diff options
Diffstat (limited to 'drivers/gpu/drm/via/via_dmablit.c')
| -rw-r--r-- | drivers/gpu/drm/via/via_dmablit.c | 816 |
1 files changed, 816 insertions, 0 deletions
diff --git a/drivers/gpu/drm/via/via_dmablit.c b/drivers/gpu/drm/via/via_dmablit.c new file mode 100644 index 00000000000..409e00afdd0 --- /dev/null +++ b/drivers/gpu/drm/via/via_dmablit.c @@ -0,0 +1,816 @@ +/* via_dmablit.c -- PCI DMA BitBlt support for the VIA Unichrome/Pro + * + * Copyright (C) 2005 Thomas Hellstrom, All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sub license, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice (including the + * next paragraph) shall be included in all copies or substantial portions + * of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL + * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, + * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR + * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE + * USE OR OTHER DEALINGS IN THE SOFTWARE. + * + * Authors: + * Thomas Hellstrom. + * Partially based on code obtained from Digeo Inc. + */ + + +/* + * Unmaps the DMA mappings. + * FIXME: Is this a NoOp on x86? Also + * FIXME: What happens if this one is called and a pending blit has previously done + * the same DMA mappings? + */ + +#include "drmP.h" +#include "via_drm.h" +#include "via_drv.h" +#include "via_dmablit.h" + +#include <linux/pagemap.h> + +#define VIA_PGDN(x) (((unsigned long)(x)) & PAGE_MASK) +#define VIA_PGOFF(x) (((unsigned long)(x)) & ~PAGE_MASK) +#define VIA_PFN(x) ((unsigned long)(x) >> PAGE_SHIFT) + +typedef struct _drm_via_descriptor { + uint32_t mem_addr; + uint32_t dev_addr; + uint32_t size; + uint32_t next; +} drm_via_descriptor_t; + + +/* + * Unmap a DMA mapping. + */ + + + +static void +via_unmap_blit_from_device(struct pci_dev *pdev, drm_via_sg_info_t *vsg) +{ + int num_desc = vsg->num_desc; + unsigned cur_descriptor_page = num_desc / vsg->descriptors_per_page; + unsigned descriptor_this_page = num_desc % vsg->descriptors_per_page; + drm_via_descriptor_t *desc_ptr = vsg->desc_pages[cur_descriptor_page] + + descriptor_this_page; + dma_addr_t next = vsg->chain_start; + + while(num_desc--) { + if (descriptor_this_page-- == 0) { + cur_descriptor_page--; + descriptor_this_page = vsg->descriptors_per_page - 1; + desc_ptr = vsg->desc_pages[cur_descriptor_page] + + descriptor_this_page; + } + dma_unmap_single(&pdev->dev, next, sizeof(*desc_ptr), DMA_TO_DEVICE); + dma_unmap_page(&pdev->dev, desc_ptr->mem_addr, desc_ptr->size, vsg->direction); + next = (dma_addr_t) desc_ptr->next; + desc_ptr--; + } +} + +/* + * If mode = 0, count how many descriptors are needed. + * If mode = 1, Map the DMA pages for the device, put together and map also the descriptors. + * Descriptors are run in reverse order by the hardware because we are not allowed to update the + * 'next' field without syncing calls when the descriptor is already mapped. + */ + +static void +via_map_blit_for_device(struct pci_dev *pdev, + const drm_via_dmablit_t *xfer, + drm_via_sg_info_t *vsg, + int mode) +{ + unsigned cur_descriptor_page = 0; + unsigned num_descriptors_this_page = 