From: Eli Cohen Date: Sun, 26 Feb 2006 22:36:06 +0000 (-0800) Subject: IB/mthca: Write FW commands through doorbell page X-Git-Tag: v2.6.17-rc1~1180^2~24 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=14abdffcc0a0ca9c5bb3274648d073e09a6fd2ba;p=linux-2.6 IB/mthca: Write FW commands through doorbell page This patch is checks whether the HCA supports posting FW commands through a doorbell page (user access region 0, or "UAR0"). If this is supported, the driver maps UAR0 and uses it for FW commands. This can be controlled by the value of a writable module parameter fw_cmd_doorbell. When the parameter is 0, the commands are posted through HCR using the old method; otherwise if HCA is capable commands go through UAR0. This use of UAR0 to post commands eliminates the need for polling the "go" bit prior to posting a new command. Since reading from a PCI device is much more expensive then issuing a posted write, it is expected that issuing FW commands this way will provide better CPU utilization. Signed-off-by: Eli Cohen Signed-off-by: Roland Dreier --- diff --git a/drivers/infiniband/hw/mthca/mthca_cmd.c b/drivers/infiniband/hw/mthca/mthca_cmd.c index 890c060ff4..d1e7ecb5f2 100644 --- a/drivers/infiniband/hw/mthca/mthca_cmd.c +++ b/drivers/infiniband/hw/mthca/mthca_cmd.c @@ -182,25 +182,58 @@ struct mthca_cmd_context { u8 status; }; +static int fw_cmd_doorbell = 1; +module_param(fw_cmd_doorbell, int, 0644); +MODULE_PARM_DESC(fw_cmd_doorbell, "post FW commands through doorbell page if nonzero " + "(and supported by FW)"); + static inline int go_bit(struct mthca_dev *dev) { return readl(dev->hcr + HCR_STATUS_OFFSET) & swab32(1 << HCR_GO_BIT); } -static int mthca_cmd_post(struct mthca_dev *dev, - u64 in_param, - u64 out_param, - u32 in_modifier, - u8 op_modifier, - u16 op, - u16 token, - int event) +static void mthca_cmd_post_dbell(struct mthca_dev *dev, + u64 in_param, + u64 out_param, + u32 in_modifier, + u8 op_modifier, + u16 op, + u16 token) { - int err = 0; + void __iomem *ptr = dev->cmd.dbell_map; + u16 *offs = dev->cmd.dbell_offsets; - mutex_lock(&dev->cmd.hcr_mutex); + __raw_writel((__force u32) cpu_to_be32(in_param >> 32), ptr + offs[0]); + wmb(); + __raw_writel((__force u32) cpu_to_be32(in_param & 0xfffffffful), ptr + offs[1]); + wmb(); + __raw_writel((__force u32) cpu_to_be32(in_modifier), ptr + offs[2]); + wmb(); + __raw_writel((__force u32) cpu_to_be32(out_param >> 32), ptr + offs[3]); + wmb(); + __raw_writel((__force u32) cpu_to_be32(out_param & 0xfffffffful), ptr + offs[4]); + wmb(); + __raw_writel((__force u32) cpu_to_be32(token << 16), ptr + offs[5]); + wmb(); + __raw_writel((__force u32) cpu_to_be32((1 << HCR_GO_BIT) | + (1 << HCA_E_BIT) | + (op_modifier << HCR_OPMOD_SHIFT) | + op), ptr + offs[6]); + wmb(); + __raw_writel((__force u32) 0, ptr + offs[7]); + wmb(); +} +static int mthca_cmd_post_hcr(struct mthca_dev *dev, + u64 in_param, + u64 out_param, + u32 in_modifier, + u8 op_modifier, + u16 