Hi Prabhakar,
On 08/01/20 9:52 PM, Lad Prabhakar wrote:
> R-Car PCIe controller has support to map multiple memory regions for
> mapping the outbound memory in local system also the controller limits
> single allocation for each region (that is, once a chunk is used from the
> region it cannot be used to allocate a new one). This features inspires to
> add support for handling multiple memory bases in endpoint framework.
>
> With this patch pci_epc_mem_init() now accepts multiple regions, also
> page_size for each memory region is passed during initialization so as
> to handle single allocation for each region by setting the page_size to
> window_size.
>
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
> ---
> .../pci/controller/cadence/pcie-cadence-ep.c | 12 +-
> .../pci/controller/dwc/pcie-designware-ep.c | 31 ++-
> drivers/pci/controller/pcie-rockchip-ep.c | 14 +-
> drivers/pci/endpoint/functions/pci-epf-test.c | 29 +--
> drivers/pci/endpoint/pci-epc-core.c | 7 +-
> drivers/pci/endpoint/pci-epc-mem.c | 199 ++++++++++++++----
> include/linux/pci-epc.h | 46 ++--
> 7 files changed, 245 insertions(+), 93 deletions(-)
>
.
.
<snip>
.
.
> diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c
> index 2091508c1620..289c266c2d90 100644
> --- a/drivers/pci/endpoint/pci-epc-core.c
> +++ b/drivers/pci/endpoint/pci-epc-core.c
> @@ -358,13 +358,15 @@ EXPORT_SYMBOL_GPL(pci_epc_unmap_addr);
> * @epc: the EPC device on which address is allocated
> * @func_no: the endpoint function number in the EPC device
> * @phys_addr: physical address of the local system
> + * @window: index to the window region where PCI address will be mapped
> * @pci_addr: PCI address to which the physical address should be mapped
> * @size: the size of the allocation
> *
> * Invoke to map CPU address with PCI address.
> */
> int pci_epc_map_addr(struct pci_epc *epc, u8 func_no,
> - phys_addr_t phys_addr, u64 pci_addr, size_t size)
> + phys_addr_t phys_addr, int window,
> + u64 pci_addr, size_t size)
> {
> int ret;
> unsigned long flags;
> @@ -376,7 +378,8 @@ int pci_epc_map_addr(struct pci_epc *epc, u8 func_no,
> return 0;
>
> spin_lock_irqsave(&epc->lock, flags);
> - ret = epc->ops->map_addr(epc, func_no, phys_addr, pci_addr, size);
> + ret = epc->ops->map_addr(epc, func_no, phys_addr,
> + window, pci_addr, size);
> spin_unlock_irqrestore(&epc->lock, flags);
>
> return ret;
> diff --git a/drivers/pci/endpoint/pci-epc-mem.c b/drivers/pci/endpoint/pci-epc-mem.c
> index d2b174ce15de..f205f7819292 100644
> --- a/drivers/pci/endpoint/pci-epc-mem.c
> +++ b/drivers/pci/endpoint/pci-epc-mem.c
> @@ -38,57 +38,77 @@ static int pci_epc_mem_get_order(struct pci_epc_mem *mem, size_t size)
> /**
> * __pci_epc_mem_init() - initialize the pci_epc_mem structure
> * @epc: the EPC device that invoked pci_epc_mem_init
> - * @phys_base: the physical address of the base
> - * @size: the size of the address space
> - * @page_size: size of each page
> + * @windows: pointer to windows supported by the device
> + * @num_windows: number of windows device supports
> *
> * Invoke to initialize the pci_epc_mem structure used by the
> * endpoint functions to allocate mapped PCI address.