0; + unsigned char *mem_addr = xfer->mem_addr; + unsigned char *cur_mem; + unsigned char *first_addr = (unsigned char *)VIA_PGDN(mem_addr); + uint32_t fb_addr = xfer->fb_addr; + uint32_t cur_fb; + unsigned long line_len; + unsigned remaining_len; + int num_desc = 0; + int cur_line; + dma_addr_t next = 0 | VIA_DMA_DPR_EC; + drm_via_descriptor_t *desc_ptr = NULL; + + if (mode == 1) + desc_ptr = vsg->desc_pages[cur_descriptor_page]; + + for (cur_line = 0; cur_line < xfer->num_lines; ++cur_line) { + + line_len = xfer->line_length; + cur_fb = fb_addr; + cur_mem = mem_addr; + + while (line_len > 0) { + + remaining_len = min(PAGE_SIZE-VIA_PGOFF(cur_mem), line_len); + line_len -= remaining_len; + + if (mode == 1) { + desc_ptr->mem_addr = + dma_map_page(&pdev->dev, + vsg->pages[VIA_PFN(cur_mem) - + VIA_PFN(first_addr)], + VIA_PGOFF(cur_mem), remaining_len, + vsg->direction); + desc_ptr->dev_addr = cur_fb; + + desc_ptr->size = remaining_len; + desc_ptr->next = (uint32_t) next; + next = dma_map_single(&pdev->dev, desc_ptr, sizeof(*desc_ptr), + DMA_TO_DEVICE); + desc_ptr++; + if (++num_descriptors_this_page >= vsg->descriptors_per_page) { + num_descriptors_this_page = 0; + desc_ptr = vsg->desc_pages[++cur_descriptor_page]; + } + } + + num_desc++; + cur_mem += remaining_len; + cur_fb += remaining_len; + } + + mem_addr += xfer->mem_stride; + fb_addr += xfer->fb_stride; + } + + if (mode == 1) { + vsg->chain_start = next; + vsg->state = dr_via_device_mapped; + } + vsg->num_desc = num_desc; +} + +/* + * Function that frees up all resources for a blit. It is usable even if the + * blit info has only been partially built as long as the status enum is consistent + * with the actual status of the used resources. + */ + + +static void +via_free_sg_info(struct pci_dev *pdev, drm_via_sg_info_t *vsg) +{ + struct page *page; + int i; + + switch(vsg->state) { + case dr_via_device_mapped: + via_unmap_blit_from_device(pdev, vsg); + case dr_via_desc_pages_alloc: + for (i=0; i<vsg->num_desc_pages; ++i) { + if (vsg->desc_pages[i] != NULL) + free_page((unsigned long)vsg->desc_pages[i]); + } + kfree(vsg->desc_pages); + case dr_via_pages_locked: + for (i=0; i<vsg->num_pages; ++i) { + if ( NULL != (page = vsg->pages[i])) { + if (! PageReserved(page) && (DMA_FROM_DEVICE == vsg->direction)) + SetPageDirty(page); + page_cache_release(page); + } + } + case dr_via_pages_alloc: + vfree(vsg->pages); + default: + vsg->state = dr_via_sg_init; + } + if (vsg->bounce_buffer) { + vfree(vsg->bounce_buffer); + vsg->bounce_buffer = NULL; + } + vsg->free_on_sequence = 0; +} + +/* + * Fire a blit engine. + */ + +static void +via_fire_dmablit(struct drm_device *dev, drm_via_sg_info_t *vsg, int engine) +{ + drm_via_private_t *dev_priv = (drm_via_private_t *)dev->dev_private; + + VIA_WRITE(VIA_PCI_DMA_MAR0 + engine*0x10, 0); + VIA_WRITE(VIA_PCI_DMA_DAR0 + engine*0x10, 0); + VIA_WRITE(VIA_PCI_DMA_CSR0 + engine*0x04, VIA_DMA_CSR_DD | VIA_DMA_CSR_TD | + VIA_DMA_CSR_DE); + VIA_WRITE(VIA_PCI_DMA_MR0 + engine*0x04, VIA_DMA_MR_CM | VIA_DMA_MR_TDIE); + VIA_WRITE(VIA_PCI_DMA_BCR0 + engine*0x10, 0); + VIA_WRITE(VIA_PCI_DMA_DPR0 + engine*0x10, vsg->chain_start); + DRM_WRITEMEMORYBARRIER(); + VIA_WRITE(VIA_PCI_DMA_CSR0 + engine*0x04, VIA_DMA_CSR_DE | VIA_DMA_CSR_TS); + VIA_READ(VIA_PCI_DMA_CSR0 + engine*0x04); +} + +/* + * Obtain a page pointer array and lock all pages into system memory. A segmentation violation will + * occur here if the calling user does not have access to the submitted address. + */ + +static int +via_lock_all_dma_pages(drm_via_sg_info_t *vsg, drm_via_dmablit_t *xfer) +{ + int ret; + unsigned long first_pfn = VIA_PFN(xfer->mem_addr); + vsg->num_pages = VIA_PFN(xfer->mem_addr + (xfer->num_lines * xfer->mem_stride -1)) - + first_pfn + 1; + + if (NULL == (vsg->pages = vmalloc(sizeof(struct page *) * vsg->num_pages))) + return -ENOMEM; + memset(vsg->pages, 0, sizeof(struct page *) * vsg->num_pages); + down_read(¤t->mm->mmap_sem); + ret = get_user_pages(current, current->mm, + (unsigned long)xfer->mem_addr, + vsg->num_pages, + (vsg->direction == DMA_FROM_DEVICE), + 0, vsg->pages, NULL); + + up_read(¤t->mm->mmap_sem); + if (ret != vsg->num_pages) { + if (ret < 0) + return ret; + vsg->state = dr_via_pages_locked; + return -EINVAL; + } + vsg->state = dr_via_pages_locked; + DRM_DEBUG("DMA pages locked\n"); + return 0; +} + +/* + * Allocate DMA capable memory for the blit descriptor chain, and an array that keeps track of the + * pages we allocate. We don't want to use kmalloc for the descriptor chain because it may be + * quite large for some blits, and pages don't need to be contingous. + */ + +static int +via_alloc_desc_pages(drm_via_sg_info_t *vsg) +{ + int i; + + vsg->descriptors_per_page = PAGE_SIZE / sizeof( drm_via_descriptor_t); + vsg->num_desc_pages = (vsg->num_desc + vsg->descriptors_per_page - 1) / + vsg->descriptors_per_page; + + if (NULL == (vsg->desc_pages = kcalloc(vsg->num_desc_pages, sizeof(void *), GFP_KERNEL))) + return -ENOMEM; + + vsg->state = dr_via_desc_pages_alloc; + for (i=0; i<vsg->num_desc_pages; ++i) { + if (NULL == (vsg->desc_pages[i] = + (drm_via_descriptor_t *) __get_free_page(GFP_KERNEL))) + return -ENOMEM; + } + DRM_DEBUG("Allocated %d pages for %d descriptors.\n", vsg->num_desc_pages, + vsg->num_desc); + return 0; +} + +static void +via_abort_dmablit(struct drm_device *dev, int engine) +{ + drm_via_private_t *dev_priv = (drm_via_private_t *)dev->dev_private; + + VIA_WRITE(VIA_PCI_DMA_CSR0 + engine*0x04, VIA_DMA_CSR_TA); +} + +static void +via_dmablit_engine_off(struct drm_device *dev, int engine) +{ + drm_via_private_t *dev_priv = (drm_via_private_t *)dev->dev_private; + + VIA_WRITE(VIA_PCI_DMA_CSR0 + engine*0x04, VIA_DMA_CSR_TD | VIA_DMA_CSR_DD); +} + + + +/* + * The dmablit part of the IRQ handler. Trying to do only reasonably fast things here. + * The rest, like unmapping and freeing memory for done blits is done in a separate workqueue + * task. Basically the task of the interrupt handler is to submit a new blit to the engine, while + * the workqueue task takes care of processing associated with the old blit. + */ + +void +via_dmablit_handler(struct drm_device *dev, int engine, int from_irq) +{ + drm_via_private_t *dev_priv = (drm_via_private_t *)dev->dev_private; + drm_via_blitq_t *blitq = dev_priv->blit_queues + engine; + int cur; + int done_transfer; + unsigned long irqsave=0; + uint32_t status = 0; + + DRM_DEBUG("DMA blit handler called. engine = %d, from_irq = %d, blitq = 0x%lx\n", + engine, from_irq, (unsigned long) blitq); + + if (from_irq) { + spin_lock(&blitq->blit_lock); + } else { + spin_lock_irqsave(&blitq->blit_lock, irqsave); + } + + done_transfer = blitq->is_active && + (( status = VIA_READ(VIA_PCI_DMA_CSR0 + engine*0x04)) & VIA_DMA_CSR_TD); + done_transfer = done_transfer || ( blitq->aborting && !(status & VIA_DMA_CSR_DE)); + + cur = blitq->cur; + if (done_transfer) { + + blitq->blits[cur]->aborted = blitq->aborting; + blitq->done_blit_handle++; + DRM_WAKEUP(blitq->blit_queue + cur); + + cur++; + if (cur >= VIA_NUM_BLIT_SLOTS) + cur = 0; + blitq->cur = cur; + + /* + * Clear transfer done flag. + */ + + VIA_WRITE(VIA_PCI_DMA_CSR0 + engine*0x04, VIA_DMA_CSR_TD); + + blitq->is_active = 0; + blitq->aborting = 0; + schedule_work(&blitq->wq); + + } else if (blitq->is_active && time_after_eq(jiffies, blitq->end)) { + + /* + * Abort transfer after one second. + */ + + via_abort_dmablit(dev, engine); + blitq->aborting = 1; + blitq->end = jiffies + DRM_HZ; + } + + if (!blitq->is_active) { + if (blitq->num_outstanding) { + via_fire_dmablit(dev, blitq->blits[cur], engine); + blitq->is_active = 1; + blitq->cur = cur; + blitq->num_outstanding--; + blitq->end = jiffies + DRM_HZ; + if (!timer_pending(&blitq->poll_timer)) + mod_timer(&blitq->poll_timer, jiffies + 1); + } else { + if (timer_pending(&blitq->poll_timer)) { + del_timer(&blitq->poll_timer); + } + via_dmablit_engine_off(dev, engine); + } + } + + if (from_irq) { + spin_unlock(&blitq->blit_lock); + } else { + spin_unlock_irqrestore(&blitq->blit_lock, irqsave); + } +} + + + +/* + * Check whether this blit is still active, performing necessary locking. + */ + +static int +via_dmablit_active(drm_via_blitq_t *blitq, int engine, uint32_t handle, wait_queue_head_t **queue) +{ + unsigned long irqsave; + uint32_t slot; + int active; + + spin_lock_irqsave(&blitq->blit_lock, irqsave); + + /* + * Allow for handle wraparounds. + */ + + active = ((blitq->done_blit_handle - handle) > (1 << 23)) && + ((blitq->cur_blit_handle - handle) <= (1 << 23)); + + if (queue && active) { + slot = handle - blitq->done_blit_handle + blitq->cur -1; + if (slot >= VIA_NUM_BLIT_SLOTS) { + slot -= VIA_NUM_BLIT_SLOTS; + } + *queue = blitq->blit_queue + slot; + } + + spin_unlock_irqrestore(&blitq->blit_lock, irqsave); + + return active; +} + +/* + * Sync. Wait for at least three seconds for the blit to be performed. + */ + +static int +via_dmablit_sync(struct drm_device *dev, uint32_t handle, int engine) +{ + + drm_via_private_t *dev_priv = (drm_via_private_t *)dev->dev_private; + drm_via_blitq_t *blitq = dev_priv->blit_queues + engine; + wait_queue_head_t *queue; + int ret = 0; + + if (via_dmablit_active(blitq, engine, handle, &queue)) { + DRM_WAIT_ON(ret, *queue, 3 * DRM_HZ, + !via_dmablit_active(blitq, engine, handle, NULL)); + } + DRM_DEBUG("DMA blit sync handle 0x%x engine %d returned %d\n", + handle, engine, ret); + + return