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authorLuca Boccassi <luca.boccassi@gmail.com>2017-11-08 14:15:11 +0000
committerLuca Boccassi <luca.boccassi@gmail.com>2017-11-08 14:45:54 +0000
commit055c52583a2794da8ba1e85a48cce3832372b12f (patch)
tree8ceb1cb78fbb46a0f341f8ee24feb3c6b5540013 /drivers/net/nfp/nfp_nspu.c
parentf239aed5e674965691846e8ce3f187dd47523689 (diff)
New upstream version 17.11-rc3
Change-Id: I6a5baa40612fe0c20f30b5fa773a6cbbac63a685 Signed-off-by: Luca Boccassi <luca.boccassi@gmail.com>
Diffstat (limited to 'drivers/net/nfp/nfp_nspu.c')
-rw-r--r--drivers/net/nfp/nfp_nspu.c623
1 files changed, 623 insertions, 0 deletions
diff --git a/drivers/net/nfp/nfp_nspu.c b/drivers/net/nfp/nfp_nspu.c
new file mode 100644
index 00000000..6ba940cb
--- /dev/null
+++ b/drivers/net/nfp/nfp_nspu.c
@@ -0,0 +1,623 @@
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/file.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+
+#include <rte_log.h>
+#include <rte_byteorder.h>
+
+#include "nfp_nfpu.h"
+
+#define CFG_EXP_BAR_ADDR_SZ 1
+#define CFG_EXP_BAR_MAP_TYPE 1
+
+#define EXP_BAR_TARGET_SHIFT 23
+#define EXP_BAR_LENGTH_SHIFT 27 /* 0=32, 1=64 bit increment */
+#define EXP_BAR_MAP_TYPE_SHIFT 29 /* Bulk BAR map */
+
+/* NFP target for NSP access */
+#define NFP_NSP_TARGET 7
+
+/* Expansion BARs for mapping PF vnic BARs */
+#define NFP_NET_PF_CFG_EXP_BAR 6
+#define NFP_NET_PF_HW_QUEUES_EXP_BAR 5
+
+/*
+ * This is an NFP internal address used for configuring properly an NFP
+ * expansion BAR.
+ */
+#define MEM_CMD_BASE_ADDR 0x8100000000
+
+/* NSP interface registers */
+#define NSP_BASE (MEM_CMD_BASE_ADDR + 0x22100)
+#define NSP_STATUS 0x00
+#define NSP_COMMAND 0x08
+#define NSP_BUFFER 0x10
+#define NSP_DEFAULT_BUF 0x18
+#define NSP_DEFAULT_BUF_CFG 0x20
+
+#define NSP_MAGIC 0xab10
+#define NSP_STATUS_MAGIC(x) (((x) >> 48) & 0xffff)
+#define NSP_STATUS_MAJOR(x) (int)(((x) >> 44) & 0xf)
+#define NSP_STATUS_MINOR(x) (int)(((x) >> 32) & 0xfff)
+
+/* NSP commands */
+#define NSP_CMD_RESET 1
+#define NSP_CMD_FW_LOAD 6
+#define NSP_CMD_READ_ETH_TABLE 7
+#define NSP_CMD_WRITE_ETH_TABLE 8
+#define NSP_CMD_GET_SYMBOL 14
+
+#define NSP_BUFFER_CFG_SIZE_MASK (0xff)
+
+#define NSP_REG_ADDR(d, off, reg) ((uint8_t *)(d)->mem_base + (off) + (reg))
+#define NSP_REG_VAL(p) (*(uint64_t *)(p))
+
+/*
+ * An NFP expansion BAR is configured for allowing access to a specific NFP
+ * target:
+ *
+ * IN:
+ * desc: struct with basic NSP addresses to work with
+ * expbar: NFP PF expansion BAR index to configure
+ * tgt: NFP target to configure access
+ * addr: NFP target address
+ *
+ * OUT:
+ * pcie_offset: NFP PCI BAR offset to work with
+ */
+static void
+nfp_nspu_mem_bar_cfg(nspu_desc_t *desc, int expbar, int tgt,
+ uint64_t addr, uint64_t *pcie_offset)
+{
+ uint64_t x, y, barsz;
+ uint32_t *expbar_ptr;
+
+ barsz = desc->barsz;
+
+ /*
+ * NFP CPP address to configure. This comes from NFP 6000
+ * datasheet document based on Bulk mapping.
