Add support for PCI MGA cards to MGA DRM.

This patch adds serveral new ioctls and a new query to get_param query to
support PCI MGA cards.

Two ioctls were added to implement interrupt based waiting.  With this change,
the client-side driver no longer needs to map the primary DMA region or the
MMIO region.  Previously, end-of-frame waiting was done by busy waiting in the
client-side driver until one of the MMIO registers (the current DMA pointer)
matched a pointer to the end of primary DMA space.  By using interrupts, the
busy waiting and the extra mappings are removed.

A third ioctl was added to bootstrap DMA.  This ioctl, which is used by the
X-server, moves a *LOT* of code from the X-server into the kernel.  This allows
the kernel to do whatever needs to be done to setup DMA buffers.  The entire
process and the locations of the buffers are hidden from user-mode.

Additionally, a get_param query was added to differentiate between G4x0 cards
and G550 cards.  A gap was left in the numbering sequence so that, if needed,
G450 cards could be distinguished from G400 cards.  According to Ville
Syrjälä, the G4x0 cards and the G550 cards handle anisotropic filtering
differently.  This seems the most compatible way to let the client-side driver
know which card it's own.  Doing this very small change now eliminates the
need to bump the DRM minor version twice.

http://marc.theaimsgroup.com/?l=dri-devel&m=106625815319773&w=2

(airlied - this may not work at this point, I think the follow on buffer
 cleanup patches will be needed)

From: Ian Romanick <idr@us.ibm.com>
Signed-off-by: Dave Airlie <airlied@linux.ie>

1 files changed, 85 insertions, 10 deletions

diff --git a/drivers/char/drm/mga_drm.h b/drivers/char/drm/mga_drm.h
index 4500e6e4920..2d8aa790379 100644
--- a/drivers/char/drm/mga_drm.h
+++ b/drivers/char/drm/mga_drm.h
@@ -226,10 +226,6 @@ typedef struct _drm_mga_sarea {
 } drm_mga_sarea_t;
 
 
-/* WARNING: If you change any of these defines, make sure to change the
- * defines in the Xserver file (xf86drmMga.h)
- */
-
 /* MGA specific ioctls
  * The device specific ioctl range is 0x40 to 0x79.
  */
@@ -244,6 +240,14 @@ typedef struct _drm_mga_sarea {
 #define DRM_MGA_BLIT     0x08
 #define DRM_MGA_GETPARAM 0x09
 
+/* 3.2:
+ * ioctls for operating on fences.
+ */
+#define DRM_MGA_SET_FENCE      0x0a
+#define DRM_MGA_WAIT_FENCE     0x0b
+#define DRM_MGA_DMA_BOOTSTRAP  0x0c
+
+
 #define DRM_IOCTL_MGA_INIT     DRM_IOW( DRM_COMMAND_BASE + DRM_MGA_INIT, drm_mga_init_t)
 #define DRM_IOCTL_MGA_FLUSH    DRM_IOW( DRM_COMMAND_BASE + DRM_MGA_FLUSH, drm_lock_t)
 #define DRM_IOCTL_MGA_RESET    DRM_IO(  DRM_COMMAND_BASE + DRM_MGA_RESET)
@@ -254,6 +258,9 @@ typedef struct _drm_mga_sarea {
 #define DRM_IOCTL_MGA_ILOAD    DRM_IOW( DRM_COMMAND_BASE + DRM_MGA_ILOAD, drm_mga_iload_t)
 #define DRM_IOCTL_MGA_BLIT     DRM_IOW( DRM_COMMAND_BASE + DRM_MGA_BLIT, drm_mga_blit_t)
 #define DRM_IOCTL_MGA_GETPARAM DRM_IOWR(DRM_COMMAND_BASE + DRM_MGA_GETPARAM, drm_mga_getparam_t)
+#define DRM_IOCTL_MGA_SET_FENCE     DRM_IOW( DRM_COMMAND_BASE + DRM_MGA_SET_FENCE, uint32_t)
+#define DRM_IOCTL_MGA_WAIT_FENCE    DRM_IOWR(DRM_COMMAND_BASE + DRM_MGA_WAIT_FENCE, uint32_t)
+#define DRM_IOCTL_MGA_DMA_BOOTSTRAP DRM_IOWR(DRM_COMMAND_BASE + DRM_MGA_DMA_BOOTSTRAP, drm_mga_dma_bootstrap_t)
 
 typedef struct _drm_mga_warp_index {
    	int installed;
@@ -292,12 +299,72 @@ typedef struct drm_mga_init {
 	unsigned long buffers_offset;
 } drm_mga_init_t;
 