> */
> -int __pci_epc_mem_init(struct pci_epc *epc, phys_addr_t phys_base, size_t size,
> - size_t page_size)
> +int __pci_epc_mem_init(struct pci_epc *epc, struct pci_epc_mem_window *windows,
> + int num_windows)
> {
> - int ret;
> - struct pci_epc_mem *mem;
> - unsigned long *bitmap;
> + struct pci_epc_mem *mem = NULL;
> + unsigned long *bitmap = NULL;
> unsigned int page_shift;
> - int pages;
> + size_t page_size;
> int bitmap_size;
> + int pages;
> + int ret;
> + int i;
>
> - if (page_size < PAGE_SIZE)
> - page_size = PAGE_SIZE;
> + epc->mem_windows = 0;
>
> - page_shift = ilog2(page_size);
> - pages = size >> page_shift;
> - bitmap_size = BITS_TO_LONGS(pages) * sizeof(long);
> + if (!windows)
> + return -EINVAL;
>
> - mem = kzalloc(sizeof(*mem), GFP_KERNEL);
> - if (!mem) {
> - ret = -ENOMEM;
> - goto err;
> - }
> + if (num_windows <= 0)
> + return -EINVAL;
>
> - bitmap = kzalloc(bitmap_size, GFP_KERNEL);
> - if (!bitmap) {
> - ret = -ENOMEM;
> - goto err_mem;
> - }
> + epc->mem = kcalloc(num_windows, sizeof(*mem), GFP_KERNEL);
> + if (!epc->mem)
> + return -EINVAL;
> +
> + for (i = 0; i < num_windows; i++) {
> + page_size = windows[i].page_size;
> + if (page_size < PAGE_SIZE)
> + page_size = PAGE_SIZE;
> + page_shift = ilog2(page_size);
> + pages = windows[i].size >> page_shift;
> + bitmap_size = BITS_TO_LONGS(pages) * sizeof(long);
> +
> + mem = kzalloc(sizeof(*mem), GFP_KERNEL);
> + if (!mem) {
> + ret = -ENOMEM;
> + goto err_mem;
> + }
>
> - mem->bitmap = bitmap;
> - mem->phys_base = phys_base;
> - mem->page_size = page_size;
> - mem->pages = pages;
> - mem->size = size;
> + bitmap = kzalloc(bitmap_size, GFP_KERNEL);
> + if (!bitmap) {
> + ret = -ENOMEM;
> + goto err_mem;
> + }
>
> - epc->mem = mem;
> + mem->bitmap = bitmap;
> + mem->window.phys_base = windows[i].phys_base;
> + mem->page_size = page_size;
> + mem->pages = pages;
> + mem->window.size = windows[i].size;
> + mem->window.map_size = 0;
> +
> + epc->mem[i] = mem;
> + }
> + epc->mem_windows = num_windows;
>
> return 0;
>
> err_mem:
> - kfree(mem);
> + for (; i >= 0; i--) {
mem has to be reinitialized for every iteration of the loop.
> + kfree(mem->bitmap);
> + kfree(epc->mem[i]);
> + }
> + kfree(epc->mem);
>
> -err:
> -return ret;
> + return ret;
> }
> EXPORT_SYMBOL_GPL(__pci_epc_mem_init);
>
> @@ -101,48 +121,127 @@ EXPORT_SYMBOL_GPL(__pci_epc_mem_init);
> */
> void pci_epc_mem_exit(struct pci_epc *epc)
> {
> - struct pci_epc_mem *mem = epc->mem;
> + struct pci_epc_mem *mem;
> + int i;
> +
> + if (!epc->mem_windows)
> + return;
> +
> + for (i = 0; i <= epc->mem_windows; i++) {
> + mem = epc->mem[i];
> + kfree(mem->bitmap);
> + kfree(epc->mem[i]);
> + }
> + kfree(epc->mem);
>
> epc->mem = NULL;
> - kfree(mem->bitmap);
> - kfree(mem);
> + epc->mem_windows = 0;
> }
> EXPORT_SYMBOL_GPL(pci_epc_mem_exit);
>
> +static int pci_epc_find_best_fit_window(struct pci_epc *epc, size_t size)
> +{
> + size_t window_least_size = 0;
> + int best_fit_window = -1;
> + struct pci_epc_mem *mem;
> + size_t actual_size;
> + size_t avail_size;
> + int i;
> +
> + for (i = 0; i < epc->mem_windows; i++) {
> + mem = epc->mem[i];
> +
> + actual_size = ALIGN(size, mem->page_size);
> + avail_size = mem->window.size - mem->window.map_size;
> +
> + if (best_fit_window == -1) {
> + if (actual_size <= avail_size) {
> + best_fit_window = i;
> + window_least_size = mem->window.size;
> + }
> + } else {
> + if (actual_size <= avail_size &&
> + mem->window.size < window_least_size) {
> + best_fit_window = i;
> + window_least_size = mem->window.size;
> + }
> + }
> + }
> +
> + return best_fit_window;
> +}
This function shouldn't be required at all. Just loop over all the
windows invoking bitmap_find_free_region(), breaking the loop if it
succeeds and continuing if there is no free region.
> +
> /**
> * pci_epc_mem_alloc_addr() - allocate memory address from EPC addr space
> * @epc: the EPC device on which memory has to be allocated
> * @phys_addr: populate the allocated physical address here
> + * @window: populate the window here which will be used to map PCI address
> * @size: the size of the address space that has to be allocated
> *
> * Invoke to allocate memory address from the EPC address space. This
> * is usually done to map the remote RC address into the local system.