+ */
+ x = (addr >> (barsz - 3)) << (21 - (40 - (barsz - 3)));
+ x |= CFG_EXP_BAR_MAP_TYPE << EXP_BAR_MAP_TYPE_SHIFT;
+ x |= CFG_EXP_BAR_ADDR_SZ << EXP_BAR_LENGTH_SHIFT;
+ x |= tgt << EXP_BAR_TARGET_SHIFT;
+
+ /* Getting expansion bar configuration register address */
+ expbar_ptr = (uint32_t *)desc->cfg_base;
+ /* Each physical PCI BAR has 8 NFP expansion BARs */
+ expbar_ptr += (desc->pcie_bar * 8) + expbar;
+
+ /* Writing to the expansion BAR register */
+ *expbar_ptr = (uint32_t)x;
+
+ /* Getting the pcie offset to work with from userspace */
+ y = addr & ((uint64_t)(1 << (barsz - 3)) - 1);
+ *pcie_offset = y;
+}
+
+/*
+ * Configuring an expansion bar for accessing NSP userspace interface. This
+ * function configures always the same expansion bar, which implies access to
+ * previously configured NFP target is lost.
+ */
+static void
+nspu_xlate(nspu_desc_t *desc, uint64_t addr, uint64_t *pcie_offset)
+{
+ nfp_nspu_mem_bar_cfg(desc, desc->exp_bar, NFP_NSP_TARGET, addr,
+ pcie_offset);
+}
+
+int
+nfp_nsp_get_abi_version(nspu_desc_t *desc, int *major, int *minor)
+{
+ uint64_t pcie_offset;
+ uint64_t nsp_reg;
+
+ nspu_xlate(desc, NSP_BASE, &pcie_offset);
+ nsp_reg = NSP_REG_VAL(NSP_REG_ADDR(desc, pcie_offset, NSP_STATUS));
+
+ if (NSP_STATUS_MAGIC(nsp_reg) != NSP_MAGIC)
+ return -1;
+
+ *major = NSP_STATUS_MAJOR(nsp_reg);
+ *minor = NSP_STATUS_MINOR(nsp_reg);
+
+ return 0;
+}
+
+int
+nfp_nspu_init(nspu_desc_t *desc, int nfp, int pcie_bar, size_t pcie_barsz,
+ int exp_bar, void *exp_bar_cfg_base, void *exp_bar_mmap)
+{
+ uint64_t offset, buffaddr;
+ uint64_t nsp_reg;
+
+ desc->nfp = nfp;
+ desc->pcie_bar = pcie_bar;
+ desc->exp_bar = exp_bar;
+ desc->barsz = pcie_barsz;
+ desc->windowsz = 1 << (desc->barsz - 3);
+ desc->cfg_base = exp_bar_cfg_base;
+ desc->mem_base = exp_bar_mmap;
+
+ nspu_xlate(desc, NSP_BASE, &offset);
+
+ /*
+ * Other NSPU clients can use other buffers. Let's tell NSPU we use the
+ * default buffer.
