hw/display: Add basic ATI VGA emulation

At least two machines, the PPC mac99 and MIPS fulong2e, have an ATI
gfx chip by default (Rage 128 Pro and M6/RV100 respectively) and
guests running on these and the PMON2000 firmware of the fulong2e
expect this to be available. Fortunately these are very similar chips
so they can be mostly emulated in the same device model. This patch
adds basic emulation of these ATI VGA chips.

While this is incomplete and currently only enough to run the MIPS
firmware and get framebuffer output with Linux, it allows the fulong2e
board to work more like the real hardware and having it in QEMU in
this state provides a way to experiment with it and allows others to
contribute to improve it. It is compiled for all archs but only the
fulong2e (which currently has no display output at all) is set to use
it by default (in a separate patch).

Signed-off-by: BALATON Zoltan <balaton@eik.bme.hu>
Acked-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Tested-by: Andrew Randrianasulu <randrianasulu@gmail.com>
Tested-by: Howard Spoelstra <hsp.cat7@gmail.com>
Message-id: 0b1b7c22873a6e37627261b04fb687412b25ff4f.1552152100.git.balaton@eik.bme.hu
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

1 files changed, 167 insertions, 0 deletions

diff --git a/hw/display/ati_2d.c b/hw/display/ati_2d.c
new file mode 100644
index 0000000000..bc98ba6eeb
--- /dev/null
+++ b/hw/display/ati_2d.c
@@ -0,0 +1,167 @@
+/*
+ * QEMU ATI SVGA emulation
+ * 2D engine functions
+ *
+ * Copyright (c) 2019 BALATON Zoltan
+ *
+ * This work is licensed under the GNU GPL license version 2 or later.
+ */
+
+#include "ati_int.h"
+#include "ati_regs.h"
+#include "qemu/log.h"
+#include "ui/pixel_ops.h"
+
+/*
+ * NOTE:
+ * This is 2D _acceleration_ and supposed to be fast. Therefore, don't try to
+ * reinvent the wheel (unlikely to get better with a naive implementation than
+ * existing libraries) and avoid (poorly) reimplementing gfx primitives.
+ * That is unnecessary and would become a performance problem. Instead, try to
+ * map to and reuse existing optimised facilities (e.g. pixman) wherever
+ * possible.
+ */
+
+static int ati_bpp_from_datatype(ATIVGAState *s)
+{
+    switch (s->regs.dp_datatype & 0xf) {
+    case 2:
+        return 8;
+    case 3:
+    case 4:
+        return 16;
+    case 5:
+        return 24;
+    case 6:
+        return 32;
+    default:
+        qemu_log_mask(LOG_UNIMP, "Unknown dst datatype %d\n",
+                      s->regs.dp_datatype & 0xf);
+        return 0;
+    }
+}
+
+void ati_2d_blt(ATIVGAState *s)
+{
+    /* FIXME it is probably more complex than this and may need to be */
+    /* rewritten but for now as a start just to get some output: */
+    DisplaySurface *ds = qemu_console_surface(s->vga.con);
+    DPRINTF("%p %u ds: %p %d %d rop: %x\n", s->vga.vram_ptr,
+            s->vga.vbe_start_addr, surface_data(ds), surface_stride(ds),
+            surface_bits_per_pixel(ds),
+            (s->regs.dp_mix & GMC_ROP3_MASK) >> 16);
+    DPRINTF("%d %d, %d %d, (%d,%d) -> (%d,%d) %dx%d\n", s->regs.src_offset,
+            s->regs.dst_offset, s->regs.src_pitch, s->regs.dst_pitch,
+            s->regs.src_x, s->regs.src_y, s->regs.dst_x, s->regs.dst_y,
+            s->regs.dst_width, s->regs.dst_height);
+    switch (s->regs.dp_mix & GMC_ROP3_MASK) {
+    case ROP3_SRCCOPY:
+    {
+        uint8_t *src_bits, *dst_bits, *end;
+        int src_stride, dst_stride, bpp = ati_bpp_from_datatype(s);
+        src_bits = s->vga.vram_ptr + s->regs.src_offset;
+        dst_bits = s->vga.vram_ptr + s->regs.dst_offset;
+        src_stride = s->regs.src_pitch;
+        dst_stride = s->regs.dst_pitch;
+
+        if (s->dev_id == PCI_DEVICE_ID_ATI_RAGE128_PF) {
+            src_bits += s->regs.crtc_offset & 0x07ffffff;
+            dst_bits += s->regs.crtc_offset & 0x07ffffff;
+            src_stride *= bpp;
+            dst_stride *= bpp;
+        }
+        src_stride /= sizeof(uint32_t);
+        dst_stride /= sizeof(uint32_t);
+
+        DPRINTF("pixman_blt(%p, %p, %d, %d, %d, %d, %d, %d, %d, %d, %d, %d)\n",