op, + u16 token, + int event) +{ if (event) { unsigned long end = jiffies + GO_BIT_TIMEOUT; @@ -210,10 +243,8 @@ static int mthca_cmd_post(struct mthca_dev *dev, } } - if (go_bit(dev)) { - err = -EAGAIN; - goto out; - } + if (go_bit(dev)) + return -EAGAIN; /* * We use writel (instead of something like memcpy_toio) @@ -236,7 +267,29 @@ static int mthca_cmd_post(struct mthca_dev *dev, (op_modifier << HCR_OPMOD_SHIFT) | op), dev->hcr + 6 * 4); -out: + return 0; +} + +static int mthca_cmd_post(struct mthca_dev *dev, + u64 in_param, + u64 out_param, + u32 in_modifier, + u8 op_modifier, + u16 op, + u16 token, + int event) +{ + int err = 0; + + mutex_lock(&dev->cmd.hcr_mutex); + + if (event && dev->cmd.flags & MTHCA_CMD_POST_DOORBELLS && fw_cmd_doorbell) + mthca_cmd_post_dbell(dev, in_param, out_param, in_modifier, + op_modifier, op, token); + else + err = mthca_cmd_post_hcr(dev, in_param, out_param, in_modifier, + op_modifier, op, token, event); + mutex_unlock(&dev->cmd.hcr_mutex); return err; } @@ -386,7 +439,7 @@ static int mthca_cmd_box(struct mthca_dev *dev, unsigned long timeout, u8 *status) { - if (dev->cmd.use_events) + if (dev->cmd.flags & MTHCA_CMD_USE_EVENTS) return mthca_cmd_wait(dev, in_param, &out_param, 0, in_modifier, op_modifier, op, timeout, status); @@ -423,7 +476,7 @@ static int mthca_cmd_imm(struct mthca_dev *dev, unsigned long timeout, u8 *status) { - if (dev->cmd.use_events) + if (dev->cmd.flags & MTHCA_CMD_USE_EVENTS) return mthca_cmd_wait(dev, in_param, out_param, 1, in_modifier, op_modifier, op, timeout, status); @@ -437,7 +490,7 @@ int mthca_cmd_init(struct mthca_dev *dev) { mutex_init(&dev->cmd.hcr_mutex); sema_init(&dev->cmd.poll_sem, 1); - dev->cmd.use_events = 0; + dev->cmd.flags = 0; dev->hcr = ioremap(pci_resource_start(dev->pdev, 0) + MTHCA_HCR_BASE, MTHCA_HCR_SIZE); @@ -461,6 +514,8 @@ void mthca_cmd_cleanup(struct mthca_dev *dev) { pci_pool_destroy(dev->cmd.pool); iounmap(dev->hcr); + if (dev->cmd.flags & MTHCA_CMD_POST_DOORBELLS) + iounmap(dev->cmd.dbell_map); } /* @@ -498,7 +553,8 @@ int mthca_cmd_use_events(struct mthca_dev *dev) ; /* nothing */ --dev->cmd.token_mask; - dev->cmd.use_events = 1; + dev->cmd.flags |= MTHCA_CMD_USE_EVENTS; + down(&dev->cmd.poll_sem); return 0; @@ -511,7 +567,7 @@ void mthca_cmd_use_polling(struct mthca_dev *dev) { int i; - dev->cmd.use_events = 0; + dev->cmd.flags &= ~MTHCA_CMD_USE_EVENTS; for (i = 0; i < dev->cmd.max_cmds; ++i) down(&dev->cmd.event_sem); @@ -661,12 +717,41 @@ int mthca_RUN_FW(struct mthca_dev *dev, u8 *status) return mthca_cmd(dev, 0, 0, 0, CMD_RUN_FW, CMD_TIME_CLASS_A, status); } +static void mthca_setup_cmd_doorbells(struct mthca_dev *dev, u64 base) +{ + unsigned long addr; + u16 max_off = 0; + int i; + + for (i = 0; i < 8; ++i) + max_off = max(max_off, dev->cmd.dbell_offsets[i]); + + if ((base & PAGE_MASK) != ((base + max_off) & PAGE_MASK)) { + mthca_warn(dev, "Firmware doorbell region at 0x%016llx, " + "length 0x%x crosses a page