+ */
+ buffaddr = NSP_REG_VAL(NSP_REG_ADDR(desc, offset, NSP_DEFAULT_BUF));
+ NSP_REG_VAL(NSP_REG_ADDR(desc, offset, NSP_BUFFER)) = buffaddr;
+
+ /* NFP internal addresses are 40 bits. Clean all other bits here */
+ buffaddr = buffaddr & (((uint64_t)1 << 40) - 1);
+ desc->bufaddr = buffaddr;
+
+ /* Lets get information about the buffer */
+ nsp_reg = NSP_REG_VAL(NSP_REG_ADDR(desc, offset, NSP_DEFAULT_BUF_CFG));
+
+ /* Buffer size comes in MBs. Coversion to bytes */
+ desc->buf_size = ((size_t)nsp_reg & NSP_BUFFER_CFG_SIZE_MASK) << 20;
+
+ return 0;
+}
+
+#define NSPU_NFP_BUF(addr, base, off) \
+ (*(uint64_t *)((uint8_t *)(addr)->mem_base + ((base) | (off))))
+
+#define NSPU_HOST_BUF(base, off) (*(uint64_t *)((uint8_t *)(base) + (off)))
+
+static int
+nspu_buff_write(nspu_desc_t *desc, void *buffer, size_t size)
+{
+ uint64_t pcie_offset, pcie_window_base, pcie_window_offset;
+ uint64_t windowsz = desc->windowsz;
+ uint64_t buffaddr, j, i = 0;
+ int ret = 0;
+
+ if (size > desc->buf_size)
+ return -1;
+
+ buffaddr = desc->bufaddr;
+ windowsz = desc->windowsz;
+
+ while (i < size) {
+ /* Expansion bar reconfiguration per window size */
+ nspu_xlate(desc, buffaddr + i, &pcie_offset);
+ pcie_window_base = pcie_offset & (~(windowsz - 1));
+ pcie_window_offset = pcie_offset & (windowsz - 1);
+ for (j = pcie_window_offset; ((j < windowsz) && (i < size));
+ j += 8) {
+ NSPU_NFP_BUF(desc, pcie_window_base, j) =
+ NSPU_HOST_BUF(buffer, i);
+ i += 8;
+ }
+ }
+
+ return ret;
+}
+
+static int
+nspu_buff_read(nspu_desc_t *desc, void *buffer, size_t size)
+{
+ uint64_t pcie_offset, pcie_window_base, pcie_window_offset;
+ uint64_t windowsz, i = 0, j;
+ uint64_t buffaddr;
+ int ret = 0;
+
+ if (size > desc->buf_size)
+ return -1;
+
+ buffaddr = desc->bufaddr;
+ windowsz = desc->windowsz;
+
+ while (i < size) {
+ /* Expansion bar reconfiguration per window size */
+ nspu_xlate(desc, buffaddr + i, &pcie_offset);
+ pcie_window_base = pcie_offset & (~(windowsz - 1));
+ pcie_window_offset = pcie_offset & (windowsz - 1);
+ for (j = pcie_window_offset; ((j < windowsz) && (i < size));
+ j += 8) {
+ NSPU_HOST_BUF(buffer, i) =
+ NSPU_NFP_BUF(desc, pcie_window_base, j);
+ i += 8;
+ }
+ }
+
+ return ret;
+}
+
+static int
+nspu_command(nspu_desc_t *desc, uint16_t cmd, int read, int write,
+ void *buffer, size_t rsize, size_t wsize)
+{
+ uint64_t status, cmd_reg;
+ uint64_t offset;
+ int retry = 0;
+ int retries = 120;
+ int ret = 0;
+
+ /* Same expansion BAR is used for different things */
+ nspu_xlate(desc, NSP_BASE, &offset);
+
+ status = NSP_REG_VAL(NSP_REG_ADDR(desc, offset, NSP_STATUS));
+
+ while ((status & 0x1) && (retry < retries)) {
+ status = NSP_REG_VAL(NSP_REG_ADDR(desc, offset, NSP_STATUS));
+ retry++;
+ sleep(1);
+ }
+
+ if (retry == retries)
+ return -1;
+
+ if (write) {
+ ret = nspu_buff_write(desc, buffer, wsize);
+ if (ret)
+ return ret;
+
+ /* Expansion BAR changes when writing the buffer */
+ nspu_xlate(desc, NSP_BASE, &offset);
+ }
+
+ NSP_REG_VAL(NSP_REG_ADDR(desc, offset, NSP_COMMAND)) =
+ (uint64_t)wsize << 32 | (uint64_t)cmd << 16 | 1;
+
+ retry = 0;
+
+ cmd_reg = NSP_REG_VAL(NSP_REG_ADDR(desc, offset, NSP_COMMAND));