ret; +} + + +/* + * A timer that regularly polls the blit engine in cases where we don't have interrupts: + * a) Broken hardware (typically those that don't have any video capture facility). + * b) Blit abort. The hardware doesn't send an interrupt when a blit is aborted. + * The timer and hardware IRQ's can and do work in parallel. If the hardware has + * irqs, it will shorten the latency somewhat. + */ + + + +static void +via_dmablit_timer(unsigned long data) +{ + drm_via_blitq_t *blitq = (drm_via_blitq_t *) data; + struct drm_device *dev = blitq->dev; + int engine = (int) + (blitq - ((drm_via_private_t *)dev->dev_private)->blit_queues); + + DRM_DEBUG("Polling timer called for engine %d, jiffies %lu\n", engine, + (unsigned long) jiffies); + + via_dmablit_handler(dev, engine, 0); + + if (!timer_pending(&blitq->poll_timer)) { + mod_timer(&blitq->poll_timer, jiffies + 1); + + /* + * Rerun handler to delete timer if engines are off, and + * to shorten abort latency. This is a little nasty. + */ + + via_dmablit_handler(dev, engine, 0); + + } +} + + + + +/* + * Workqueue task that frees data and mappings associated with a blit. + * Also wakes up waiting processes. Each of these tasks handles one + * blit engine only and may not be called on each interrupt. + */ + + +static void +via_dmablit_workqueue(struct work_struct *work) +{ + drm_via_blitq_t *blitq = container_of(work, drm_via_blitq_t, wq); + struct drm_device *dev = blitq->dev; + unsigned long irqsave; + drm_via_sg_info_t *cur_sg; + int cur_released; + + + DRM_DEBUG("Workqueue task called for blit engine %ld\n",(unsigned long) + (blitq - ((drm_via_private_t *)dev->dev_private)->blit_queues)); + + spin_lock_irqsave(&blitq->blit_lock, irqsave); + + while(blitq->serviced != blitq->cur) { + + cur_released = blitq->serviced++; + + DRM_DEBUG("Releasing blit slot %d\n", cur_released); + + if (blitq->serviced >= VIA_NUM_BLIT_SLOTS) + blitq->serviced = 0; + + cur_sg = blitq->blits[cur_released]; + blitq->num_free++; + + spin_unlock_irqrestore(&blitq->blit_lock, irqsave); + + DRM_WAKEUP(&blitq->busy_queue); + + via_free_sg_info(dev->pdev, cur_sg); + kfree(cur_sg); + + spin_lock_irqsave(&blitq->blit_lock, irqsave); + } + + spin_unlock_irqrestore(&blitq->blit_lock, irqsave); +} + + +/* + * Init all blit engines. Currently we use two, but some hardware have 4. + */ + + +void +via_init_dmablit(struct drm_device *dev) +{ + int i,j; + drm_via_private_t *dev_priv = (drm_via_private_t *)dev->dev_private; + drm_via_blitq_t *blitq; + + pci_set_master(dev->pdev); + + for (i=0; i< VIA_NUM_BLIT_ENGINES; ++i) { + blitq = dev_priv->blit_queues + i; + blitq->dev = dev; + blitq->cur_blit_handle = 0; + blitq->done_blit_handle = 0; + blitq->head = 0; + blitq->cur = 0; + blitq->serviced = 0; + blitq->num_free = VIA_NUM_BLIT_SLOTS - 1; + blitq->num_outstanding = 0; + blitq->is_active = 0; + blitq->aborting = 0; + spin_lock_init(&blitq->blit_lock); + for (j=0; j<VIA_NUM_BLIT_SLOTS; ++j) { + DRM_INIT_WAITQUEUE(blitq->blit_queue + j); + } + DRM_INIT_WAITQUEUE(&blitq->busy_queue); + INIT_WORK(&blitq->wq, via_dmablit_workqueue); + setup_timer(&blitq->poll_timer, via_dmablit_timer, + (unsigned