From b094ad3be564e7cc59cca4ff0256550d3a55dd3b Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Tue, 8 Sep 2009 17:42:57 -0700 Subject: [PATCH] ioat3: xor support ioat3.2 adds xor offload support for up to 8 sources. It can also perform an xor-zero-sum operation to validate whether all given sources sum to zero, without writing to a destination. Xor descriptors differ from memcpy in that one operation may require multiple descriptors depending on the number of sources. When the number of sources exceeds 5 an extended descriptor is needed. These descriptors need to be accounted for when updating the DMA_COUNT register. Signed-off-by: Dan Williams --- drivers/dma/ioat/dma_v2.c | 2 +- drivers/dma/ioat/dma_v2.h | 3 + drivers/dma/ioat/dma_v3.c | 218 ++++++++++++++++++++++++++++++++++- drivers/dma/ioat/registers.h | 2 + 4 files changed, 222 insertions(+), 3 deletions(-) diff --git a/drivers/dma/ioat/dma_v2.c b/drivers/dma/ioat/dma_v2.c index 80ce32de8d3..ee295d48ba2 100644 --- a/drivers/dma/ioat/dma_v2.c +++ b/drivers/dma/ioat/dma_v2.c @@ -48,7 +48,7 @@ module_param(ioat_ring_max_alloc_order, int, 0644); MODULE_PARM_DESC(ioat_ring_max_alloc_order, "ioat2+: upper limit for dynamic ring resizing (default: n=16)"); -static void __ioat2_issue_pending(struct ioat2_dma_chan *ioat) +void __ioat2_issue_pending(struct ioat2_dma_chan *ioat) { void * __iomem reg_base = ioat->base.reg_base; diff --git a/drivers/dma/ioat/dma_v2.h b/drivers/dma/ioat/dma_v2.h index fa030f8e1f2..e23027d3dcb 100644 --- a/drivers/dma/ioat/dma_v2.h +++ b/drivers/dma/ioat/dma_v2.h @@ -127,6 +127,7 @@ static inline u16 ioat2_xferlen_to_descs(struct ioat2_dma_chan *ioat, size_t len * @raw: hardware raw (un-typed) descriptor * @txd: the generic software descriptor for all engines * @len: total transaction length for unmap + * @result: asynchronous result of validate operations * @id: identifier for debug */ @@ -143,6 +144,7 @@ struct ioat_ring_ent { }; struct dma_async_tx_descriptor txd; size_t len; + enum sum_check_flags *result; #ifdef DEBUG int id; #endif @@ -180,5 +182,6 @@ enum dma_status ioat2_is_complete(struct dma_chan *c, dma_cookie_t cookie, dma_cookie_t *done, dma_cookie_t *used); void __ioat2_restart_chan(struct ioat2_dma_chan *ioat); bool reshape_ring(struct ioat2_dma_chan *ioat, int order); +void __ioat2_issue_pending(struct ioat2_dma_chan *ioat); extern struct kobj_type ioat2_ktype; #endif /* IOATDMA_V2_H */ diff --git a/drivers/dma/ioat/dma_v3.c b/drivers/dma/ioat/dma_v3.c index 0913d11e09e..957c205f91d 100644 --- a/drivers/dma/ioat/dma_v3.c +++ b/drivers/dma/ioat/dma_v3.c @@ -64,8 +64,33 @@ #include "dma.h" #include "dma_v2.h" +/* ioat hardware assumes at least two sources for raid operations */ +#define src_cnt_to_sw(x) ((x) + 2) +#define src_cnt_to_hw(x) ((x) - 2) + +/* provide a lookup table for setting the source address in the base or + * extended descriptor of an xor descriptor + */ +static const u8 xor_idx_to_desc __read_mostly = 0xd0; +static const u8 xor_idx_to_field[] __read_mostly = { 1, 4, 5, 6, 7, 0, 1, 2 }; + +static dma_addr_t xor_get_src(struct ioat_raw_descriptor *descs[2], int idx) +{ + struct ioat_raw_descriptor *raw = descs[xor_idx_to_desc >> idx & 1]; + + return raw->field[xor_idx_to_field[idx]]; +} + +static void xor_set_src(struct ioat_raw_descriptor *descs[2], + dma_addr_t addr, u32 offset, int idx) +{ + struct ioat_raw_descriptor *raw = descs[xor_idx_to_desc >> idx & 1]; + + raw->field[xor_idx_to_field[idx]] = addr + offset; +} + static void ioat3_dma_unmap(struct ioat2_dma_chan *ioat, - struct ioat_ring_ent *desc) + struct ioat_ring_ent *desc, int idx) { struct ioat_chan_common *chan = &ioat->base; struct pci_dev *pdev = chan->device->pdev; @@ -86,13 +111,71 @@ static void ioat3_dma_unmap(struct ioat2_dma_chan *ioat, PCI_DMA_FROMDEVICE, flags, 1); break; } + case IOAT_OP_XOR_VAL: + case IOAT_OP_XOR: { + struct ioat_xor_descriptor *xor = desc->xor; + struct ioat_ring_ent *ext; + struct ioat_xor_ext_descriptor *xor_ex = NULL; + int src_cnt = src_cnt_to_sw(xor->ctl_f.src_cnt); + struct ioat_raw_descriptor *descs[2]; + int i; + + if (src_cnt > 5) { + ext = ioat2_get_ring_ent(ioat, idx + 1); + xor_ex = ext->xor_ex; + } + + if (!(flags & DMA_COMPL_SKIP_SRC_UNMAP)) { + descs[0] = (struct ioat_raw_descriptor *) xor; + descs[1] = (struct ioat_raw_descriptor *) xor_ex; + for (i = 0; i < src_cnt; i++) { + dma_addr_t src = xor_get_src(descs, i); + + ioat_unmap(pdev, src - offset, len, + PCI_DMA_TODEVICE, flags, 0); + } + + /* dest is a source in xor validate operations */ + if (xor->ctl_f.op == IOAT_OP_XOR_VAL) { + ioat_unmap(pdev, xor->dst_addr - offset, len, + PCI_DMA_TODEVICE, flags, 1); + break; + } + } + + if (!(flags & DMA_COMPL_SKIP_DEST_UNMAP)) + ioat_unmap(pdev, xor->dst_addr - offset, len, + PCI_DMA_FROMDEVICE, flags, 1); + break; + } default: dev_err(&pdev->dev, "%s: unknown op type: %#x\n", __func__, desc->hw->ctl_f.op); } } +static bool desc_has_ext(struct ioat_ring_ent *desc) +{ + struct ioat_dma_descriptor *hw = desc->hw; + + if (hw->ctl_f.op == IOAT_OP_XOR || + hw->ctl_f.op == IOAT_OP_XOR_VAL) { + struct ioat_xor_descriptor *xor = desc->xor; + if (src_cnt_to_sw(xor->ctl_f.src_cnt) > 5) + return true; + } + + return false; +} + +/** + * __cleanup - reclaim used descriptors + * @ioat: channel (ring) to clean + * + * The difference from the dma_v2.c __cleanup() is that this routine + * handles extended descriptors and dma-unmapping raid operations. + */ static void __cleanup(struct ioat2_dma_chan *ioat, unsigned long phys_complete) { struct ioat_chan_common *chan = &ioat->base; @@ -114,7 +197,7 @@ static void __cleanup(struct ioat2_dma_chan *ioat, unsigned long phys_complete) tx = &desc->txd; if (tx->cookie) { chan->completed_cookie = tx->cookie; - ioat3_dma_unmap(ioat, desc); + ioat3_dma_unmap(ioat, desc, ioat->tail + i); tx->cookie = 0; if (tx->callback) { tx->callback(tx->callback_param); @@ -124,6 +207,12 @@ static void __cleanup(struct ioat2_dma_chan *ioat, unsigned long phys_complete) if (tx->phys == phys_complete) seen_current = true; + + /* skip extended descriptors */ + if (desc_has_ext(desc)) { + BUG_ON(i + 1 >= active); + i++; + } } ioat->tail += i; BUG_ON(!seen_current); /* no active descs have written a completion? */ @@ -309,6 +398,121 @@ ioat3_prep_memset_lock(struct dma_chan *c, dma_addr_t dest, int value, return &desc->txd; } +static struct dma_async_tx_descriptor * +__ioat3_prep_xor_lock(struct dma_chan *c, enum sum_check_flags *result, + dma_addr_t dest, dma_addr_t *src, unsigned int src_cnt, + size_t len, unsigned long flags) +{ + struct ioat2_dma_chan *ioat = to_ioat2_chan(c); + struct ioat_ring_ent *compl_desc; + struct ioat_ring_ent *desc; + struct ioat_ring_ent *ext; + size_t total_len = len; + struct ioat_xor_descriptor *xor; + struct ioat_xor_ext_descriptor *xor_ex = NULL; + struct ioat_dma_descriptor *hw; + u32 offset = 0; + int num_descs; + int with_ext; + int i; + u16 idx; + u8 op = result ? IOAT_OP_XOR_VAL : IOAT_OP_XOR; + + BUG_ON(src_cnt < 2); + + num_descs = ioat2_xferlen_to_descs(ioat, len); + /* we need 2x the number of descriptors to cover greater than 5 + * sources + */ + if (src_cnt > 5) { + with_ext = 1; + num_descs *= 2; + } else + with_ext = 0; + + /* completion writes from the raid engine may