diff options
Diffstat (limited to 'drivers/usb/host/xhci-mem.c')
-rw-r--r-- | drivers/usb/host/xhci-mem.c | 305 |
1 files changed, 304 insertions, 1 deletions
diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c index 0e383f9c380c..7cf15ca854be 100644 --- a/drivers/usb/host/xhci-mem.c +++ b/drivers/usb/host/xhci-mem.c @@ -21,18 +21,215 @@ */ #include <linux/usb.h> +#include <linux/pci.h> #include "xhci.h" +/* + * Allocates a generic ring segment from the ring pool, sets the dma address, + * initializes the segment to zero, and sets the private next pointer to NULL. + * + * Section 4.11.1.1: + * "All components of all Command and Transfer TRBs shall be initialized to '0'" + */ +static struct xhci_segment *xhci_segment_alloc(struct xhci_hcd *xhci, gfp_t flags) +{ + struct xhci_segment *seg; + dma_addr_t dma; + + seg = kzalloc(sizeof *seg, flags); + if (!seg) + return 0; + xhci_dbg(xhci, "Allocating priv segment structure at 0x%x\n", + (unsigned int) seg); + + seg->trbs = dma_pool_alloc(xhci->segment_pool, flags, &dma); + if (!seg->trbs) { + kfree(seg); + return 0; + } + xhci_dbg(xhci, "// Allocating segment at 0x%x (virtual) 0x%x (DMA)\n", + (unsigned int) seg->trbs, (u32) dma); + + memset(seg->trbs, 0, SEGMENT_SIZE); + seg->dma = dma; + seg->next = NULL; + + return seg; +} + +static void xhci_segment_free(struct xhci_hcd *xhci, struct xhci_segment *seg) +{ + if (!seg) + return; + if (seg->trbs) { + xhci_dbg(xhci, "Freeing DMA segment at 0x%x" + " (virtual) 0x%x (DMA)\n", + (unsigned int) seg->trbs, (u32) seg->dma); + dma_pool_free(xhci->segment_pool, seg->trbs, seg->dma); + seg->trbs = NULL; + } + xhci_dbg(xhci, "Freeing priv segment structure at 0x%x\n", + (unsigned int) seg); + kfree(seg); +} + +/* + * Make the prev segment point to the next segment. + * + * Change the last TRB in the prev segment to be a Link TRB which points to the + * DMA address of the next segment. The caller needs to set any Link TRB + * related flags, such as End TRB, Toggle Cycle, and no snoop. + */ +static void xhci_link_segments(struct xhci_hcd *xhci, struct xhci_segment *prev, + struct xhci_segment *next, bool link_trbs) +{ + u32 val; + + if (!prev || !next) + return; + prev->next = next; + if (link_trbs) { + prev->trbs[TRBS_PER_SEGMENT-1].link.segment_ptr[0] = next->dma; + + /* Set the last TRB in the segment to have a TRB type ID of Link TRB */ + val = prev->trbs[TRBS_PER_SEGMENT-1].link.control; + val &= ~TRB_TYPE_BITMASK; + val |= TRB_TYPE(TRB_LINK); + prev->trbs[TRBS_PER_SEGMENT-1].link.control = val; + } + xhci_dbg(xhci, "Linking segment 0x%x to segment 0x%x (DMA)\n", + prev->dma, next->dma); +} + +/* XXX: Do we need the hcd structure in all these functions? */ +static void xhci_ring_free(struct xhci_hcd *xhci, struct xhci_ring *ring) +{ + struct xhci_segment *seg; + struct xhci_segment *first_seg; + + if (!ring || !ring->first_seg) + return; + first_seg = ring->first_seg; + seg = first_seg->next; + xhci_dbg(xhci, "Freeing ring at 0x%x\n", (unsigned int) ring); + while (seg != first_seg) { + struct xhci_segment *next = seg->next; + xhci_segment_free(xhci, seg); + seg = next; + } + xhci_segment_free(xhci, first_seg); + ring->first_seg = NULL; + kfree(ring); +} + +/** + * Create a new ring with zero or more segments. + * + * Link each segment together into a ring. + * Set the end flag and the cycle toggle bit on the last segment. + * See section 4.9.1 and figures 15 and 16. + */ +static struct xhci_ring *xhci_ring_alloc(struct xhci_hcd *xhci, + unsigned int num_segs, bool link_trbs, gfp_t flags) +{ + struct xhci_ring *ring; + struct xhci_segment *prev; + + ring = kzalloc(sizeof *(ring), flags); + xhci_dbg(xhci, "Allocating ring