+                src_bits, dst_bits, src_stride, dst_stride, bpp, bpp,
+                s->regs.src_x, s->regs.src_y, s->regs.dst_x, s->regs.dst_y,
+                s->regs.dst_width, s->regs.dst_height);
+        end = s->vga.vram_ptr + s->vga.vram_size;
+        if (src_bits >= end || dst_bits >= end ||
+            src_bits + (s->regs.src_y + s->regs.dst_height) * src_stride +
+            s->regs.src_x >= end ||
+            dst_bits + (s->regs.dst_y + s->regs.dst_height) * dst_stride +
+            s->regs.dst_x >= end) {
+            qemu_log_mask(LOG_UNIMP, "blt outside vram not implemented\n");
+            return;
+        }
+        pixman_blt((uint32_t *)src_bits, (uint32_t *)dst_bits,
+                   src_stride, dst_stride, bpp, bpp,
+                   s->regs.src_x, s->regs.src_y,
+                   s->regs.dst_x, s->regs.dst_y,
+                   s->regs.dst_width, s->regs.dst_height);
+        if (dst_bits >= s->vga.vram_ptr + s->vga.vbe_start_addr &&
+            dst_bits < s->vga.vram_ptr + s->vga.vbe_start_addr +
+            s->vga.vbe_regs[VBE_DISPI_INDEX_YRES] * s->vga.vbe_line_offset) {
+            memory_region_set_dirty(&s->vga.vram, s->vga.vbe_start_addr +
+                                    s->regs.dst_offset +
+                                    s->regs.dst_y * surface_stride(ds),
+                                    s->regs.dst_height * surface_stride(ds));
+        }
+        s->regs.dst_x += s->regs.dst_width;
+        s->regs.dst_y += s->regs.dst_height;
+        break;
+    }
+    case ROP3_PATCOPY:
+    case ROP3_BLACKNESS:
+    case ROP3_WHITENESS:
+    {
+        uint8_t *dst_bits, *end;
+        int dst_stride, bpp = ati_bpp_from_datatype(s);
+        uint32_t filler = 0;
+        dst_bits = s->vga.vram_ptr + s->regs.dst_offset;
+        dst_stride = s->regs.dst_pitch;
+
+        if (s->dev_id == PCI_DEVICE_ID_ATI_RAGE128_PF) {
+            dst_bits += s->regs.crtc_offset & 0x07ffffff;
+            dst_stride *= bpp;
+        }
+        dst_stride /= sizeof(uint32_t);
+
+        switch (s->regs.dp_mix & GMC_ROP3_MASK) {
+        case ROP3_PATCOPY:
+            filler = bswap32(s->regs.dp_brush_frgd_clr);
+            break;
+        case ROP3_BLACKNESS:
+            filler = rgb_to_pixel32(s->vga.palette[0], s->vga.palette[1],
+                                    s->vga.palette[2]) << 8 | 0xff;
+            break;
+        case ROP3_WHITENESS:
+            filler = rgb_to_pixel32(s->vga.palette[3], s->vga.palette[4],
+                                    s->vga.palette[5]) << 8 | 0xff;
+            break;
+        }
+
+        DPRINTF("pixman_fill(%p, %d, %d, %d, %d, %d, %d, %x)\n",
+                dst_bits, dst_stride, bpp,
+                s->regs.dst_x, s->regs.dst_y,
+                s->regs.dst_width, s->regs.dst_height,
+                filler);
+        end = s->vga.vram_ptr + s->vga.vram_size;
+        if (dst_bits >= end ||
+            dst_bits + (s->regs.dst_y + s->regs.dst_height) * dst_stride +
+            s->regs.dst_x >= end) {
+            qemu_log_mask(LOG_UNIMP, "blt outside vram not implemented\n");
+            return;
+        }
+        pixman_fill((uint32_t *)dst_bits, dst_stride, bpp,
+                   s->regs.dst_x, s->regs.dst_y,
+                   s->regs.dst_width, s->regs.dst_height,
+                   filler);
+        if (dst_bits >= s->vga.vram_ptr + s->vga.vbe_start_addr &&
+            dst_bits < s->vga.vram_ptr + s->vga.vbe_start_addr +
+            s->vga.vbe_regs[VBE_DISPI_INDEX_YRES] * s->vga.vbe_line_offset) {
+            memory_region_set_dirty(&s->vga.vram, s->vga.vbe_start_addr +
+                                    s->regs.dst_offset +
+                                    s->regs.dst_y * surface_stride(ds),
+                                    s->regs.dst_height * surface_stride(ds));
+        }
+        s->regs.dst_y += s->regs.dst_height;
+        break;
+    }
+    default:
+        qemu_log_mask(LOG_UNIMP, "Unimplemented ati_2d blt op %x\n",
+                      (s->regs.dp_mix & GMC_ROP3_MASK) >> 16);
+    }
+}