pass completion + * writes from the legacy engine, so we need one extra null + * (legacy) descriptor to ensure all completion writes arrive in + * order. + */ + if (likely(num_descs) && + ioat2_alloc_and_lock(&idx, ioat, num_descs+1) == 0) + /* pass */; + else + return NULL; + for (i = 0; i < num_descs; i += 1 + with_ext) { + struct ioat_raw_descriptor *descs[2]; + size_t xfer_size = min_t(size_t, len, 1 << ioat->xfercap_log); + int s; + + desc = ioat2_get_ring_ent(ioat, idx + i); + xor = desc->xor; + + /* save a branch by unconditionally retrieving the + * extended descriptor xor_set_src() knows to not write + * to it in the single descriptor case + */ + ext = ioat2_get_ring_ent(ioat, idx + i + 1); + xor_ex = ext->xor_ex; + + descs[0] = (struct ioat_raw_descriptor *) xor; + descs[1] = (struct ioat_raw_descriptor *) xor_ex; + for (s = 0; s < src_cnt; s++) + xor_set_src(descs, src[s], offset, s); + xor->size = xfer_size; + xor->dst_addr = dest + offset; + xor->ctl = 0; + xor->ctl_f.op = op; + xor->ctl_f.src_cnt = src_cnt_to_hw(src_cnt); + + len -= xfer_size; + offset += xfer_size; + dump_desc_dbg(ioat, desc); + } + + /* last xor descriptor carries the unmap parameters and fence bit */ + desc->txd.flags = flags; + desc->len = total_len; + if (result) + desc->result = result; + xor->ctl_f.fence = !!(flags & DMA_PREP_FENCE); + + /* completion descriptor carries interrupt bit */ + compl_desc = ioat2_get_ring_ent(ioat, idx + i); + compl_desc->txd.flags = flags & DMA_PREP_INTERRUPT; + hw = compl_desc->hw; + hw->ctl = 0; + hw->ctl_f.null = 1; + hw->ctl_f.int_en = !!(flags & DMA_PREP_INTERRUPT); + hw->ctl_f.compl_write = 1; + hw->size = NULL_DESC_BUFFER_SIZE; + dump_desc_dbg(ioat, compl_desc); + + /* we leave the channel locked to ensure in order submission */ + return &desc->txd; +} + +static struct dma_async_tx_descriptor * +ioat3_prep_xor(struct dma_chan *chan, dma_addr_t dest, dma_addr_t *src, + unsigned int src_cnt, size_t len, unsigned long flags) +{ + return __ioat3_prep_xor_lock(chan, NULL, dest, src, src_cnt, len, flags); +} + +struct dma_async_tx_descriptor * +ioat3_prep_xor_val(struct dma_chan *chan, dma_addr_t *src, + unsigned int src_cnt, size_t len, + enum sum_check_flags *result, unsigned long flags) +{ + /* the cleanup routine only sets bits on validate failure, it + * does not clear bits on validate success... so clear it here + */ + *result = 0; + + return __ioat3_prep_xor_lock(chan, result, src[0], &src[1], + src_cnt - 1, len, flags); +} + int __devinit ioat3_dma_probe(struct ioatdma_device *device, int dca) { struct pci_dev *pdev = device->pdev; @@ -333,6 +537,16 @@ int __devinit ioat3_dma_probe(struct ioatdma_device *device, int dca) dma_cap_set(DMA_MEMSET, dma->cap_mask); dma->device_prep_dma_memset = ioat3_prep_memset_lock; } + if (cap & IOAT_CAP_XOR) { + dma->max_xor = 8; + dma->xor_align = 2; + + dma_cap_set(DMA_XOR, dma->cap_mask); + dma->device_prep_dma_xor = ioat3_prep_xor; + + dma_cap_set(DMA_XOR_VAL, dma->cap_mask); + dma->device_prep_dma_xor_val = ioat3_prep_xor_val; + } /* -= IOAT ver.3 workarounds =- */ /* Write CHANERRMSK_INT with 3E07h to mask out the errors diff --git a/drivers/dma/ioat/registers.h b/drivers/dma/ioat/registers.h index 97d26ea6d72..63038e18ab0 100644 --- a/drivers/dma/ioat/registers.h +++ b/drivers/dma/ioat/registers.h @@ -243,6 +243,8 @@ #define IOAT_CHANERR_XOR_Q_ERR 0x20000 #define IOAT_CHANERR_DESCRIPTOR_COUNT_ERR 0x40000 +#define IOAT_CHANERR_HANDLE_MASK (IOAT_CHANERR_XOR_P_OR_CRC_ERR | IOAT_CHANERR_XOR_Q_ERR) + #define IOAT_CHANERR_MASK_OFFSET 0x2C /* 32-bit Channel Error Register */ #endif /* _IOAT_REGISTERS_H_ */ -- 2.39.3