/* r128_cce.c -- ATI Rage 128 driver -*- linux-c -*-
 * Created: Wed Apr  5 19:24:19 2000 by kevin@precisioninsight.com
 */
/*
 * Copyright 2000 Precision Insight, Inc., Cedar Park, Texas.
 * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
 * 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, sublicense,
 * 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 NONINFRINGEMENT.  IN NO EVENT SHALL
 * PRECISION INSIGHT 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:
 *    Gareth Hughes <gareth@valinux.com>
 */

#include <linux/delay.h>
#include <linux/dma-mapping.h>
#include <linux/firmware.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/uaccess.h>

#include <drm/drm_device.h>
#include <drm/drm_file.h>
#include <drm/drm_legacy.h>
#include <drm/drm_print.h>
#include <drm/r128_drm.h>

#include "r128_drv.h"

#define R128_FIFO_DEBUG         0

#define FIRMWARE_NAME           "r128/r128_cce.bin"

MODULE_FIRMWARE(FIRMWARE_NAME);

static int R128_READ_PLL(struct drm_device *dev, int addr)
{
        drm_r128_private_t *dev_priv = dev->dev_private;

        R128_WRITE8(R128_CLOCK_CNTL_INDEX, addr & 0x1f);
        return R128_READ(R128_CLOCK_CNTL_DATA);
}

#if R128_FIFO_DEBUG
static void r128_status(drm_r128_private_t *dev_priv)
{
        printk("GUI_STAT           = 0x%08x\n",
               (unsigned int)R128_READ(R128_GUI_STAT));
        printk("PM4_STAT           = 0x%08x\n",
               (unsigned int)R128_READ(R128_PM4_STAT));
        printk("PM4_BUFFER_DL_WPTR = 0x%08x\n",
               (unsigned int)R128_READ(R128_PM4_BUFFER_DL_WPTR));
        printk("PM4_BUFFER_DL_RPTR = 0x%08x\n",
               (unsigned int)R128_READ(R128_PM4_BUFFER_DL_RPTR));
        printk("PM4_MICRO_CNTL     = 0x%08x\n",
               (unsigned int)R128_READ(R128_PM4_MICRO_CNTL));
        printk("PM4_BUFFER_CNTL    = 0x%08x\n",
               (unsigned int)R128_READ(R128_PM4_BUFFER_CNTL));
}
#endif

/* ================================================================
 * Engine, FIFO control
 */

static int r128_do_pixcache_flush(drm_r128_private_t *dev_priv)
{
        u32 tmp;
        int i;

        tmp = R128_READ(R128_PC_NGUI_CTLSTAT) | R128_PC_FLUSH_ALL;
        R128_WRITE(R128_PC_NGUI_CTLSTAT, tmp);

        for (i = 0; i < dev_priv->usec_timeout; i++) {
                if (!(R128_READ(R128_PC_NGUI_CTLSTAT) & R128_PC_BUSY))
                        return 0;
                udelay(1);
        }

#if R128_FIFO_DEBUG
        DRM_ERROR("failed!\n");
#endif
        return -EBUSY;
}

static int r128_do_wait_for_fifo(drm_r128_private_t *dev_priv, int entries)
{
        int i;

        for (i = 0; i < dev_priv->usec_timeout; i++) {
                int slots = R128_READ(R128_GUI_STAT) & R128_GUI_FIFOCNT_MASK;
                if (slots >= entries)
                        return 0;
                udelay(1);
        }

#if R128_FIFO_DEBUG
        DRM_ERROR("failed!\n");
#endif
        return -EBUSY;
}

static int r128_do_wait_for_idle(drm_r128_private_t *dev_priv)
{
        int i, ret;

        ret = r128_do_wait_for_fifo(dev_priv, 64);
        if (ret)
                return ret;

        for (i = 0; i < dev_priv->usec_timeout; i++) {
                if (!(R128_READ(R128_GUI_STAT) & R128_GUI_ACTIVE)) {
                        r128_do_pixcache_flush(dev_priv);
                        return 0;
                }
                udelay(1);
        }