long)blitq); + } +} + +/* + * Build all info and do all mappings required for a blit. + */ + + +static int +via_build_sg_info(struct drm_device *dev, drm_via_sg_info_t *vsg, drm_via_dmablit_t *xfer) +{ + int draw = xfer->to_fb; + int ret = 0; + + vsg->direction = (draw) ? DMA_TO_DEVICE : DMA_FROM_DEVICE; + vsg->bounce_buffer = NULL; + + vsg->state = dr_via_sg_init; + + if (xfer->num_lines <= 0 || xfer->line_length <= 0) { + DRM_ERROR("Zero size bitblt.\n"); + return -EINVAL; + } + + /* + * Below check is a driver limitation, not a hardware one. We + * don't want to lock unused pages, and don't want to incoporate the + * extra logic of avoiding them. Make sure there are no. + * (Not a big limitation anyway.) + */ + + if ((xfer->mem_stride - xfer->line_length) > 2*PAGE_SIZE) { + DRM_ERROR("Too large system memory stride. Stride: %d, " + "Length: %d\n", xfer->mem_stride, xfer->line_length); + return -EINVAL; + } + + if ((xfer->mem_stride == xfer->line_length) && + (xfer->fb_stride == xfer->line_length)) { + xfer->mem_stride *= xfer->num_lines; + xfer->line_length = xfer->mem_stride; + xfer->fb_stride = xfer->mem_stride; + xfer->num_lines = 1; + } + + /* + * Don't lock an arbitrary large number of pages, since that causes a + * DOS security hole. + */ + + if (xfer->num_lines > 2048 || (xfer->num_lines*xfer->mem_stride > (2048*2048*4))) { + DRM_ERROR("Too large PCI DMA bitblt.\n"); + return -EINVAL; + } + + /* + * we allow a negative fb stride to allow flipping of images in + * transfer. + */ + + if (xfer->mem_stride < xfer->line_length || + abs(xfer->fb_stride) < xfer->line_length) { + DRM_ERROR("Invalid frame-buffer / memory stride.\n"); + return -EINVAL; + } + + /* + * A hardware bug seems to be worked around if system memory addresses start on + * 16 byte boundaries. This seems a bit restrictive however. VIA is contacted + * about this. Meanwhile, impose the following restrictions: + */ + +#ifdef VIA_BUGFREE + if ((((unsigned long)xfer->mem_addr & 3) != ((unsigned long)xfer->fb_addr & 3)) || + ((xfer->num_lines > 1) && ((xfer->mem_stride & 3) != (xfer->fb_stride & 3)))) { + DRM_ERROR("Invalid DRM bitblt alignment.\n"); + return -EINVAL; + } +#else + if ((((unsigned long)xfer->mem_addr & 15) || + ((unsigned long)xfer->fb_addr & 3)) || + ((xfer->num_lines > 1) && + ((xfer->mem_stride & 15) || (xfer->fb_stride & 3)))) { + DRM_ERROR("Invalid DRM bitblt alignment.\n"); + return -EINVAL; + } +#endif + + if (0 != (ret = via_lock_all_dma_pages(vsg, xfer))) { + DRM_ERROR("Could not lock DMA pages.\n"); + via_free_sg_info(dev->pdev, vsg); + return ret; + } + + via_map_blit_for_device(dev->pdev, xfer, vsg, 0); + if (0 != (ret = via_alloc_desc_pages(vsg))) { + DRM_ERROR("Could not allocate DMA descriptor pages.