> */
> void __iomem *pci_epc_mem_alloc_addr(struct pci_epc *epc,
> - phys_addr_t *phys_addr, size_t size)
> + phys_addr_t *phys_addr,
> + int *window, size_t size)
> {
> + int best_fit = PCI_EPC_DEFAULT_WINDOW;
> + void __iomem *virt_addr = NULL;
> + struct pci_epc_mem *mem;
> + unsigned int page_shift;
> int pageno;
> - void __iomem *virt_addr;
> - struct pci_epc_mem *mem = epc->mem;
> - unsigned int page_shift = ilog2(mem->page_size);
> int order;
>
> + if (epc->mem_windows <= 0)
> + return NULL;
> +
> + if (epc->mem_windows > 1) {
> + best_fit = pci_epc_find_best_fit_window(epc, size);
> + if (best_fit < 0)
> + return NULL;
> + }
> +
> + mem = epc->mem[best_fit];
> size = ALIGN(size, mem->page_size);
> + if (size > (mem->window.size - mem->window.map_size))
> + return NULL;
> + page_shift = ilog2(mem->page_size);
> order = pci_epc_mem_get_order(mem, size);
>
> pageno = bitmap_find_free_region(mem->bitmap, mem->pages, order);
> if (pageno < 0)
> return NULL;
This has to be invoked now in a loop for the number of windows. If
pageno < 0, continue the loop or else break.
>
> - *phys_addr = mem->phys_base + ((phys_addr_t)pageno << page_shift);
> + *phys_addr = mem->window.phys_base +
> + ((phys_addr_t)pageno << page_shift);
> virt_addr = ioremap(*phys_addr, size);
> - if (!virt_addr)
> + if (!virt_addr) {
> bitmap_release_region(mem->bitmap, pageno, order);
> + } else {
> + mem->window.map_size += size;
The map_size shouldn't be required.
> + *window = best_fit;
Can't the platform driver get the window based on the address? Let's try
to avoid modifying API's for platform specific requirements.
> + }
>
> return virt_addr;
> }
> EXPORT_SYMBOL_GPL(pci_epc_mem_alloc_addr);
>
> +static int pci_epc_get_matching_window(struct pci_epc *epc,
> + phys_addr_t phys_addr)
> +{
> + struct pci_epc_mem *mem;
> + int i;
> +
> + for (i = 0; i < epc->mem_windows; i++) {
> + mem = epc->mem[i];
> +
> + if (mem->window.phys_base == phys_addr)
> + return i;
> + }
> +
> + return -EINVAL;
> +}
> +
> /**
> * pci_epc_mem_free_addr() - free the allocated memory address
> * @epc: the EPC device on which memory was allocated
> @@ -155,16 +254,26 @@ EXPORT_SYMBOL_GPL(pci_epc_mem_alloc_addr);
> void pci_epc_mem_free_addr(struct pci_epc *epc, phys_addr_t phys_addr,
> void __iomem *virt_addr, size_t size)
> {
> + struct pci_epc_mem *mem;
> + unsigned int page_shift;
> + int window = 0;
> int pageno;
> - struct pci_epc_mem *mem = epc->mem;
> - unsigned int page_shift = ilog2(mem->page_size);
> int order;
>
> + if (epc->mem_windows > 1) {
> + window = pci_epc_get_matching_window(epc, phys_addr);
> + if (window < 0)
> + return;
> + }
> +
> + mem = epc->mem[window];
> + page_shift = ilog2(mem->page_size);
> iounmap(virt_addr);
> - pageno = (phys_addr - mem->phys_base) >> page_shift;
> + pageno = (phys_addr - mem->window.phys_base) >> page_shift;
> size = ALIGN(size, mem->page_size);
> order = pci_epc_mem_get_order(mem, size);
> bitmap_release_region(mem->bitmap, pageno, order);
> + mem->window.map_size -= size;
> }
> EXPORT_SYMBOL_GPL(pci_epc_mem_free_addr);
>
> diff --git a/include/linux/pci-epc.h b/include/linux/pci-epc.h
> index 56f1846b9d39..89daafa0d19f 100644
> --- a/include/linux/pci-epc.h
> +++ b/include/linux/pci-epc.h
> @@ -48,7 +48,8 @@ struct pci_epc_ops {
> void (*clear_bar)(struct pci_epc *epc, u8 func_no,
> struct pci_epf_bar *epf_bar);
> int (*map_addr)(struct pci_epc *epc, u8 func_no,
> - phys_addr_t addr, u64 pci_addr, size_t size);
> + phys_addr_t addr, int window,
> + u64 pci_addr, size_t size);
> void (*unmap_addr)(struct pci_epc *epc, u8 func_no,
> phys_addr_t addr);
> int (*set_msi)(struct pci_epc *epc, u8 func_no, u8 interrupts);
> @@ -64,17 +65,31 @@ struct pci_epc_ops {
> struct module *owner;
> };
>
> +#define PCI_EPC_DEFAULT_WINDOW 0
> +
> +/**
> + * 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
> + * @map_size: size of allocated chunk in window
> + * @page_size: size of each page
> + */
> +struct pci_epc_mem_window {
> + phys_addr_t phys_base;
> + size_t size;
> + size_t map_size;
mem->bitmap already holds the map_size information. This structure can
be used only for passing info about the mem windows from platform to the
core. So map_size shouldn't be required.
Thanks
Kishon