at 0x%x\n", (unsigned int) ring); + if (!ring) + return 0; + + if (num_segs == 0) + return ring; + + ring->first_seg = xhci_segment_alloc(xhci, flags); + if (!ring->first_seg) + goto fail; + num_segs--; + + prev = ring->first_seg; + while (num_segs > 0) { + struct xhci_segment *next; + + next = xhci_segment_alloc(xhci, flags); + if (!next) + goto fail; + xhci_link_segments(xhci, prev, next, link_trbs); + + prev = next; + num_segs--; + } + xhci_link_segments(xhci, prev, ring->first_seg, link_trbs); + + if (link_trbs) { + /* See section 4.9.2.1 and 6.4.4.1 */ + prev->trbs[TRBS_PER_SEGMENT-1].link.control |= (LINK_TOGGLE); + xhci_dbg(xhci, "Wrote link toggle flag to" + " segment 0x%x (virtual), 0x%x (DMA)\n", + (unsigned int) prev, (u32) prev->dma); + } + /* The ring is empty, so the enqueue pointer == dequeue pointer */ + ring->enqueue = ring->first_seg->trbs; + ring->dequeue = ring->enqueue; + /* The ring is initialized to 0. The producer must write 1 to the cycle + * bit to handover ownership of the TRB, so PCS = 1. The consumer must + * compare CCS to the cycle bit to check ownership, so CCS = 1. + */ + ring->cycle_state = 1; + + return ring; + +fail: + xhci_ring_free(xhci, ring); + return 0; +} + void xhci_mem_cleanup(struct xhci_hcd *xhci) { + struct pci_dev *pdev = to_pci_dev(xhci_to_hcd(xhci)->self.controller); + int size; + + /* XXX: Free all the segments in the various rings */ + + /* Free the Event Ring Segment Table and the actual Event Ring */ + xhci_writel(xhci, 0, &xhci->ir_set->erst_size); + xhci_writel(xhci, 0, &xhci->ir_set->erst_base[1]); + xhci_writel(xhci, 0, &xhci->ir_set->erst_base[0]); + xhci_writel(xhci, 0, &xhci->ir_set->erst_dequeue[1]); + xhci_writel(xhci, 0, &xhci->ir_set->erst_dequeue[0]); + size = sizeof(struct xhci_erst_entry)*(xhci->erst.num_entries); + if (xhci->erst.entries) + pci_free_consistent(pdev, size, + xhci->erst.entries, xhci->erst.erst_dma_addr); + xhci->erst.entries = NULL; + xhci_dbg(xhci, "Freed ERST\n"); + if (xhci->event_ring) + xhci_ring_free(xhci, xhci->event_ring); + xhci->event_ring = NULL; + xhci_dbg(xhci, "Freed event ring\n"); + + xhci_writel(xhci, 0, &xhci->op_regs->cmd_ring[1]); + xhci_writel(xhci, 0, &xhci->op_regs->cmd_ring[0]); + if (xhci->cmd_ring) + xhci_ring_free(xhci, xhci->cmd_ring); + xhci->cmd_ring = NULL; + xhci_dbg(xhci, "Freed command ring\n"); + if (xhci->segment_pool) + dma_pool_destroy(xhci->segment_pool); + xhci->segment_pool = NULL; + xhci_dbg(xhci, "Freed segment pool\n"); xhci->page_size = 0; xhci->page_shift = 0; } int xhci_mem_init(struct xhci_hcd *xhci, gfp_t flags) { + dma_addr_t dma; + struct device *dev = xhci_to_hcd(xhci)->self.controller; unsigned int val, val2; + struct xhci_segment *seg; u32 page_size; int i; @@ -65,7 +262,113 @@ int xhci_mem_init(struct xhci_hcd *xhci, gfp_t flags) (unsigned int) val); xhci_writel(xhci, val, &xhci->op_regs->config_reg); - xhci->ir_set = &xhci->run_regs->ir_set[0]; + /* + * Initialize the ring segment pool. The ring must be a contiguous + * structure comprised of TRBs. The TRBs must be 16 byte aligned, + * however, the command ring segment needs 64-byte aligned segments, + * so we pick the greater alignment need. + */ + xhci->segment_pool = dma_pool_create("xHCI ring segments", dev, + SEGMENT_SIZE, 64, xhci->page_size); + if (!xhci->segment_pool) + goto fail; + + /* Set up the command ring to have one segments for now. */ + xhci->cmd_ring = xhci_ring_alloc(xhci, 1, true, flags); + if (!xhci->cmd_ring) + goto fail; + xhci_dbg(xhci, "Allocated command ring at 0x%x\n", (unsigned int) xhci->cmd_ring); + xhci_dbg(xhci, "First segment DMA is 0x%x\n", (unsigned int) xhci->cmd_ring->first_seg->dma); + + /* Set