+ while ((cmd_reg & 0x1) && (retry < retries)) {
+ cmd_reg = NSP_REG_VAL(NSP_REG_ADDR(desc, offset, NSP_COMMAND));
+ retry++;
+ sleep(1);
+ }
+ if (retry == retries)
+ return -1;
+
+ retry = 0;
+ status = NSP_REG_VAL(NSP_REG_ADDR(desc, offset, NSP_STATUS));
+ while ((status & 0x1) && (retry < retries)) {
+ status = NSP_REG_VAL(NSP_REG_ADDR(desc, offset, NSP_STATUS));
+ retry++;
+ sleep(1);
+ }
+
+ if (retry == retries)
+ return -1;
+
+ ret = status & (0xff << 8);
+ if (ret)
+ return ret;
+
+ if (read) {
+ ret = nspu_buff_read(desc, buffer, rsize);
+ if (ret)
+ return ret;
+ }
+
+ return ret;
+}
+
+static int
+nfp_fw_reset(nspu_desc_t *nspu_desc)
+{
+ int res;
+
+ res = nspu_command(nspu_desc, NSP_CMD_RESET, 0, 0, 0, 0, 0);
+
+ if (res < 0)
+ RTE_LOG(INFO, PMD, "fw reset failed: error %d", res);
+
+ return res;
+}
+
+#define DEFAULT_FW_PATH "/lib/firmware/netronome"
+#define DEFAULT_FW_FILENAME "nic_dpdk_default.nffw"
+
+static int
+nfp_fw_upload(nspu_desc_t *nspu_desc)
+{
+ int fw_f;
+ char *fw_buf;
+ char filename[100];
+ struct stat file_stat;
+ off_t fsize, bytes;
+ ssize_t size;
+ int ret;
+
+ size = nspu_desc->buf_size;
+
+ sprintf(filename, "%s/%s", DEFAULT_FW_PATH, DEFAULT_FW_FILENAME);
+ fw_f = open(filename, O_RDONLY);
+ if (fw_f < 0) {
+ RTE_LOG(INFO, PMD, "Firmware file %s/%s not found.",
+ DEFAULT_FW_PATH, DEFAULT_FW_FILENAME);
+ return -ENOENT;
+ }
+
+ fstat(fw_f, &file_stat);
+
+ fsize = file_stat.st_size;
+ RTE_LOG(DEBUG, PMD, "Firmware file with size: %" PRIu64 "\n",
+ (uint64_t)fsize);
+
+ if (fsize > (off_t)size) {
+ RTE_LOG(INFO, PMD, "fw file too big: %" PRIu64
+ " bytes (%" PRIu64 " max)",
+ (uint64_t)fsize, (uint64_t)size);
+ return -EINVAL;
+ }
+
+ fw_buf = malloc((size_t)size);
+ if (!fw_buf) {
+ RTE_LOG(INFO, PMD, "malloc failed for fw buffer");
+ return -ENOMEM;
+ }
+ memset(fw_buf, 0, size);
+
+ bytes = read(fw_f, fw_buf, fsize);
+ if (bytes != fsize) {
+ RTE_LOG(INFO, PMD, "Reading fw to buffer failed.\n"
+ "Just %" PRIu64 " of %" PRIu64 " bytes read.",
+ (uint64_t)bytes, (uint64_t)fsize);
+ free(fw_buf);
+ return -EIO;
+ }
+
+ ret = nspu_command(nspu_desc, NSP_CMD_FW_LOAD, 0, 1, fw_buf, 0, bytes);
+
+ free(fw_buf);
+
+ return ret;
+}
+
+/* Firmware symbol descriptor size */
+#define NFP_SYM_DESC_LEN 40
+
+#define SYMBOL_DATA(b, off) (*(int64_t *)((b) + (off)))
+#define SYMBOL_UDATA(b, off) (*(uint64_t *)((b) + (off)))
+
+/* Firmware symbols contain information about how to access what they
+ * represent. It can be as simple as an numeric variable declared at a
+ * specific NFP memory, but it can also be more complex structures and
+ * related to specific hardware functionalities or components. Target,
+ * domain and address allow to create the BAR window for accessing such
+ * hw object and size defines the length to map.
+ *
+ * A vNIC is a network interface implemented inside the NFP and using a
+ * subset of device PCI BARs. Specific firmware symbols allow to map those
+ * vNIC bars by host drivers like the NFP PMD.
+ *
+ * Accessing what the symbol represents implies to map the access through
+ * a PCI BAR window. NFP expansion BARs are used in this regard through
+ * the NSPU interface.