#if R128_FIFO_DEBUG
        DRM_ERROR("failed!\n");
#endif
        return -EBUSY;
}

/* ================================================================
 * CCE control, initialization
 */

/* Load the microcode for the CCE */
static int r128_cce_load_microcode(drm_r128_private_t *dev_priv)
{
        struct platform_device *pdev;
        const struct firmware *fw;
        const __be32 *fw_data;
        int rc, i;

        DRM_DEBUG("\n");

        pdev = platform_device_register_simple("r128_cce", 0, NULL, 0);
        if (IS_ERR(pdev)) {
                pr_err("r128_cce: Failed to register firmware\n");
                return PTR_ERR(pdev);
        }
        rc = request_firmware(&fw, FIRMWARE_NAME, &pdev->dev);
        platform_device_unregister(pdev);
        if (rc) {
                pr_err("r128_cce: Failed to load firmware \"%s\"\n",
                       FIRMWARE_NAME);
                return rc;
        }

        if (fw->size != 256 * 8) {
                pr_err("r128_cce: Bogus length %zu in firmware \"%s\"\n",
                       fw->size, FIRMWARE_NAME);
                rc = -EINVAL;
                goto out_release;
        }

        r128_do_wait_for_idle(dev_priv);

        fw_data = (const __be32 *)fw->data;
        R128_WRITE(R128_PM4_MICROCODE_ADDR, 0);
        for (i = 0; i < 256; i++) {
                R128_WRITE(R128_PM4_MICROCODE_DATAH,
                           be32_to_cpup(&fw_data[i * 2]));
                R128_WRITE(R128_PM4_MICROCODE_DATAL,
                           be32_to_cpup(&fw_data[i * 2 + 1]));
        }

out_release:
        release_firmware(fw);
        return rc;
}

/* Flush any pending commands to the CCE.  This should only be used just
 * prior to a wait for idle, as it informs the engine that the command
 * stream is ending.
 */
static void r128_do_cce_flush(drm_r128_private_t *dev_priv)
{
        u32 tmp;

        tmp = R128_READ(R128_PM4_BUFFER_DL_WPTR) | R128_PM4_BUFFER_DL_DONE;
        R128_WRITE(R128_PM4_BUFFER_DL_WPTR, tmp);
}

/* Wait for the CCE to go idle.
 */
int r128_do_cce_idle(drm_r128_private_t *dev_priv)
{
        int i;

        for (i = 0; i < dev_priv->usec_timeout; i++) {
                if (GET_RING_HEAD(dev_priv) == dev_priv->ring.tail) {
                        int pm4stat = R128_READ(R128_PM4_STAT);
                        if (((pm4stat & R128_PM4_FIFOCNT_MASK) >=
                             dev_priv->cce_fifo_size) &&
                            !(pm4stat & (R128_PM4_BUSY |
                                         R128_PM4_GUI_ACTIVE))) {
                                return r128_do_pixcache_flush(dev_priv);
                        }
                }
                udelay(1);
        }

#if R128_FIFO_DEBUG
        DRM_ERROR("failed!\n");
        r128_status(dev_priv);
#endif
        return -EBUSY;
}

/* Start the Concurrent Command Engine.
 */
static void r128_do_cce_start(drm_r128_private_t *dev_priv)
{
        r128_do_wait_for_idle(dev_priv);

        R128_WRITE(R128_PM4_BUFFER_CNTL,
                   dev_priv->cce_mode | dev_priv->ring.size_l2qw
                   | R128_PM4_BUFFER_CNTL_NOUPDATE);
        R128_READ(R128_PM4_BUFFER_ADDR);        /* as per the sample code */
        R128_WRITE(R128_PM4_MICRO_CNTL, R128_PM4_MICRO_FREERUN);

        dev_priv->cce_running = 1;
}

/* Reset the Concurrent Command Engine.  This will not flush any pending
 * commands, so you must wait for the CCE command stream to complete
 * before calling this routine.
 */
static void r128_do_cce_reset(drm_r128_private_t *dev_priv)
{
        R128_WRITE(R128_PM4_BUFFER_DL_WPTR, 0);
        R128_WRITE(R128_PM4_BUFFER_DL_RPTR, 0);
        dev_priv->ring.tail = 0;
}

