mem		*mem;
	unsigned int			num_windows;
	u8				max_functions;
	u8				*max_vfs;
	struct config_group		*group;
	/* mutex to protect against concurrent access of EP controller */
	struct mutex			lock;
	unsigned long			function_num_map;
	int				domain_nr;
	bool				init_complete;
};

/**
 * enum pci_epc_bar_type - configurability of endpoint BAR
 * @BAR_PROGRAMMABLE: The BAR mask can be configured by the EPC.
 * @BAR_FIXED: The BAR mask is fixed by the hardware.
 * @BAR_RESIZABLE: The BAR implements the PCI-SIG Resizable BAR Capability.
 *		   NOTE: An EPC driver can currently only set a single supported
 *		   size.
 * @BAR_RESERVED: Used for HW-backed BARs (e.g. MSI-X table, DMA regs). The BAR
 *		  should not be disabled by an EPC driver. The BAR should not be
 *		  reprogrammed by an EPF driver. An EPF driver is allowed to
 *		  disable the BAR if absolutely necessary. (However, right now
 *		  there is no EPC operation to disable a BAR that has not been
 *		  programmed using pci_epc_set_bar().)
 * @BAR_DISABLED: The BAR should be disabled by an EPC driver. The BAR will be
 *		  unavailable to an EPF driver.
 */
enum pci_epc_bar_type {
	BAR_PROGRAMMABLE = 0,
	BAR_FIXED,
	BAR_RESIZABLE,
	BAR_RESERVED,
	BAR_DISABLED,
};

/**
 * enum pci_epc_bar_rsvd_region_type - type of a fixed subregion behind a BAR
 * @PCI_EPC_BAR_RSVD_DMA_CTRL_MMIO: Integrated DMA controller MMIO window
 * @PCI_EPC_BAR_RSVD_MSIX_TBL_RAM: MSI-X table structure
 * @PCI_EPC_BAR_RSVD_MSIX_PBA_RAM: MSI-X PBA structure
 *
 * BARs marked BAR_RESERVED are owned by the SoC/EPC hardware and must not be
 * reprogrammed by EPF drivers. Some of them still expose fixed subregions that
 * EPFs may want to reference (e.g. embedded doorbell fallback).
 */
enum pci_epc_bar_rsvd_region_type {
	PCI_EPC_BAR_RSVD_DMA_CTRL_MMIO = 0,
	PCI_EPC_BAR_RSVD_MSIX_TBL_RAM,
	PCI_EPC_BAR_RSVD_MSIX_PBA_RAM,
};

/**
 * struct pci_epc_bar_rsvd_region - fixed subregion behind a BAR
 * @type: reserved region type
 * @offset: offset within the BAR aperture
 * @size: size of the reserved region
 */
struct pci_epc_bar_rsvd_region {
	enum pci_epc_bar_rsvd_region_type	type;
	resource_size_t				offset;
	resource_size_t				size;
};

/**
 * struct pci_epc_bar_desc - hardware description for a BAR
 * @type: the type of the BAR
 * @fixed_size: the fixed size, only applicable if type is BAR_FIXED_MASK.
 * @only_64bit: if true, an EPF driver is not allowed to choose if this BAR
 *		should be configured as 32-bit or 64-bit, the EPF driver must
 *		configure this BAR as 64-bit.
 * @nr_rsvd_regions: number of fixed subregions described for BAR_RESERVED
 * @rsvd_regions: fixed subregions behind BAR_RESERVED
 */
struct pci_epc_bar_desc {
	enum pci_epc_bar_type type;
	u64 fixed_size;
	bool only_64bit;
	u8 nr_rsvd_regions;
	const struct pci_epc_bar_rsvd_region *rsvd_regions;
};

/**
 * struct pci_epc_features - features supported by a EPC device per function
 * @linkup_notifier: indicate if the EPC device can notify EPF driver on link up
 * @dynamic_inbound_mapping: indicate if the EPC device supports updating
 *                           inbound mappings for an already configured BAR
 *                           (i.e. allow calling pci_epc_set_bar() again
 *                           without first calling pci_epc_clear_bar())
 * @subrange_mapping: indicate if the EPC device can map inbound subranges for a
 *                    BAR. This feature depends on @dynamic_inbound_mapping
 *                    feature.
 * @msi_capable: indicate if the endpoint function has MSI capability
 * @msix_capable: indicate if the endpoint function has MSI-X capability
 * @intx_capable: indicate if the endpoint can raise INTx interrupts
 * @bar: array specifying the hardware description for each BAR
 * @align: alignment size required for BAR buffer allocation
 */
struct pci_epc_features {
	unsigned int	linkup_notifier : 1;
	unsigned int	dynamic_inbound_mapping : 1;
	unsigned int	subrange_mapping : 1;
	unsigned int	msi_capable : 1;
	unsigned int	msix_capable : 1;
	unsigned int	intx_capable : 1;
	struct	pci_epc_bar_desc bar[PCI_STD_NUM_BARS];
	size_t	align;
};

#define to_pci_epc(device) container_of((device), struct pci_epc, dev)

