diff options
author | Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> | 2017-08-29 09:23:34 +0300 |
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committer | Michael Ellerman <mpe@ellerman.id.au> | 2017-08-31 07:26:30 +0300 |
commit | 180fe15a8299c14f77347c5835c98c2446226ee6 (patch) | |
tree | 6a8817e5eac206225a4aa8b5a261589b469d38fe /arch/powerpc/platforms/powernv/vas-window.c | |
parent | 4dea2d1a927c61114a168d4509b56329ea6effb7 (diff) | |
download | linux-180fe15a8299c14f77347c5835c98c2446226ee6.tar.xz |
powerpc/powernv/vas: Define helpers to access MMIO regions
Define some helper functions to access the MMIO regions. We use these
in follow-on patches to read/write VAS hardware registers. They are
also used to later issue 'paste' instructions to submit requests to
the NX hardware engines.
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc/platforms/powernv/vas-window.c')
-rw-r--r-- | arch/powerpc/platforms/powernv/vas-window.c | 174 |
1 files changed, 174 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/powernv/vas-window.c b/arch/powerpc/platforms/powernv/vas-window.c index de21acb62f30..642814a283eb 100644 --- a/arch/powerpc/platforms/powernv/vas-window.c +++ b/arch/powerpc/platforms/powernv/vas-window.c @@ -7,11 +7,185 @@ * 2 of the License, or (at your option) any later version. */ +#define pr_fmt(fmt) "vas: " fmt + #include <linux/types.h> #include <linux/mutex.h> +#include <linux/slab.h> +#include <linux/io.h> #include "vas.h" +/* + * Compute the paste address region for the window @window using the + * ->paste_base_addr and ->paste_win_id_shift we got from device tree. + */ +static void compute_paste_address(struct vas_window *window, u64 *addr, int *len) +{ + int winid; + u64 base, shift; + + base = window->vinst->paste_base_addr; + shift = window->vinst->paste_win_id_shift; + winid = window->winid; + + *addr = base + (winid << shift); + if (len) + *len = PAGE_SIZE; + + pr_debug("Txwin #%d: Paste addr 0x%llx\n", winid, *addr); +} + +static inline void get_hvwc_mmio_bar(struct vas_window *window, + u64 *start, int *len) +{ + u64 pbaddr; + + pbaddr = window->vinst->hvwc_bar_start; + *start = pbaddr + window->winid * VAS_HVWC_SIZE; + *len = VAS_HVWC_SIZE; +} + +static inline void get_uwc_mmio_bar(struct vas_window *window, + u64 *start, int *len) +{ + u64 pbaddr; + + pbaddr = window->vinst->uwc_bar_start; + *start = pbaddr + window->winid * VAS_UWC_SIZE; + *len = VAS_UWC_SIZE; +} + +/* + * Map the paste bus address of the given send window into kernel address + * space. Unlike MMIO regions (map_mmio_region() below), paste region must + * be mapped cache-able and is only applicable to send windows. + */ +void *map_paste_region(struct vas_window *txwin) +{ + int len; + void *map; + char *name; + u64 start; + + name = kasprintf(GFP_KERNEL, "window-v%d-w%d", txwin->vinst->vas_id, + txwin->winid); + if (!name) + goto free_name; + + txwin->paste_addr_name = name; + compute_paste_address(txwin, &start, &len); + + if (!request_mem_region(start, len, name)) { + pr_devel("%s(): request_mem_region(0x%llx, %d) failed\n", + __func__, start, len); + goto free_name; + } + + map = ioremap_cache(start, len); + if (!map) { + pr_devel("%s(): ioremap_cache(0x%llx, %d) failed\n", __func__, + start, len); + goto free_name; + } + + pr_devel("Mapped paste addr 0x%llx to kaddr 0x%p\n", start, map); + return map; + +free_name: + kfree(name); + return ERR_PTR(-ENOMEM); +} + + +static void *map_mmio_region(char *name, u64 start, int len) +{ + void *map; + + if (!request_mem_region(start, len, name)) { + pr_devel("%s(): request_mem_region(0x%llx, %d) failed\n", + __func__, start, len); + return NULL; + } + + map = ioremap(start, len); + if (!map) { + pr_devel("%s(): ioremap(0x%llx, %d) failed\n", __func__, start, + len); + return NULL; + } + + return map; +} + +static void unmap_region(void *addr, u64 start, int len) +{ + iounmap(addr); + release_mem_region((phys_addr_t)start, len); +} + +/* + * Unmap the paste address region for a window. + */ +void unmap_paste_region(struct vas_window *window) +{ + int len; + u64 busaddr_start; + + if (window->paste_kaddr) { + compute_paste_address(window, &busaddr_start, &len); + unmap_region(window->paste_kaddr, busaddr_start, len); + window->paste_kaddr = NULL; + kfree(window->paste_addr_name); + window->paste_addr_name = NULL; + } +} + +/* + * Unmap the MMIO regions for a window. + */ +static void unmap_winctx_mmio_bars(struct vas_window *window) +{ + int len; + u64 busaddr_start; + + if (window->hvwc_map) { + get_hvwc_mmio_bar(window, &busaddr_start, &len); + unmap_region(window->hvwc_map, busaddr_start, len); + window->hvwc_map = NULL; + } + + if (window->uwc_map) { + get_uwc_mmio_bar(window, &busaddr_start, &len); + unmap_region(window->uwc_map, busaddr_start, len); + window->uwc_map = NULL; + } +} + +/* + * Find the Hypervisor Window Context (HVWC) MMIO Base Address Region and the + * OS/User Window Context (UWC) MMIO Base Address Region for the given window. + * Map these bus addresses and save the mapped kernel addresses in @window. + */ +int map_winctx_mmio_bars(struct vas_window *window) +{ + int len; + u64 start; + + get_hvwc_mmio_bar(window, &start, &len); + window->hvwc_map = map_mmio_region("HVWCM_Window", start, len); + + get_uwc_mmio_bar(window, &start, &len); + window->uwc_map = map_mmio_region("UWCM_Window", start, len); + + if (!window->hvwc_map || !window->uwc_map) { + unmap_winctx_mmio_bars(window); + return -1; + } + + return 0; +} + /* stub for now */ int vas_win_close(struct vas_window *window) { |