/* Stop the Concurrent Command Engine.  This will not flush any pending
 * commands, so you must flush the command stream and wait for the CCE
 * to go idle before calling this routine.
 */
static void r128_do_cce_stop(drm_r128_private_t *dev_priv)
{
        R128_WRITE(R128_PM4_MICRO_CNTL, 0);
        R128_WRITE(R128_PM4_BUFFER_CNTL,
                   R128_PM4_NONPM4 | R128_PM4_BUFFER_CNTL_NOUPDATE);

        dev_priv->cce_running = 0;
}

/* Reset the engine.  This will stop the CCE if it is running.
 */
static int r128_do_engine_reset(struct drm_device *dev)
{
        drm_r128_private_t *dev_priv = dev->dev_private;
        u32 clock_cntl_index, mclk_cntl, gen_reset_cntl;

        r128_do_pixcache_flush(dev_priv);

        clock_cntl_index = R128_READ(R128_CLOCK_CNTL_INDEX);
        mclk_cntl = R128_READ_PLL(dev, R128_MCLK_CNTL);

        R128_WRITE_PLL(R128_MCLK_CNTL,
                       mclk_cntl | R128_FORCE_GCP | R128_FORCE_PIPE3D_CP);

        gen_reset_cntl = R128_READ(R128_GEN_RESET_CNTL);

        /* Taken from the sample code - do not change */
        R128_WRITE(R128_GEN_RESET_CNTL, gen_reset_cntl | R128_SOFT_RESET_GUI);
        R128_READ(R128_GEN_RESET_CNTL);
        R128_WRITE(R128_GEN_RESET_CNTL, gen_reset_cntl & ~R128_SOFT_RESET_GUI);
        R128_READ(R128_GEN_RESET_CNTL);

        R128_WRITE_PLL(R128_MCLK_CNTL, mclk_cntl);
        R128_WRITE(R128_CLOCK_CNTL_INDEX, clock_cntl_index);
        R128_WRITE(R128_GEN_RESET_CNTL, gen_reset_cntl);

        /* Reset the CCE ring */
        r128_do_cce_reset(dev_priv);

        /* The CCE is no longer running after an engine reset */
        dev_priv->cce_running = 0;

        /* Reset any pending vertex, indirect buffers */
        r128_freelist_reset(dev);

        return 0;
}

static void r128_cce_init_ring_buffer(struct drm_device *dev,
                                      drm_r128_private_t *dev_priv)
{
        u32 ring_start;
        u32 tmp;

        DRM_DEBUG("\n");

        /* The manual (p. 2) says this address is in "VM space".  This
         * means it's an offset from the start of AGP space.
         */
#if IS_ENABLED(CONFIG_AGP)
        if (!dev_priv->is_pci)
                ring_start = dev_priv->cce_ring->offset - dev->agp->base;
        else
#endif
                ring_start = dev_priv->cce_ring->offset -
                    (unsigned long)dev->sg->virtual;

        R128_WRITE(R128_PM4_BUFFER_OFFSET, ring_start | R128_AGP_OFFSET);

        R128_WRITE(R128_PM4_BUFFER_DL_WPTR, 0);
        R128_WRITE(R128_PM4_BUFFER_DL_RPTR, 0);

        /* Set watermark control */
        R128_WRITE(R128_PM4_BUFFER_WM_CNTL,
                   ((R128_WATERMARK_L / 4) << R128_WMA_SHIFT)
                   | ((R128_WATERMARK_M / 4) << R128_WMB_SHIFT)
                   | ((R128_WATERMARK_N / 4) << R128_WMC_SHIFT)
                   | ((R128_WATERMARK_K / 64) << R128_WB_WM_SHIFT));

        /* Force read.  Why?  Because it's in the examples... */
        R128_READ(R128_PM4_BUFFER_ADDR);

        /* Turn on bus mastering */
        tmp = R128_READ(R128_BUS_CNTL) & ~R128_BUS_MASTER_DIS;
        R128_WRITE(R128_BUS_CNTL, tmp);
}

static int r128_do_init_cce(struct drm_device *dev, drm_r128_init_t *init)
{
        drm_r128_private_t *dev_priv;
        int rc;