boundary\n", + (unsigned long long) base, max_off); + return; + } + + addr = pci_resource_start(dev->pdev, 2) + + ((pci_resource_len(dev->pdev, 2) - 1) & base); + dev->cmd.dbell_map = ioremap(addr, max_off + sizeof(u32)); + if (!dev->cmd.dbell_map) + return; + + dev->cmd.flags |= MTHCA_CMD_POST_DOORBELLS; + mthca_dbg(dev, "Mapped doorbell page for posting FW commands\n"); +} + int mthca_QUERY_FW(struct mthca_dev *dev, u8 *status) { struct mthca_mailbox *mailbox; u32 *outbox; + u64 base; + u32 tmp; int err = 0; u8 lg; + int i; #define QUERY_FW_OUT_SIZE 0x100 #define QUERY_FW_VER_OFFSET 0x00 @@ -674,6 +759,10 @@ int mthca_QUERY_FW(struct mthca_dev *dev, u8 *status) #define QUERY_FW_ERR_START_OFFSET 0x30 #define QUERY_FW_ERR_SIZE_OFFSET 0x38 +#define QUERY_FW_CMD_DB_EN_OFFSET 0x10 +#define QUERY_FW_CMD_DB_OFFSET 0x50 +#define QUERY_FW_CMD_DB_BASE 0x60 + #define QUERY_FW_START_OFFSET 0x20 #define QUERY_FW_END_OFFSET 0x28 @@ -702,16 +791,29 @@ int mthca_QUERY_FW(struct mthca_dev *dev, u8 *status) ((dev->fw_ver & 0xffff0000ull) >> 16) | ((dev->fw_ver & 0x0000ffffull) << 16); + mthca_dbg(dev, "FW version %012llx, max commands %d\n", + (unsigned long long) dev->fw_ver, dev->cmd.max_cmds); + MTHCA_GET(lg, outbox, QUERY_FW_MAX_CMD_OFFSET); dev->cmd.max_cmds = 1 << lg; MTHCA_GET(dev->catas_err.addr, outbox, QUERY_FW_ERR_START_OFFSET); MTHCA_GET(dev->catas_err.size, outbox, QUERY_FW_ERR_SIZE_OFFSET); - mthca_dbg(dev, "FW version %012llx, max commands %d\n", - (unsigned long long) dev->fw_ver, dev->cmd.max_cmds); mthca_dbg(dev, "Catastrophic error buffer at 0x%llx, size 0x%x\n", (unsigned long long) dev->catas_err.addr, dev->catas_err.size); + MTHCA_GET(tmp, outbox, QUERY_FW_CMD_DB_EN_OFFSET); + if (tmp & 0x1) { + mthca_dbg(dev, "FW supports commands through doorbells\n"); + + MTHCA_GET(base, outbox, QUERY_FW_CMD_DB_BASE); + for (i = 0; i < MTHCA_CMD_NUM_DBELL_DWORDS; ++i) + MTHCA_GET(dev->cmd.dbell_offsets[i], outbox, + QUERY_FW_CMD_DB_OFFSET + (i << 1)); + + mthca_setup_cmd_doorbells(dev, base); + } + if (mthca_is_memfree(dev)) { MTHCA_GET(dev->fw.arbel.fw_pages, outbox, QUERY_FW_SIZE_OFFSET); MTHCA_GET(dev->fw.arbel.clr_int_base, outbox, QUERY_FW_CLR_INT_BASE_OFFSET); diff --git a/drivers/infiniband/hw/mthca/mthca_dev.h b/drivers/infiniband/hw/mthca/mthca_dev.h index 7f0dc221fa..b2aea80a68 100644 --- a/drivers/infiniband/hw/mthca/mthca_dev.h +++ b/drivers/infiniband/hw/mthca/mthca_dev.h @@ -110,9 +110,17 @@ enum { MTHCA_OPCODE_INVALID = 0xff }; +enum { + MTHCA_CMD_USE_EVENTS = 1 << 0, + MTHCA_CMD_POST_DOORBELLS = 1 << 1 +}; + +enum { + MTHCA_CMD_NUM_DBELL_DWORDS = 8 +}; + struct mthca_cmd { struct pci_pool *pool; - int use_events; struct mutex hcr_mutex; struct semaphore poll_sem; struct semaphore event_sem; @@ -121,6 +129,9 @@ struct mthca_cmd { int free_head; struct mthca_cmd_context *context; u16 token_mask; + u32 flags; + void __iomem *dbell_map; + u16 dbell_offsets[MTHCA_CMD_NUM_DBELL_DWORDS]; }; struct mthca_limits {