1 files changed, 300 insertions, 0 deletions
diff --git a/drivers/gpu/drm/bochs/bochs_hw.c b/drivers/gpu/drm/bochs/bochs_hw.c
new file mode 100644
index 000000000..dce4672e3
--- /dev/null
+++ b/drivers/gpu/drm/bochs/bochs_hw.c
@@ -0,0 +1,300 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ */
+
+#include <linux/pci.h>
+
+#include <drm/drm_drv.h>
+#include <drm/drm_fourcc.h>
+
+#include "bochs.h"
+
+/* ---------------------------------------------------------------------- */
+
+static void bochs_vga_writeb(struct bochs_device *bochs, u16 ioport, u8 val)
+{
+	if (WARN_ON(ioport < 0x3c0 || ioport > 0x3df))
+		return;
+
+	if (bochs->mmio) {
+		int offset = ioport - 0x3c0 + 0x400;
+		writeb(val, bochs->mmio + offset);
+	} else {
+		outb(val, ioport);
+	}
+}
+
+static u16 bochs_dispi_read(struct bochs_device *bochs, u16 reg)
+{
+	u16 ret = 0;
+
+	if (bochs->mmio) {
+		int offset = 0x500 + (reg << 1);
+		ret = readw(bochs->mmio + offset);
+	} else {
+		outw(reg, VBE_DISPI_IOPORT_INDEX);
+		ret = inw(VBE_DISPI_IOPORT_DATA);
+	}
+	return ret;
+}
+
+static void bochs_dispi_write(struct bochs_device *bochs, u16 reg, u16 val)
+{
+	if (bochs->mmio) {
+		int offset = 0x500 + (reg << 1);
+		writew(val, bochs->mmio + offset);
+	} else {
+		outw(reg, VBE_DISPI_IOPORT_INDEX);
+		outw(val, VBE_DISPI_IOPORT_DATA);
+	}
+}
+
+static void bochs_hw_set_big_endian(struct bochs_device *bochs)
+{
+	if (bochs->qext_size < 8)
+		return;
+
+	writel(0xbebebebe, bochs->mmio + 0x604);
+}
+
+static void bochs_hw_set_little_endian(struct bochs_device *bochs)
+{
+	if (bochs->qext_size < 8)
+		return;
+
+	writel(0x1e1e1e1e, bochs->mmio + 0x604);
+}
+
+#ifdef __BIG_ENDIAN
+#define bochs_hw_set_native_endian(_b) bochs_hw_set_big_endian(_b)
+#else
+#define bochs_hw_set_native_endian(_b) bochs_hw_set_little_endian(_b)
+#endif
+
+static int bochs_get_edid_block(void *data, u8 *buf,
+				unsigned int block, size_t len)
+{
+	struct bochs_device *bochs = data;
+	size_t i, start = block * EDID_LENGTH;
+
+	if (start + len > 0x400 /* vga register offset */)
+		return -1;
+
+	for (i = 0; i < len; i++) {
+		buf[i] = readb(bochs->mmio + start + i);
+	}
+	return 0;
+}
+
+int bochs_hw_load_edid(struct bochs_device *bochs)
+{
+	u8 header[8];
+
+	if (!bochs->mmio)
+		return -1;
+
+	/* check header to detect whenever edid support is enabled in qemu */
+	bochs_get_edid_block(bochs, header, 0, ARRAY_SIZE(header));
+	if (drm_edid_header_is_valid(header) != 8)
+		return -1;
+
+	kfree(bochs->edid);
+	bochs->edid = drm_do_get_edid(&bochs->connector,
+				      bochs_get_edid_block, bochs);
+	if (bochs->edid == NULL)
+		return -1;
+
+	return 0;
+}
+