        DRM_DEBUG("\n");

        if (dev->dev_private) {
                DRM_DEBUG("called when already initialized\n");
                return -EINVAL;
        }

        dev_priv = kzalloc(sizeof(drm_r128_private_t), GFP_KERNEL);
        if (dev_priv == NULL)
                return -ENOMEM;

        dev_priv->is_pci = init->is_pci;

        if (dev_priv->is_pci && !dev->sg) {
                DRM_ERROR("PCI GART memory not allocated!\n");
                dev->dev_private = (void *)dev_priv;
                r128_do_cleanup_cce(dev);
                return -EINVAL;
        }

        dev_priv->usec_timeout = init->usec_timeout;
        if (dev_priv->usec_timeout < 1 ||
            dev_priv->usec_timeout > R128_MAX_USEC_TIMEOUT) {
                DRM_DEBUG("TIMEOUT problem!\n");
                dev->dev_private = (void *)dev_priv;
                r128_do_cleanup_cce(dev);
                return -EINVAL;
        }

        dev_priv->cce_mode = init->cce_mode;

        /* GH: Simple idle check.
         */
        atomic_set(&dev_priv->idle_count, 0);

        /* We don't support anything other than bus-mastering ring mode,
         * but the ring can be in either AGP or PCI space for the ring
         * read pointer.
         */
        if ((init->cce_mode != R128_PM4_192BM) &&
            (init->cce_mode != R128_PM4_128BM_64INDBM) &&
            (init->cce_mode != R128_PM4_64BM_128INDBM) &&
            (init->cce_mode != R128_PM4_64BM_64VCBM_64INDBM)) {
                DRM_DEBUG("Bad cce_mode!\n");
                dev->dev_private = (void *)dev_priv;
                r128_do_cleanup_cce(dev);
                return -EINVAL;
        }

        switch (init->cce_mode) {
        case R128_PM4_NONPM4:
                dev_priv->cce_fifo_size = 0;
                break;
        case R128_PM4_192PIO:
        case R128_PM4_192BM:
                dev_priv->cce_fifo_size = 192;
                break;
        case R128_PM4_128PIO_64INDBM:
        case R128_PM4_128BM_64INDBM:
                dev_priv->cce_fifo_size = 128;
                break;
        case R128_PM4_64PIO_128INDBM:
        case R128_PM4_64BM_128INDBM:
        case R128_PM4_64PIO_64VCBM_64INDBM:
        case R128_PM4_64BM_64VCBM_64INDBM:
        case R128_PM4_64PIO_64VCPIO_64INDPIO:
                dev_priv->cce_fifo_size = 64;
                break;
        }

        switch (init->fb_bpp) {
        case 16:
                dev_priv->color_fmt = R128_DATATYPE_RGB565;
                break;
        case 32:
        default:
                dev_priv->color_fmt = R128_DATATYPE_ARGB8888;
                break;
        }
        dev_priv->front_offset = init->front_offset;
        dev_priv->front_pitch = init->front_pitch;
        dev_priv->back_offset = init->back_offset;
        dev_priv->back_pitch = init->back_pitch;

        switch (init->depth_bpp) {
        case 16:
                dev_priv->depth_fmt = R128_DATATYPE_RGB565;
                break;
        case 24:
        case 32:
        default:
                dev_priv->depth_fmt = R128_DATATYPE_ARGB8888;
                break;
        }
        dev_priv->depth_offset = init->depth_offset;
        dev_priv->depth_pitch = init->depth_pitch;
        dev_priv->span_offset = init->span_offset;

        dev_priv->front_pitch_offset_c = (((dev_priv->front_pitch / 8) << 21) |
                                          (dev_priv->front_offset >> 5));
        dev_priv->back_pitch_offset_c = (((dev_priv->back_pitch / 8) << 21) |
                                         (dev_priv->back_offset >> 5));
        dev_priv->depth_pitch_offset_c = (((dev_priv->depth_pitch / 8) << 21) |
                                          (dev_priv->depth_offset >> 5) |
                                          R128_DST_TILE);
        dev_priv->span_pitch_offset_c = (((dev_priv->depth_pitch / 8) << 21) |
                                         (dev_priv->span_offset >> 5));