the address in the Command Ring Control register */ + val = xhci_readl(xhci, &xhci->op_regs->cmd_ring[0]); + val = (val & ~CMD_RING_ADDR_MASK) | + (xhci->cmd_ring->first_seg->dma & CMD_RING_ADDR_MASK) | + xhci->cmd_ring->cycle_state; + xhci_dbg(xhci, "// Setting command ring address high bits to 0x0\n"); + xhci_writel(xhci, (u32) 0, &xhci->op_regs->cmd_ring[1]); + xhci_dbg(xhci, "// Setting command ring address low bits to 0x%x\n", val); + xhci_writel(xhci, val, &xhci->op_regs->cmd_ring[0]); + xhci_dbg_cmd_ptrs(xhci); + + val = xhci_readl(xhci, &xhci->cap_regs->db_off); + val &= DBOFF_MASK; + xhci_dbg(xhci, "// Doorbell array is located at offset 0x%x" + " from cap regs base addr\n", val); + xhci->dba = (void *) xhci->cap_regs + val; + xhci_dbg_regs(xhci); + xhci_print_run_regs(xhci); + /* Set ir_set to interrupt register set 0 */ + xhci->ir_set = (void *) xhci->run_regs->ir_set; + + /* + * Event ring setup: Allocate a normal ring, but also setup + * the event ring segment table (ERST). Section 4.9.3. + */ + xhci_dbg(xhci, "// Allocating event ring\n"); + xhci->event_ring = xhci_ring_alloc(xhci, ERST_NUM_SEGS, false, flags); + if (!xhci->event_ring) + goto fail; + + xhci->erst.entries = pci_alloc_consistent(to_pci_dev(dev), + sizeof(struct xhci_erst_entry)*ERST_NUM_SEGS, &dma); + if (!xhci->erst.entries) + goto fail; + xhci_dbg(xhci, "// Allocated event ring segment table at 0x%x\n", dma); + + memset(xhci->erst.entries, 0, sizeof(struct xhci_erst_entry)*ERST_NUM_SEGS); + xhci->erst.num_entries = ERST_NUM_SEGS; + xhci->erst.erst_dma_addr = dma; + xhci_dbg(xhci, "Set ERST to 0; private num segs = %i, virt addr = 0x%x, dma addr = 0x%x\n", + xhci->erst.num_entries, + (unsigned int) xhci->erst.entries, + xhci->erst.erst_dma_addr); + + /* set ring base address and size for each segment table entry */ + for (val = 0, seg = xhci->event_ring->first_seg; val < ERST_NUM_SEGS; val++) { + struct xhci_erst_entry *entry = &xhci->erst.entries[val]; + entry->seg_addr[1] = 0; + entry->seg_addr[0] = seg->dma; + entry->seg_size = TRBS_PER_SEGMENT; + entry->rsvd = 0; + seg = seg->next; + } + + /* set ERST count with the number of entries in the segment table */ + val = xhci_readl(xhci, &xhci->ir_set->erst_size); + val &= ERST_SIZE_MASK; + val |= ERST_NUM_SEGS; + xhci_dbg(xhci, "// Write ERST size = %i to ir_set 0 (some bits preserved)\n", + val); + xhci_writel(xhci, val, &xhci->ir_set->erst_size); + + xhci_dbg(xhci, "// Set ERST entries to point to event ring.\n"); + /* set the segment table base address */ + xhci_dbg(xhci, "// Set ERST base address for ir_set 0 = 0x%x\n", + xhci->erst.erst_dma_addr); + xhci_writel(xhci, 0, &xhci->ir_set->erst_base[1]); + val = xhci_readl(xhci, &xhci->ir_set->erst_base[0]); + val &= ERST_PTR_MASK; + val |= (xhci->erst.erst_dma_addr & ~ERST_PTR_MASK); + xhci_writel(xhci, val, &xhci->ir_set->erst_base[0]); + + /* Set the event ring dequeue address */ + xhci_dbg(xhci, "// Set ERST dequeue address for ir_set 0 = 0x%x%x\n", + xhci->erst.entries[0].seg_addr[1], xhci->erst.entries[0].seg_addr[0]); + val = xhci_readl(xhci, &xhci->run_regs->ir_set[0].erst_dequeue[0]); + val &= ERST_PTR_MASK; + val |= (xhci->erst.entries[0].seg_addr[0] & ~ERST_PTR_MASK); + xhci_writel(xhci, val, &xhci->run_regs->ir_set[0].erst_dequeue[0]); + xhci_writel(xhci, xhci->erst.entries[0].seg_addr[1], + &xhci->run_regs->ir_set[0].erst_dequeue[1]); + xhci_dbg(xhci, "Wrote ERST address to ir_set 0.\n"); + xhci_print_ir_set(xhci, xhci->ir_set, 0); + + /* + * XXX: Might need to set the Interrupter Moderation Register to + * something other than the default (~1ms minimum between interrupts). + * See section 5.5.1.2. + */ return 0; fail: |