+int bochs_hw_init(struct drm_device *dev)
+{
+	struct bochs_device *bochs = dev->dev_private;
+	struct pci_dev *pdev = dev->pdev;
+	unsigned long addr, size, mem, ioaddr, iosize;
+	u16 id;
+
+	if (pdev->resource[2].flags & IORESOURCE_MEM) {
+		/* mmio bar with vga and bochs registers present */
+		if (pci_request_region(pdev, 2, "bochs-drm") != 0) {
+			DRM_ERROR("Cannot request mmio region\n");
+			return -EBUSY;
+		}
+		ioaddr = pci_resource_start(pdev, 2);
+		iosize = pci_resource_len(pdev, 2);
+		bochs->mmio = ioremap(ioaddr, iosize);
+		if (bochs->mmio == NULL) {
+			DRM_ERROR("Cannot map mmio region\n");
+			return -ENOMEM;
+		}
+	} else {
+		ioaddr = VBE_DISPI_IOPORT_INDEX;
+		iosize = 2;
+		if (!request_region(ioaddr, iosize, "bochs-drm")) {
+			DRM_ERROR("Cannot request ioports\n");
+			return -EBUSY;
+		}
+		bochs->ioports = 1;
+	}
+
+	id = bochs_dispi_read(bochs, VBE_DISPI_INDEX_ID);
+	mem = bochs_dispi_read(bochs, VBE_DISPI_INDEX_VIDEO_MEMORY_64K)
+		* 64 * 1024;
+	if ((id & 0xfff0) != VBE_DISPI_ID0) {
+		DRM_ERROR("ID mismatch\n");
+		return -ENODEV;
+	}
+
+	if ((pdev->resource[0].flags & IORESOURCE_MEM) == 0)
+		return -ENODEV;
+	addr = pci_resource_start(pdev, 0);
+	size = pci_resource_len(pdev, 0);
+	if (addr == 0)
+		return -ENODEV;
+	if (size != mem) {
+		DRM_ERROR("Size mismatch: pci=%ld, bochs=%ld\n",
+			size, mem);
+		size = min(size, mem);
+	}
+
+	if (pci_request_region(pdev, 0, "bochs-drm") != 0)
+		DRM_WARN("Cannot request framebuffer, boot fb still active?\n");
+
+	bochs->fb_map = ioremap(addr, size);
+	if (bochs->fb_map == NULL) {
+		DRM_ERROR("Cannot map framebuffer\n");
+		return -ENOMEM;
+	}
+	bochs->fb_base = addr;
+	bochs->fb_size = size;
+
+	DRM_INFO("Found bochs VGA, ID 0x%x.\n", id);
+	DRM_INFO("Framebuffer size %ld kB @ 0x%lx, %s @ 0x%lx.\n",
+		 size / 1024, addr,
+		 bochs->ioports ? "ioports" : "mmio",
+		 ioaddr);
+
+	if (bochs->mmio && pdev->revision >= 2) {
+		bochs->qext_size = readl(bochs->mmio + 0x600);
+		if (bochs->qext_size < 4 || bochs->qext_size > iosize) {
+			bochs->qext_size = 0;
+			goto noext;
+		}
+		DRM_DEBUG("Found qemu ext regs, size %ld\n",
+			  bochs->qext_size);
+		bochs_hw_set_native_endian(bochs);
+	}
+
+noext:
+	return 0;
+}
+
+void bochs_hw_fini(struct drm_device *dev)
+{
+	struct bochs_device *bochs = dev->dev_private;
+
+	/* TODO: shot down existing vram mappings */
+
+	if (bochs->mmio)
+		iounmap(bochs->mmio);
+	if (bochs->ioports)
+		release_region(VBE_DISPI_IOPORT_INDEX, 2);
+	if (bochs->fb_map)
+		iounmap(bochs->fb_map);
+	pci_release_regions(dev->pdev);
+	kfree(bochs->edid);
+}
+
+void bochs_hw_setmode(struct bochs_device *bochs,