        dev_priv->sarea = drm_legacy_getsarea(dev);
        if (!dev_priv->sarea) {
                DRM_ERROR("could not find sarea!\n");
                dev->dev_private = (void *)dev_priv;
                r128_do_cleanup_cce(dev);
                return -EINVAL;
        }

        dev_priv->mmio = drm_legacy_findmap(dev, init->mmio_offset);
        if (!dev_priv->mmio) {
                DRM_ERROR("could not find mmio region!\n");
                dev->dev_private = (void *)dev_priv;
                r128_do_cleanup_cce(dev);
                return -EINVAL;
        }
        dev_priv->cce_ring = drm_legacy_findmap(dev, init->ring_offset);
        if (!dev_priv->cce_ring) {
                DRM_ERROR("could not find cce ring region!\n");
                dev->dev_private = (void *)dev_priv;
                r128_do_cleanup_cce(dev);
                return -EINVAL;
        }
        dev_priv->ring_rptr = drm_legacy_findmap(dev, init->ring_rptr_offset);
        if (!dev_priv->ring_rptr) {
                DRM_ERROR("could not find ring read pointer!\n");
                dev->dev_private = (void *)dev_priv;
                r128_do_cleanup_cce(dev);
                return -EINVAL;
        }
        dev->agp_buffer_token = init->buffers_offset;
        dev->agp_buffer_map = drm_legacy_findmap(dev, init->buffers_offset);
        if (!dev->agp_buffer_map) {
                DRM_ERROR("could not find dma buffer region!\n");
                dev->dev_private = (void *)dev_priv;
                r128_do_cleanup_cce(dev);
                return -EINVAL;
        }

        if (!dev_priv->is_pci) {
                dev_priv->agp_textures =
                    drm_legacy_findmap(dev, init->agp_textures_offset);
                if (!dev_priv->agp_textures) {
                        DRM_ERROR("could not find agp texture region!\n");
                        dev->dev_private = (void *)dev_priv;
                        r128_do_cleanup_cce(dev);
                        return -EINVAL;
                }
        }

        dev_priv->sarea_priv =
            (drm_r128_sarea_t *) ((u8 *) dev_priv->sarea->handle +
                                  init->sarea_priv_offset);

#if IS_ENABLED(CONFIG_AGP)
        if (!dev_priv->is_pci) {
                drm_legacy_ioremap_wc(dev_priv->cce_ring, dev);
                drm_legacy_ioremap_wc(dev_priv->ring_rptr, dev);
                drm_legacy_ioremap_wc(dev->agp_buffer_map, dev);
                if (!dev_priv->cce_ring->handle ||
                    !dev_priv->ring_rptr->handle ||
                    !dev->agp_buffer_map->handle) {
                        DRM_ERROR("Could not ioremap agp regions!\n");
                        dev->dev_private = (void *)dev_priv;
                        r128_do_cleanup_cce(dev);
                        return -ENOMEM;
                }
        } else
#endif
        {
                dev_priv->cce_ring->handle =
                        (void *)(unsigned long)dev_priv->cce_ring->offset;
                dev_priv->ring_rptr->handle =
                        (void *)(unsigned long)dev_priv->ring_rptr->offset;
                dev->agp_buffer_map->handle =
                        (void *)(unsigned long)dev->agp_buffer_map->offset;
        }

#if IS_ENABLED(CONFIG_AGP)
        if (!dev_priv->is_pci)
                dev_priv->cce_buffers_offset = dev->agp->base;
        else
#endif
                dev_priv->cce_buffers_offset = (unsigned long)dev->sg->virtual;

        dev_priv->ring.start = (u32 *) dev_priv->cce_ring->handle;
        dev_priv->ring.end = ((u32 *) dev_priv->cce_ring->handle
                              + init->ring_size / sizeof(u32));
        dev_priv->ring.size = init->ring_size;
        dev_priv->ring.size_l2qw = order_base_2(init->ring_size / 8);

        dev_priv->ring.tail_mask = (dev_priv->ring.size / sizeof(u32)) - 1;

        dev_priv->ring.high_mark = 128;

        dev_priv->sarea_priv->last_frame = 0;
        R128_WRITE(R128_LAST_FRAME_REG, dev_priv->sarea_priv->last_frame);

        dev_priv->sarea_priv->last_dispatch = 0;
        R128_WRITE(R128_LAST_DISPATCH_REG, dev_priv->sarea_priv->last_dispatch);