#ifdef CONFIG_PCI_ENDPOINT

#define pci_epc_create(dev, ops)    \
		__pci_epc_create((dev), (ops), THIS_MODULE)
#define devm_pci_epc_create(dev, ops)    \
		__devm_pci_epc_create((dev), (ops), THIS_MODULE)

static inline void epc_set_drvdata(struct pci_epc *epc, void *data)
{
	dev_set_drvdata(&epc->dev, data);
}

static inline void *epc_get_drvdata(struct pci_epc *epc)
{
	return dev_get_drvdata(&epc->dev);
}

struct pci_epc *
__devm_pci_epc_create(struct device *dev, const struct pci_epc_ops *ops,
		      struct module *owner);
struct pci_epc *
__pci_epc_create(struct device *dev, const struct pci_epc_ops *ops,
		 struct module *owner);
void pci_epc_destroy(struct pci_epc *epc);
int pci_epc_add_epf(struct pci_epc *epc, struct pci_epf *epf,
		    enum pci_epc_interface_type type);
void pci_epc_linkup(struct pci_epc *epc);
void pci_epc_linkdown(struct pci_epc *epc);
void pci_epc_init_notify(struct pci_epc *epc);
void pci_epc_notify_pending_init(struct pci_epc *epc, struct pci_epf *epf);
void pci_epc_deinit_notify(struct pci_epc *epc);
void pci_epc_bus_master_enable_notify(struct pci_epc *epc);
void pci_epc_remove_epf(struct pci_epc *epc, struct pci_epf *epf,
			enum pci_epc_interface_type type);
int pci_epc_write_header(struct pci_epc *epc, u8 func_no, u8 vfunc_no,
			 struct pci_epf_header *hdr);
int pci_epc_bar_size_to_rebar_cap(size_t size, u32 *cap);
int pci_epc_set_bar(struct pci_epc *epc, u8 func_no, u8 vfunc_no,
		    struct pci_epf_bar *epf_bar);
void pci_epc_clear_bar(struct pci_epc *epc, u8 func_no, u8 vfunc_no,
		       struct pci_epf_bar *epf_bar);
int pci_epc_map_addr(struct pci_epc *epc, u8 func_no, u8 vfunc_no,
		     phys_addr_t phys_addr,
		     u64 pci_addr, size_t size);
void pci_epc_unmap_addr(struct pci_epc *epc, u8 func_no, u8 vfunc_no,
			phys_addr_t phys_addr);
int pci_epc_set_msi(struct pci_epc *epc, u8 func_no, u8 vfunc_no, u8 nr_irqs);
int pci_epc_get_msi(struct pci_epc *epc, u8 func_no, u8 vfunc_no);
int pci_epc_set_msix(struct pci_epc *epc, u8 func_no, u8 vfunc_no, u16 nr_irqs,
		     enum pci_barno, u32 offset);
int pci_epc_get_msix(struct pci_epc *epc, u8 func_no, u8 vfunc_no);
int pci_epc_map_msi_irq(struct pci_epc *epc, u8 func_no, u8 vfunc_no,
			phys_addr_t phys_addr, u8 interrupt_num,
			u32 entry_size, u32 *msi_data, u32 *msi_addr_offset);
int pci_epc_raise_irq(struct pci_epc *epc, u8 func_no, u8 vfunc_no,
		      unsigned int type, u16 interrupt_num);
int pci_epc_start(struct pci_epc *epc);
void pci_epc_stop(struct pci_epc *epc);
const struct pci_epc_features *pci_epc_get_features(struct pci_epc *epc,
						    u8 func_no, u8 vfunc_no);
int pci_epc_get_aux_resources_count(struct pci_epc *epc, u8 func_no,
				    u8 vfunc_no);
int pci_epc_get_aux_resources(struct pci_epc *epc, u8 func_no, u8 vfunc_no,
			      struct pci_epc_aux_resource *resources,
			      int num_resources);
enum pci_barno
pci_epc_get_first_free_bar(const struct pci_epc_features *epc_features);
enum pci_barno pci_epc_get_next_free_bar(const struct pci_epc_features
					 *epc_features, enum pci_barno bar);
struct pci_epc *pci_epc_get(const char *epc_name);
void pci_epc_put(struct pci_epc *epc);

int pci_epc_mem_init(struct pci_epc *epc, phys_addr_t base,
		     size_t size, size_t page_size);
int pci_epc_multi_mem_init(struct pci_epc *epc,
			   struct pci_epc_mem_window *window,
			   unsigned int num_windows);
void pci_epc_mem_exit(struct pci_epc *epc);
void __iomem *pci_epc_mem_alloc_addr(struct pci_epc *epc,
				     phys_addr_t *phys_addr, size_t size);
void pci_epc_mem_free_addr(struct pci_epc *epc, phys_addr_t phys_addr,
			   void __iomem *virt_addr, size_t size);
int pci_epc_mem_map(struct pci_epc *epc, u8 func_no, u8 vfunc_no,
		    u64 pci_addr, size_t pci_size, struct pci_epc_map *map);
void pci_epc_mem_unmap(struct pci_epc *epc, u8 func_no, u8 vfunc_no,
		       struct pci_epc_map *map);

#else
static inline void pci_epc_init_notify(struct pci_epc *epc)
{
}

static inline void pci_epc_deinit_notify(struct pci_epc *epc)
{
}
#endif /* CONFIG_PCI_ENDPOINT */
#endif /* __LINUX_PCI_EPC_H */
