From de9a65e8c7d73974816d715c0485e2756848ae5f Mon Sep 17 00:00:00 2001 From: "Suren A. Chilingaryan" Date: Thu, 7 May 2015 05:02:46 +0200 Subject: Provide PCIe link information in pcilib --- pcilib/pci.c | 112 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++-- pcilib/pci.h | 13 ++++++- 2 files changed, 122 insertions(+), 3 deletions(-) (limited to 'pcilib') diff --git a/pcilib/pci.c b/pcilib/pci.c index a9cefda..3a18ccd 100644 --- a/pcilib/pci.c +++ b/pcilib/pci.c @@ -11,6 +11,8 @@ #include #include #include +#include +#include #include #include #include @@ -106,6 +108,7 @@ pcilib_t *pcilib_open(const char *device, const char *model) { if (ctx) { memset(ctx, 0, sizeof(pcilib_t)); + ctx->pci_cfg_space_fd = -1; ctx->handle = open(device, O_RDWR); if (ctx->handle < 0) { @@ -197,6 +200,7 @@ pcilib_context_t *pcilib_get_implementation_context(pcilib_t *ctx) { return ctx->event_ctx; } + int pcilib_map_data_space(pcilib_t *ctx, uintptr_t addr) { int err; pcilib_bar_t i; @@ -211,7 +215,7 @@ int pcilib_map_data_space(pcilib_t *ctx, uintptr_t addr) { return err; } - int data_bar = -1; + int data_bar = -1; for (i = 0; i < PCILIB_MAX_BARS; i++) { if ((ctx->bar_space[i])||(!board_info->bar_length[i])) continue; @@ -255,7 +259,7 @@ int pcilib_map_data_space(pcilib_t *ctx, uintptr_t addr) { return 0; } -char *pcilib_resolve_register_address(pcilib_t *ctx, pcilib_bar_t bar, uintptr_t addr) { +char *pcilib_resolve_register_address(pcilib_t *ctx, pcilib_bar_t bar, uintptr_t addr) { if (bar == PCILIB_BAR_DETECT) { // First checking the default register bar size_t offset = addr - ctx->board_info.bar_start[ctx->reg_bar]; @@ -347,6 +351,9 @@ void pcilib_close(pcilib_t *ctx) { pcilib_unmap_bar(ctx, i, ptr); } } + + if (ctx->pci_cfg_space_fd >= 0) + close(ctx->pci_cfg_space_fd); if (ctx->registers) free(ctx->registers); @@ -361,3 +368,104 @@ void pcilib_close(pcilib_t *ctx) { } } +static int pcilib_update_pci_configuration_space(pcilib_t *ctx) { + int err; + int size; + + if (ctx->pci_cfg_space_fd < 0) { + char fname[128]; + + const pcilib_board_info_t *board_info = pcilib_get_board_info(ctx); + if (!board_info) { + pcilib_error("Failed to acquire board info"); + return PCILIB_ERROR_FAILED; + } + + sprintf(fname, "/sys/bus/pci/devices/0000:%02x:%02x.%1x/config", board_info->bus, board_info->slot, board_info->func); + + ctx->pci_cfg_space_fd = open(fname, O_RDONLY); + if (ctx->pci_cfg_space_fd < 0) { + pcilib_error("Failed to open configuration space in %s", fname); + return PCILIB_ERROR_FAILED; + } + } else { + err = lseek(ctx->pci_cfg_space_fd, SEEK_SET, 0); + if (err) { + close(ctx->pci_cfg_space_fd); + ctx->pci_cfg_space_fd = -1; + return pcilib_update_pci_configuration_space(ctx); + } + } + + size = read(ctx->pci_cfg_space_fd, ctx->pci_cfg_space_cache, 256); + if (size != 256) { + pcilib_error("Failed to read PCI configuration from sysfs"); + return PCILIB_ERROR_FAILED; + } + + return 0; +} + + +static uint32_t *pcilib_get_pci_capabilities(pcilib_t *ctx, int cap_id) { + int err; + + uint32_t cap; + uint8_t cap_offset; /**< Offset of capability in the configuration space */ + + if (!ctx->pci_cfg_space_fd) { + err = pcilib_update_pci_configuration_space(ctx); + if (err) { + pcilib_error("Error (%i) reading PCI configuration space", err); + return NULL; + } + } + + // This is just a pointer to the first cap + cap = ctx->pci_cfg_space_cache[(0x34>>2)]; + cap_offset = cap&0xFC; + + while ((cap_offset)&&(cap_offset < 256)) { + cap = ctx->pci_cfg_space_cache[cap_offset>>2]; + if ((cap&0xFF) == cap_id) + return &ctx->pci_cfg_space_cache[cap_offset>>2]; + cap_offset = (cap>>8)&0xFC; + } + + return NULL; +}; + + +static const uint32_t *pcilib_get_pcie_capabilities(pcilib_t *ctx) { + if (ctx->pcie_capabilities) + return ctx->pcie_capabilities; + + ctx->pcie_capabilities = pcilib_get_pci_capabilities(ctx, 0x10); + return ctx->pcie_capabilities; +} + + +const pcilib_pcie_link_info_t *pcilib_get_pcie_link_info(pcilib_t *ctx) { + int err; + const uint32_t *cap; + + err = pcilib_update_pci_configuration_space(ctx); + if (err) { + pcilib_error("Error (%i) updating PCI configuration space", err); + return NULL; + } + + cap = pcilib_get_pcie_capabilities(ctx); + if (!cap) return NULL; + + // Generally speaking this can be updated during the application life time + + ctx->link_info.max_payload = (cap[1] & 0x07) + 7; + ctx->link_info.payload = ((cap[2] >> 5) & 0x07) + 7; + ctx->link_info.link_speed = (cap[3]&0xF); + ctx->link_info.link_width = (cap[3]&0x3F0) >> 4; + ctx->link_info.max_link_speed = (cap[4]&0xF0000) >> 16; + ctx->link_info.max_link_width = (cap[4]&0x3F00000) >> 20; + + return &ctx->link_info; +} diff --git a/pcilib/pci.h b/pcilib/pci.h index a914e84..ce8d119 100644 --- a/pcilib/pci.h +++ b/pcilib/pci.h @@ -25,13 +25,24 @@ #include "model.h" #include "export.h" +typedef struct { + uint8_t max_link_speed, link_speed; + uint8_t max_link_width, link_width; + uint8_t max_payload, payload; +} pcilib_pcie_link_info_t; + struct pcilib_s { int handle; /**< file handle of device */ uintptr_t page_mask; /**< Selects bits which define offset within the page */ pcilib_board_info_t board_info; /**< The mandatory information about board as defined by PCI specification */ + pcilib_pcie_link_info_t link_info; /**< Infomation about PCIe connection */ char *bar_space[PCILIB_MAX_BARS]; /**< Pointers to the mapped BARs in virtual address space */ + int pci_cfg_space_fd; /**< File descriptor linking to PCI configuration space in sysfs */ + uint32_t pci_cfg_space_cache[64]; /**< Cached PCI configuration space */ + const uint32_t *pcie_capabilities; /**< PCI Capbility structure (just a pointer at appropriate place in the pci_cfg_space) */ + int reg_bar_mapped; /**< Indicates that all BARs used to access registers are mapped */ pcilib_bar_t reg_bar; /**< Default BAR to look for registers, other BARs will be looked as well */ int data_bar_mapped; /**< Indicates that a BAR for large PIO is mapped */ @@ -64,9 +75,9 @@ struct pcilib_s { #endif /* PCILIB_FILE_IO */ }; - pcilib_context_t *pcilib_get_implementation_context(pcilib_t *ctx); const pcilib_board_info_t *pcilib_get_board_info(pcilib_t *ctx); +const pcilib_pcie_link_info_t *pcilib_get_pcie_link_info(pcilib_t *ctx); int pcilib_map_register_space(pcilib_t *ctx); int pcilib_map_data_space(pcilib_t *ctx, uintptr_t addr); -- cgit v1.2.3