#if IS_ENABLED(CONFIG_AGP)
        if (dev_priv->is_pci) {
#endif
                dev_priv->gart_info.table_mask = DMA_BIT_MASK(32);
                dev_priv->gart_info.gart_table_location = DRM_ATI_GART_MAIN;
                dev_priv->gart_info.table_size = R128_PCIGART_TABLE_SIZE;
                dev_priv->gart_info.addr = NULL;
                dev_priv->gart_info.bus_addr = 0;
                dev_priv->gart_info.gart_reg_if = DRM_ATI_GART_PCI;
                rc = drm_ati_pcigart_init(dev, &dev_priv->gart_info);
                if (rc) {
                        DRM_ERROR("failed to init PCI GART!\n");
                        dev->dev_private = (void *)dev_priv;
                        r128_do_cleanup_cce(dev);
                        return rc;
                }
                R128_WRITE(R128_PCI_GART_PAGE, dev_priv->gart_info.bus_addr);
#if IS_ENABLED(CONFIG_AGP)
        }
#endif

        r128_cce_init_ring_buffer(dev, dev_priv);
        rc = r128_cce_load_microcode(dev_priv);

        dev->dev_private = (void *)dev_priv;

        r128_do_engine_reset(dev);

        if (rc) {
                DRM_ERROR("Failed to load firmware!\n");
                r128_do_cleanup_cce(dev);
        }

        return rc;
}

int r128_do_cleanup_cce(struct drm_device *dev)
{

        /* Make sure interrupts are disabled here because the uninstall ioctl
         * may not have been called from userspace and after dev_private
         * is freed, it's too late.
         */
        if (dev->irq_enabled)
                drm_legacy_irq_uninstall(dev);

        if (dev->dev_private) {
                drm_r128_private_t *dev_priv = dev->dev_private;

#if IS_ENABLED(CONFIG_AGP)
                if (!dev_priv->is_pci) {
                        if (dev_priv->cce_ring != NULL)
                                drm_legacy_ioremapfree(dev_priv->cce_ring, dev);
                        if (dev_priv->ring_rptr != NULL)
                                drm_legacy_ioremapfree(dev_priv->ring_rptr, dev);
                        if (dev->agp_buffer_map != NULL) {
                                drm_legacy_ioremapfree(dev->agp_buffer_map, dev);
                                dev->agp_buffer_map = NULL;
                        }
                } else
#endif
                {
                        if (dev_priv->gart_info.bus_addr)
                                if (!drm_ati_pcigart_cleanup(dev,
                                                        &dev_priv->gart_info))
                                        DRM_ERROR
                                            ("failed to cleanup PCI GART!\n");
                }

                kfree(dev->dev_private);
                dev->dev_private = NULL;
        }

        return 0;
}

int r128_cce_init(struct drm_device *dev, void *data, struct drm_file *file_priv)
{
        drm_r128_init_t *init = data;

        DRM_DEBUG("\n");

        LOCK_TEST_WITH_RETURN(dev, file_priv);

        switch (init->func) {
        case R128_INIT_CCE:
                return r128_do_init_cce(dev, init);
        case R128_CLEANUP_CCE:
                return r128_do_cleanup_cce(dev);
        }

        return -EINVAL;
}

int r128_cce_start(struct drm_device *dev, void *data, struct drm_file *file_priv)
{
        drm_r128_private_t *dev_priv = dev->dev_private;
        DRM_DEBUG("\n");

        LOCK_TEST_WITH_RETURN(dev, file_priv);

