u-boot/include/lmb.h
Tom Rini 48fd7e9699 Merge patch series "Fix IOVA allocation in Apple dart iommu after global LMB mem map changes"
Janne Grunau <j@jannau.net> says:

The changes in "Make LMB memory map global and persistent" [1] break
mapping DMA memory in the USB xHCI driver when using the apple_dart
iommu present on Apple silicon systems.

The IOVA space used by the u-boot driver (low 4GB) and physical memory
do not overlap. The physical memory on this systems starts depending on
the SoC either at 0x10_0000_0000 or 0x100_0000_0000. It make no sense to
manage these distinct regions in a single LMB map. In addition every
device has its own iommu and IO address space so sharing a single memory
map between all iommu instances is not necessary.

To fix this issue restore the used subset (add, alloc and free) of the
previous pointer based LMB interface with "io_" as prefix.

To ensure that low level lmb functions do not use the global LMB
variable reorder lib/lmb.c so that the variable is not visible.

Tested with patches from my "Fix device removal order for Apple dart
iommu" series [2] to fix a separate issue.

The cosmetic commit has two checkpatch warnings in existing code which I
ignored.

[1] https://lore.kernel.org/u-boot/20240826115940.3233167-1-sughosh.ganu@linaro.org/
[2] https://lore.kernel.org/u-boot/20241031-iommu_apple_dart_ordering-v1-0-8a6877946d6b@jannau.net/

Link: https://lore.kernel.org/r/20241111-io_lmb_apple_dart_iommu-v3-0-32c05da51d72@jannau.net
Signed-off-by: Tom Rini <trini@konsulko.com>
2024-11-11 09:11:55 -06:00