+ */
+static int
+nfp_nspu_set_bar_from_symbl(nspu_desc_t *desc, const char *symbl,
+ uint32_t expbar, uint64_t *pcie_offset,
+ ssize_t *size)
+{
+ int64_t type;
+ int64_t target;
+ int64_t domain;
+ uint64_t addr;
+ char *sym_buf;
+ int ret = 0;
+
+ sym_buf = malloc(desc->buf_size);
+ strncpy(sym_buf, symbl, strlen(symbl));
+ ret = nspu_command(desc, NSP_CMD_GET_SYMBOL, 1, 1, sym_buf,
+ NFP_SYM_DESC_LEN, strlen(symbl));
+ if (ret) {
+ RTE_LOG(DEBUG, PMD, "symbol resolution (%s) failed\n", symbl);
+ goto clean;
+ }
+
+ /* Reading symbol information */
+ type = SYMBOL_DATA(sym_buf, 0);
+ target = SYMBOL_DATA(sym_buf, 8);
+ domain = SYMBOL_DATA(sym_buf, 16);
+ addr = SYMBOL_UDATA(sym_buf, 24);
+ *size = (ssize_t)SYMBOL_UDATA(sym_buf, 32);
+
+ if (type != 1) {
+ RTE_LOG(INFO, PMD, "wrong symbol type\n");
+ ret = -EINVAL;
+ goto clean;
+ }
+ if (!(target == 7 || target == -7)) {
+ RTE_LOG(INFO, PMD, "wrong symbol target\n");
+ ret = -EINVAL;
+ goto clean;
+ }
+ if (domain == 8 || domain == 9) {
+ RTE_LOG(INFO, PMD, "wrong symbol domain\n");
+ ret = -EINVAL;
+ goto clean;
+ }
+
+ /* Adjusting address based on symbol location */
+ if ((domain >= 24) && (domain < 28) && (target == 7)) {
+ addr = 1ULL << 37 | addr | ((uint64_t)domain & 0x3) << 35;
+ } else {
+ addr = 1ULL << 39 | addr | ((uint64_t)domain & 0x3f) << 32;
+ if (target == -7)
+ target = 7;
+ }
+
+ /* Configuring NFP expansion bar for mapping specific PCI BAR window */
+ nfp_nspu_mem_bar_cfg(desc, expbar, target, addr, pcie_offset);
+
+ /* This is the PCI BAR offset to use by the host */
+ *pcie_offset |= ((expbar & 0x7) << (desc->barsz - 3));
+
+clean:
+ free(sym_buf);
+ return ret;
+}
+
+int
+nfp_nsp_fw_setup(nspu_desc_t *desc, const char *sym, uint64_t *pcie_offset)
+{
+ ssize_t bar0_sym_size;
+
+ /* If the symbol resolution works, it implies a firmware app
+ * is already there.
+ */
+ if (!nfp_nspu_set_bar_from_symbl(desc, sym, NFP_NET_PF_CFG_EXP_BAR,
+ pcie_offset, &bar0_sym_size))
+ return 0;
+
+ /* No firmware app detected or not the right one */
+ RTE_LOG(INFO, PMD, "No firmware detected. Resetting NFP...\n");
+ if (nfp_fw_reset(desc) < 0) {
+ RTE_LOG(ERR, PMD, "nfp fw reset failed\n");
+ return -ENODEV;
+ }
+
+ RTE_LOG(INFO, PMD, "Reset done.\n");
+ RTE_LOG(INFO, PMD, "Uploading firmware...\n");
+
+ if (nfp_fw_upload(desc) < 0) {
+ RTE_LOG(ERR, PMD, "nfp fw upload failed\n");
+ return -ENODEV;
+ }
+
+ RTE_LOG(INFO, PMD, "Done.\n");
+
+ /* Now the symbol should be there */
+ if (nfp_nspu_set_bar_from_symbl(desc, sym, NFP_NET_PF_CFG_EXP_BAR,
+ pcie_offset, &bar0_sym_size)) {
+ RTE_LOG(ERR, PMD, "nfp PF BAR symbol resolution failed\n");
+ return -ENODEV;
+ }
+
+ return 0;
+}
+
+int
+nfp_nsp_map_ctrl_bar(nspu_desc_t *desc, uint64_t *pcie_offset)
+{
+ ssize_t bar0_sym_size;
+
+ if (nfp_nspu_set_bar_from_symbl(desc, "_pf0_net_bar0",
+ NFP_NET_PF_CFG_EXP_BAR,
+ pcie_offset, &bar0_sym_size))
+ return -ENODEV;
+
+ return 0;
+}
+
+/*
+ * This is a hardcoded fixed NFP internal CPP bus address for the hw queues unit
+ * inside the PCIE island.