        DEV_INIT_TEST_WITH_RETURN(dev_priv);

        if (dev_priv->cce_running || dev_priv->cce_mode == R128_PM4_NONPM4) {
                DRM_DEBUG("while CCE running\n");
                return 0;
        }

        r128_do_cce_start(dev_priv);

        return 0;
}

/* Stop the CCE.  The engine must have been idled before calling this
 * routine.
 */
int r128_cce_stop(struct drm_device *dev, void *data, struct drm_file *file_priv)
{
        drm_r128_private_t *dev_priv = dev->dev_private;
        drm_r128_cce_stop_t *stop = data;
        int ret;
        DRM_DEBUG("\n");

        LOCK_TEST_WITH_RETURN(dev, file_priv);

        DEV_INIT_TEST_WITH_RETURN(dev_priv);

        /* Flush any pending CCE commands.  This ensures any outstanding
         * commands are exectuted by the engine before we turn it off.
         */
        if (stop->flush)
                r128_do_cce_flush(dev_priv);

        /* If we fail to make the engine go idle, we return an error
         * code so that the DRM ioctl wrapper can try again.
         */
        if (stop->idle) {
                ret = r128_do_cce_idle(dev_priv);
                if (ret)
                        return ret;
        }

        /* Finally, we can turn off the CCE.  If the engine isn't idle,
         * we will get some dropped triangles as they won't be fully
         * rendered before the CCE is shut down.
         */
        r128_do_cce_stop(dev_priv);

        /* Reset the engine */
        r128_do_engine_reset(dev);

        return 0;
}

/* Just reset the CCE ring.  Called as part of an X Server engine reset.
 */
int r128_cce_reset(struct drm_device *dev, void *data, struct drm_file *file_priv)
{
        drm_r128_private_t *dev_priv = dev->dev_private;
        DRM_DEBUG("\n");

        LOCK_TEST_WITH_RETURN(dev, file_priv);

        DEV_INIT_TEST_WITH_RETURN(dev_priv);

        r128_do_cce_reset(dev_priv);

        /* The CCE is no longer running after an engine reset */
        dev_priv->cce_running = 0;

        return 0;
}

int r128_cce_idle(struct drm_device *dev, void *data, struct drm_file *file_priv)
{
        drm_r128_private_t *dev_priv = dev->dev_private;
        DRM_DEBUG("\n");

        LOCK_TEST_WITH_RETURN(dev, file_priv);

        DEV_INIT_TEST_WITH_RETURN(dev_priv);

        if (dev_priv->cce_running)
                r128_do_cce_flush(dev_priv);

        return r128_do_cce_idle(dev_priv);
}

int r128_engine_reset(struct drm_device *dev, void *data, struct drm_file *file_priv)
{
        DRM_DEBUG("\n");

        LOCK_TEST_WITH_RETURN(dev, file_priv);

        DEV_INIT_TEST_WITH_RETURN(dev->dev_private);

        return r128_do_engine_reset(dev);
}

int r128_fullscreen(struct drm_device *dev, void *data, struct drm_file *file_priv)
{
        return -EINVAL;
}

/* ================================================================
 * Freelist management
 */
#define R128_BUFFER_USED        0xffffffff
#define R128_BUFFER_FREE        0

#if 0
static int r128_freelist_init(struct drm_device *dev)
{
        struct drm_device_dma *dma = dev->dma;
        drm_r128_private_t *dev_priv = dev->dev_private;
        struct drm_buf *buf;
        drm_r128_buf_priv_t *buf_priv;
        drm_r128_freelist_t *entry;
        int i;

        dev_priv->head = kzalloc(sizeof(drm_r128_freelist_t), GFP_KERNEL);
        if (dev_priv->head == NULL)
                return -ENOMEM;

        dev_priv->head->age = R128_BUFFER_USED;

        for (i = 0; i < dma->buf_count; i++) {
                buf = dma->buflist[i];
                buf_priv = buf->dev_private;

                entry = kmalloc(sizeof(drm_r128_freelist_t), GFP_KERNEL);
                if (!entry)
                        return -ENOMEM;

                entry->age = R128_BUFFER_FREE;
                entry->buf = buf;
                entry->prev = dev_priv->head;
                entry->next = dev_priv->head->next;
                if (!entry->next)
                        dev_priv->tail = entry;

                buf_priv->discard = 0;
                buf_priv->dispatched = 0;
                buf_priv->list_entry = entry;

                dev_priv->head->next = entry;

                if (dev_priv->head->next)
                        dev_priv->head->next->prev = entry;
        }

        return 0;