213 lines
5.8 KiB
C

/* SPDX-License-Identifier: GPL-2.0+ */
#ifndef _LINUX_LMB_H
#define _LINUX_LMB_H
#ifdef __KERNEL__
#include <alist.h>
#include <asm/types.h>
#include <asm/u-boot.h>
#include <linux/bitops.h>
/*
* Logical memory blocks.
*
* Copyright (C) 2001 Peter Bergner, IBM Corp.
*/
#define LMB_ALLOC_ANYWHERE 0
#define LMB_ALIST_INITIAL_SIZE 4
/**
* enum lmb_flags - definition of memory region attributes
* @LMB_NONE: no special request
* @LMB_NOMAP: don't add to mmu configuration
* @LMB_NOOVERWRITE: the memory region cannot be overwritten/re-reserved
* @LMB_NONOTIFY: do not notify other modules of changes to this memory region
*/
enum lmb_flags {
LMB_NONE = 0,
LMB_NOMAP = BIT(1),
LMB_NOOVERWRITE = BIT(2),
LMB_NONOTIFY = BIT(3),
};
/**
* struct lmb_region - Description of one region.
*
* @base: Base address of the region.
* @size: Size of the region
* @flags: memory region attributes
*/
struct lmb_region {
phys_addr_t base;
phys_size_t size;
enum lmb_flags flags;
};
/**
* struct lmb - The LMB structure
*
* @free_mem: List of free memory regions
* @used_mem: List of used/reserved memory regions
* @test: Is structure being used for LMB tests
*/
struct lmb {
struct alist free_mem;
struct alist used_mem;
bool test;
};
/**
* lmb_init() - Initialise the LMB module
*
* Initialise the LMB lists needed for keeping the memory map. There
* are two lists, in form of alloced list data structure. One for the
* available memory, and one for the used memory. Initialise the two
* lists as part of board init. Add memory to the available memory
* list and reserve common areas by adding them to the used memory
* list.
*
* Return: 0 on success, -ve on error
*/
int lmb_init(void);
/**
* lmb_add_memory() - Add memory range for LMB allocations
*
* Add the entire available memory range to the pool of memory that
* can be used by the LMB module for allocations.
*
* Return: None
*/
void lmb_add_memory(void);
long lmb_add(phys_addr_t base, phys_size_t size);
long lmb_reserve(phys_addr_t base, phys_size_t size);
/**
* lmb_reserve_flags - Reserve one region with a specific flags bitfield.
*
* @base: base address of the memory region
* @size: size of the memory region
* @flags: flags for the memory region
* Return: 0 if OK, > 0 for coalesced region or a negative error code.
*/
long lmb_reserve_flags(phys_addr_t base, phys_size_t size,
enum lmb_flags flags);
phys_addr_t lmb_alloc(phys_size_t size, ulong align);
phys_addr_t lmb_alloc_base(phys_size_t size, ulong align, phys_addr_t max_addr);
phys_addr_t lmb_alloc_addr(phys_addr_t base, phys_size_t size);
phys_size_t lmb_get_free_size(phys_addr_t addr);
phys_addr_t lmb_alloc_base_flags(phys_size_t size, ulong align,
phys_addr_t max_addr, uint flags);
/**
* lmb_alloc_addr_flags() - Allocate specified memory address with specified attributes
* @base: Base Address requested
* @size: Size of the region requested
* @flags: Memory region attributes to be set
*
* Allocate a region of memory with the attributes specified through the
* parameter. The base parameter is used to specify the base address
* of the requested region.
*
* Return: base address on success, 0 on error
*/
phys_addr_t lmb_alloc_addr_flags(phys_addr_t base, phys_size_t size,
uint flags);
/**
* lmb_is_reserved_flags() - test if address is in reserved region with flag bits set
*
* The function checks if a reserved region comprising @addr exists which has
* all flag bits set which are set in @flags.
*
* @addr: address to be tested
* @flags: bitmap with bits to be tested
* Return: 1 if matching reservation exists, 0 otherwise
*/
int lmb_is_reserved_flags(phys_addr_t addr, int flags);
/**
* lmb_free_flags() - Free up a region of memory
* @base: Base Address of region to be freed
* @size: Size of the region to be freed
* @flags: Memory region attributes
*
* Free up a region of memory.
*
* Return: 0 if successful, -1 on failure
*/
long lmb_free_flags(phys_addr_t base, phys_size_t size, uint flags);
long lmb_free(phys_addr_t base, phys_size_t size);
void lmb_dump_all(void);
void lmb_dump_all_force(void);
void lmb_arch_add_memory(void);
struct lmb *lmb_get(void);
int lmb_push(struct lmb *store);
void lmb_pop(struct lmb *store);
static inline int lmb_read_check(phys_addr_t addr, phys_size_t len)
{
return lmb_alloc_addr(addr, len) == addr ? 0 : -1;
}
/**
* io_lmb_setup() - Initialize LMB struct
* @io_lmb: IO LMB to initialize
*
* Returns: 0 on success, negative error code on failure
*/
int io_lmb_setup(struct lmb *io_lmb);
/**
* io_lmb_teardown() - Tear LMB struct down
* @io_lmb: IO LMB to teardown
*/
void io_lmb_teardown(struct lmb *io_lmb);
/**
* io_lmb_add() - Add an IOVA range for allocations
* @io_lmb: LMB to add the space to
* @base: Base Address of region to add
* @size: Size of the region to add
*
* Add the IOVA space [base, base + size] to be managed by io_lmb.
*
* Returns: 0 if the region addition was successful, -1 on failure
*/
long io_lmb_add(struct lmb *io_lmb, phys_addr_t base, phys_size_t size);
/**
* io_lmb_alloc() - Allocate specified IO memory address with specified alignment
* @io_lmb: LMB to alloc from
* @size: Size of the region requested
* @align: Required address and size alignment
*
* Allocate a region of IO memory. The base parameter is used to specify the
* base address of the requested region.
*
* Return: base IO address on success, 0 on error
*/
phys_addr_t io_lmb_alloc(struct lmb *io_lmb, phys_size_t size, ulong align);
/**
* io_lmb_free() - Free up a region of IOVA space
* @io_lmb: LMB to return the IO address space to
* @base: Base Address of region to be freed
* @size: Size of the region to be freed
*
* Free up a region of IOVA space.
*
* Return: 0 if successful, -1 on failure
*/
long io_lmb_free(struct lmb *io_lmb, phys_addr_t base, phys_size_t size);
#endif /* __KERNEL__ */
#endif /* _LINUX_LMB_H */