-typedef struct drm_mga_fullscreen {
-	enum {
-		MGA_INIT_FULLSCREEN    = 0x01,
-		MGA_CLEANUP_FULLSCREEN = 0x02
-	} func;
-} drm_mga_fullscreen_t;
+typedef struct drm_mga_dma_bootstrap {
+	/**
+	 * \name AGP texture region
+	 * 
+	 * On return from the DRM_MGA_DMA_BOOTSTRAP ioctl, these fields will
+	 * be filled in with the actual AGP texture settings.
+	 * 
+	 * \warning
+	 * If these fields are non-zero, but dma_mga_dma_bootstrap::agp_mode
+	 * is zero, it means that PCI memory (most likely through the use of
+	 * an IOMMU) is being used for "AGP" textures.
+	 */
+	/*@{*/
+	drm_handle_t texture_handle;  /**< Handle used to map AGP textures. */
+	uint32_t     texture_size;    /**< Size of the AGP texture region. */
+	/*@}*/
+
+
+	/**
+	 * Requested size of the primary DMA region.
+	 * 
+	 * On return from the DRM_MGA_DMA_BOOTSTRAP ioctl, this field will be
+	 * filled in with the actual AGP mode.  If AGP was not available
+	 */
+	uint32_t primary_size;
+
+
+	/**
+	 * Requested number of secondary DMA buffers.
+	 * 
+	 * On return from the DRM_MGA_DMA_BOOTSTRAP ioctl, this field will be
+	 * filled in with the actual number of secondary DMA buffers
+	 * allocated.  Particularly when PCI DMA is used, this may be
+	 * (subtantially) less than the number requested.
+	 */
+	uint32_t secondary_bin_count;
+	
+	
+	/**
+	 * Requested size of each secondary DMA buffer.
+	 * 
+	 * While the kernel \b is free to reduce
+	 * dma_mga_dma_bootstrap::secondary_bin_count, it is \b not allowed
+	 * to reduce dma_mga_dma_bootstrap::secondary_bin_size.
+	 */
+	uint32_t secondary_bin_size;
+
+
+	/**
+	 * Bit-wise mask of AGPSTAT2_* values.  Currently only \c AGPSTAT2_1X,
+	 * \c AGPSTAT2_2X, and \c AGPSTAT2_4X are supported.  If this value is
+	 * zero, it means that PCI DMA should be used, even if AGP is
+	 * possible.
+	 * 
+	 * On return from the DRM_MGA_DMA_BOOTSTRAP ioctl, this field will be
+	 * filled in with the actual AGP mode.  If AGP was not available
+	 * (i.e., PCI DMA was used), this value will be zero.
+	 */
+	uint32_t agp_mode;
+
+
+	/**
+	 * Desired AGP GART size, measured in megabytes.
+	 */
+	uint8_t agp_size;
+} drm_mga_dma_bootstrap_t;
 
 typedef struct drm_mga_clear {
 	unsigned int flags;
@@ -342,6 +409,14 @@ typedef struct _drm_mga_blit {
  */
 #define MGA_PARAM_IRQ_NR            1
 
+/* 3.2: Query the actual card type.  The DDX only distinguishes between
+ * G200 chips and non-G200 chips, which it calls G400.  It turns out that
+ * there are some very sublte differences between the G4x0 chips and the G550
+ * chips.  Using this parameter query, a client-side driver can detect the
+ * difference between a G4x0 and a G550.
+ */
+#define MGA_PARAM_CARD_TYPE         2
+
 typedef struct drm_mga_getparam {
 	int param;
 	void __user *value;