}
#endif

static struct drm_buf *r128_freelist_get(struct drm_device * dev)
{
        struct drm_device_dma *dma = dev->dma;
        drm_r128_private_t *dev_priv = dev->dev_private;
        drm_r128_buf_priv_t *buf_priv;
        struct drm_buf *buf;
        int i, t;

        /* FIXME: Optimize -- use freelist code */

        for (i = 0; i < dma->buf_count; i++) {
                buf = dma->buflist[i];
                buf_priv = buf->dev_private;
                if (!buf->file_priv)
                        return buf;
        }

        for (t = 0; t < dev_priv->usec_timeout; t++) {
                u32 done_age = R128_READ(R128_LAST_DISPATCH_REG);

                for (i = 0; i < dma->buf_count; i++) {
                        buf = dma->buflist[i];
                        buf_priv = buf->dev_private;
                        if (buf->pending && buf_priv->age <= done_age) {
                                /* The buffer has been processed, so it
                                 * can now be used.
                                 */
                                buf->pending = 0;
                                return buf;
                        }
                }
                udelay(1);
        }

        DRM_DEBUG("returning NULL!\n");
        return NULL;
}

void r128_freelist_reset(struct drm_device *dev)
{
        struct drm_device_dma *dma = dev->dma;
        int i;

        for (i = 0; i < dma->buf_count; i++) {
                struct drm_buf *buf = dma->buflist[i];
                drm_r128_buf_priv_t *buf_priv = buf->dev_private;
                buf_priv->age = 0;
        }
}

/* ================================================================
 * CCE command submission
 */

int r128_wait_ring(drm_r128_private_t *dev_priv, int n)
{
        drm_r128_ring_buffer_t *ring = &dev_priv->ring;
        int i;

        for (i = 0; i < dev_priv->usec_timeout; i++) {
                r128_update_ring_snapshot(dev_priv);
                if (ring->space >= n)
                        return 0;
                udelay(1);
        }

        /* FIXME: This is being ignored... */
        DRM_ERROR("failed!\n");
        return -EBUSY;
}

static int r128_cce_get_buffers(struct drm_device *dev,
                                struct drm_file *file_priv,
                                struct drm_dma *d)
{
        int i;
        struct drm_buf *buf;

        for (i = d->granted_count; i < d->request_count; i++) {
                buf = r128_freelist_get(dev);
                if (!buf)
                        return -EAGAIN;

                buf->file_priv = file_priv;

                if (copy_to_user(&d->request_indices[i], &buf->idx,
                                     sizeof(buf->idx)))
                        return -EFAULT;
                if (copy_to_user(&d->request_sizes[i], &buf->total,
                                     sizeof(buf->total)))
                        return -EFAULT;

                d->granted_count++;
        }
        return 0;
}

int r128_cce_buffers(struct drm_device *dev, void *data, struct drm_file *file_priv)
{
        struct drm_device_dma *dma = dev->dma;
        int ret = 0;
        struct drm_dma *d = data;

        LOCK_TEST_WITH_RETURN(dev, file_priv);

        /* Please don't send us buffers.
         */
        if (d->send_count != 0) {
                DRM_ERROR("Process %d trying to send %d buffers via drmDMA\n",
                          task_pid_nr(current), d->send_count);
                return -EINVAL;
        }

        /* We'll send you buffers.
         */
        if (d->request_count < 0 || d->request_count > dma->buf_count) {
                DRM_ERROR("Process %d trying to get %d buffers (of %d max)\n",
                          task_pid_nr(current), d->request_count, dma->buf_count);
                return -EINVAL;
        }

        d->granted_count = 0;

        if (d->request_count)
                ret = r128_cce_get_buffers(dev, file_priv, d);

        return ret;
}