\n"); + via_free_sg_info(dev->pdev, vsg); + return ret; + } + via_map_blit_for_device(dev->pdev, xfer, vsg, 1); + + return 0; +} + + +/* + * Reserve one free slot in the blit queue. Will wait for one second for one + * to become available. Otherwise -EBUSY is returned. + */ + +static int +via_dmablit_grab_slot(drm_via_blitq_t *blitq, int engine) +{ + int ret=0; + unsigned long irqsave; + + DRM_DEBUG("Num free is %d\n", blitq->num_free); + spin_lock_irqsave(&blitq->blit_lock, irqsave); + while(blitq->num_free == 0) { + spin_unlock_irqrestore(&blitq->blit_lock, irqsave); + + DRM_WAIT_ON(ret, blitq->busy_queue, DRM_HZ, blitq->num_free > 0); + if (ret) { + return (-EINTR == ret) ? -EAGAIN : ret; + } + + spin_lock_irqsave(&blitq->blit_lock, irqsave); + } + + blitq->num_free--; + spin_unlock_irqrestore(&blitq->blit_lock, irqsave); + + return 0; +} + +/* + * Hand back a free slot if we changed our mind. + */ + +static void +via_dmablit_release_slot(drm_via_blitq_t *blitq) +{ + unsigned long irqsave; + + spin_lock_irqsave(&blitq->blit_lock, irqsave); + blitq->num_free++; + spin_unlock_irqrestore(&blitq->blit_lock, irqsave); + DRM_WAKEUP( &blitq->busy_queue ); +} + +/* + * Grab a free slot. Build blit info and queue a blit. + */ + + +static int +via_dmablit(struct drm_device *dev, drm_via_dmablit_t *xfer) +{ + drm_via_private_t *dev_priv = (drm_via_private_t *)dev->dev_private; + drm_via_sg_info_t *vsg; + drm_via_blitq_t *blitq; + int ret; + int engine; + unsigned long irqsave; + + if (dev_priv == NULL) { + DRM_ERROR("Called without initialization.\n"); + return -EINVAL; + } + + engine = (xfer->to_fb) ? 0 : 1; + blitq = dev_priv->blit_queues + engine; + if (0 != (ret = via_dmablit_grab_slot(blitq, engine))) { + return ret; + } + if (NULL == (vsg = kmalloc(sizeof(*vsg), GFP_KERNEL))) { + via_dmablit_release_slot(blitq); + return -ENOMEM; + } + if (0 != (ret = via_build_sg_info(dev, vsg, xfer))) { + via_dmablit_release_slot(blitq); + kfree(vsg); + return ret; + } + spin_lock_irqsave(&blitq->blit_lock, irqsave); + + blitq->blits[blitq->head++] = vsg; + if (blitq->head >= VIA_NUM_BLIT_SLOTS) + blitq->head = 0; + blitq->num_outstanding++; + xfer->sync.sync_handle = ++blitq->cur_blit_handle; + + spin_unlock_irqrestore(&blitq->blit_lock, irqsave); + xfer->sync.engine = engine; + + via_dmablit_handler(dev, engine, 0); + + return 0; +} + +/* + * Sync on a previously submitted blit. Note that the X server use signals extensively, and + * that there is a very big probability that this IOCTL will be interrupted by a signal. In that + * case it returns with -EAGAIN for the signal to be delivered. + * The caller should then reissue the IOCTL. This is similar to what is being done for drmGetLock(). + */ + +int +via_dma_blit_sync( struct drm_device *dev, void *data, struct drm_file *file_priv ) +{ + drm_via_blitsync_t *sync = data; + int err; + + if (sync->engine >= VIA_NUM_BLIT_ENGINES) + return -EINVAL; + + err = via_dmablit_sync(dev, sync->sync_handle, sync->engine); + + if (-EINTR == err) + err = -EAGAIN; + + return err; +} + + +/* + * Queue a blit and hand back a handle to be used for sync. This IOCTL may be interrupted by a signal + * while waiting for a free slot in the blit queue. In that case it returns with -EAGAIN and should + * be reissued. See the above IOCTL code. + */ + +int +via_dma_blit( struct drm_device *dev, void *data, struct drm_file *file_priv ) +{ + drm_via_dmablit_t *xfer = data; + int err; + + err = via_dmablit(dev, xfer); + + return err; +} |