+		      struct drm_display_mode *mode)
+{
+	int idx;
+
+	if (!drm_dev_enter(bochs->dev, &idx))
+		return;
+
+	bochs->xres = mode->hdisplay;
+	bochs->yres = mode->vdisplay;
+	bochs->bpp = 32;
+	bochs->stride = mode->hdisplay * (bochs->bpp / 8);
+	bochs->yres_virtual = bochs->fb_size / bochs->stride;
+
+	DRM_DEBUG_DRIVER("%dx%d @ %d bpp, vy %d\n",
+			 bochs->xres, bochs->yres, bochs->bpp,
+			 bochs->yres_virtual);
+
+	bochs_vga_writeb(bochs, 0x3c0, 0x20); /* unblank */
+
+	bochs_dispi_write(bochs, VBE_DISPI_INDEX_ENABLE,      0);
+	bochs_dispi_write(bochs, VBE_DISPI_INDEX_BPP,         bochs->bpp);
+	bochs_dispi_write(bochs, VBE_DISPI_INDEX_XRES,        bochs->xres);
+	bochs_dispi_write(bochs, VBE_DISPI_INDEX_YRES,        bochs->yres);
+	bochs_dispi_write(bochs, VBE_DISPI_INDEX_BANK,        0);
+	bochs_dispi_write(bochs, VBE_DISPI_INDEX_VIRT_WIDTH,  bochs->xres);
+	bochs_dispi_write(bochs, VBE_DISPI_INDEX_VIRT_HEIGHT,
+			  bochs->yres_virtual);
+	bochs_dispi_write(bochs, VBE_DISPI_INDEX_X_OFFSET,    0);
+	bochs_dispi_write(bochs, VBE_DISPI_INDEX_Y_OFFSET,    0);
+
+	bochs_dispi_write(bochs, VBE_DISPI_INDEX_ENABLE,
+			  VBE_DISPI_ENABLED | VBE_DISPI_LFB_ENABLED);
+
+	drm_dev_exit(idx);
+}
+
+void bochs_hw_setformat(struct bochs_device *bochs,
+			const struct drm_format_info *format)
+{
+	int idx;
+
+	if (!drm_dev_enter(bochs->dev, &idx))
+		return;
+
+	DRM_DEBUG_DRIVER("format %c%c%c%c\n",
+			 (format->format >>  0) & 0xff,
+			 (format->format >>  8) & 0xff,
+			 (format->format >> 16) & 0xff,
+			 (format->format >> 24) & 0xff);
+
+	switch (format->format) {
+	case DRM_FORMAT_XRGB8888:
+		bochs_hw_set_little_endian(bochs);
+		break;
+	case DRM_FORMAT_BGRX8888:
+		bochs_hw_set_big_endian(bochs);
+		break;
+	default:
+		/* should not happen */
+		DRM_ERROR("%s: Huh? Got framebuffer format 0x%x",
+			  __func__, format->format);
+		break;
+	}
+
+	drm_dev_exit(idx);
+}
+
+void bochs_hw_setbase(struct bochs_device *bochs,
+		      int x, int y, int stride, u64 addr)
+{
+	unsigned long offset;
+	unsigned int vx, vy, vwidth, idx;
+
+	if (!drm_dev_enter(bochs->dev, &idx))
+		return;
+
+	bochs->stride = stride;
+	offset = (unsigned long)addr +
+		y * bochs->stride +
+		x * (bochs->bpp / 8);
+	vy = offset / bochs->stride;
+	vx = (offset % bochs->stride) * 8 / bochs->bpp;
+	vwidth = stride * 8 / bochs->bpp;
+
+	DRM_DEBUG_DRIVER("x %d, y %d, addr %llx -> offset %lx, vx %d, vy %d\n",
+			 x, y, addr, offset, vx, vy);
+	bochs_dispi_write(bochs, VBE_DISPI_INDEX_VIRT_WIDTH, vwidth);
+	bochs_dispi_write(bochs, VBE_DISPI_INDEX_X_OFFSET, vx);
+	bochs_dispi_write(bochs, VBE_DISPI_INDEX_Y_OFFSET, vy);
+
+	drm_dev_exit(idx);
+}