+ */
+#define NFP_CPP_PCIE_QUEUES ((uint64_t)(1ULL << 39) | 0x80000 | \
+ ((uint64_t)0x4 & 0x3f) << 32)
+
+/* Configure a specific NFP expansion bar for accessing the vNIC rx/tx BARs */
+void
+nfp_nsp_map_queues_bar(nspu_desc_t *desc, uint64_t *pcie_offset)
+{
+ nfp_nspu_mem_bar_cfg(desc, NFP_NET_PF_HW_QUEUES_EXP_BAR, 0,
+ NFP_CPP_PCIE_QUEUES, pcie_offset);
+
+ /* This is the pcie offset to use by the host */
+ *pcie_offset |= ((NFP_NET_PF_HW_QUEUES_EXP_BAR & 0x7) << (27 - 3));
+}
+
+int
+nfp_nsp_eth_config(nspu_desc_t *desc, int port, int up)
+{
+ union eth_table_entry *entries, *entry;
+ int modified;
+ int ret, idx;
+ int i;
+
+ idx = port;
+
+ RTE_LOG(INFO, PMD, "Hw ethernet port %d configure...\n", port);
+ rte_spinlock_lock(&desc->nsp_lock);
+ entries = malloc(NSP_ETH_TABLE_SIZE);
+ if (!entries) {
+ rte_spinlock_unlock(&desc->nsp_lock);
+ return -ENOMEM;
+ }
+
+ ret = nspu_command(desc, NSP_CMD_READ_ETH_TABLE, 1, 0, entries,
+ NSP_ETH_TABLE_SIZE, 0);
+ if (ret) {
+ rte_spinlock_unlock(&desc->nsp_lock);
+ return ret;
+ }
+
+ entry = entries;
+
+ for (i = 0; i < NSP_ETH_MAX_COUNT; i++) {
+ /* ports in use do not appear sequentially in the table */
+ if (!(entry->port & NSP_ETH_PORT_LANES_MASK)) {
+ /* entry not in use */
+ entry++;
+ continue;
+ }
+ if (idx == 0)
+ break;
+ idx--;
+ entry++;
+ }
+
+ if (i == NSP_ETH_MAX_COUNT) {
+ rte_spinlock_unlock(&desc->nsp_lock);
+ return -EINVAL;
+ }
+
+ if (up && !(entry->state & NSP_ETH_STATE_CONFIGURED)) {
+ entry->control |= NSP_ETH_STATE_CONFIGURED;
+ modified = 1;
+ }
+
+ if (!up && (entry->state & NSP_ETH_STATE_CONFIGURED)) {
+ entry->control &= ~NSP_ETH_STATE_CONFIGURED;
+ modified = 1;
+ }
+
+ if (modified) {
+ ret = nspu_command(desc, NSP_CMD_WRITE_ETH_TABLE, 0, 1, entries,
+ 0, NSP_ETH_TABLE_SIZE);
+ if (!ret)
+ RTE_LOG(INFO, PMD,
+ "Hw ethernet port %d configure done\n", port);
+ else
+ RTE_LOG(INFO, PMD,
+ "Hw ethernet port %d configure failed\n", port);
+ }
+ rte_spinlock_unlock(&desc->nsp_lock);
+ return ret;
+}
+
+int
+nfp_nsp_eth_read_table(nspu_desc_t *desc, union eth_table_entry **table)
+{
+ int ret;
+
+ RTE_LOG(INFO, PMD, "Reading hw ethernet table...\n");
+ /* port 0 allocates the eth table and read it using NSPU */
+ *table = malloc(NSP_ETH_TABLE_SIZE);
+ if (!table)
+ return -ENOMEM;
+
+ ret = nspu_command(desc, NSP_CMD_READ_ETH_TABLE, 1, 0, *table,
+ NSP_ETH_TABLE_SIZE, 0);
+ if (ret)
+ return ret;
+
+ RTE_LOG(INFO, PMD, "Done\n");
+
+ return 0;
+}