drm/radeon: introduce kernel modesetting for radeon hardware

Add kernel modesetting support to radeon driver, use the ttm memory
manager to manage memory and DRM/GEM to provide userspace API.
In order to avoid backward compatibility issue and to allow clean
design and code the radeon kernel modesetting use different code path
than old radeon/drm driver.

When kernel modesetting is enabled the IOCTL of radeon/drm
driver are considered as invalid and an error message is printed
in the log and they return failure.

KMS enabled userspace will use new API to talk with the radeon/drm
driver. The new API provide functions to create/destroy/share/mmap
buffer object which are then managed by the kernel memory manager
(here TTM). In order to submit command to the GPU the userspace
provide a buffer holding the command stream, along this buffer
userspace have to provide a list of buffer object used by the
command stream. The kernel radeon driver will then place buffer
in GPU accessible memory and will update command stream to reflect
the position of the different buffers.

The kernel will also perform security check on command stream
provided by the user, we want to catch and forbid any illegal use
of the GPU such as DMA into random system memory or into memory
not owned by the process supplying the command stream. This part
of the code is still incomplete and this why we propose that patch
as a staging driver addition, future security might forbid current
experimental userspace to run.

This code support the following hardware : R1XX,R2XX,R3XX,R4XX,R5XX
(radeon up to X1950). Works is underway to provide support for R6XX,
R7XX and newer hardware (radeon from HD2XXX to HD4XXX).

Authors:
    Jerome Glisse <jglisse@redhat.com>
    Dave Airlie <airlied@redhat.com>
    Alex Deucher <alexdeucher@gmail.com>

Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 1215 insertions, 0 deletions

diff --git a/drivers/gpu/drm/radeon/atom.c b/drivers/gpu/drm/radeon/atom.c
new file mode 100644
index 0000000..901befe
--- /dev/null
+++ b/drivers/gpu/drm/radeon/atom.c
@@ -0,0 +1,1215 @@
+/*
+ * Copyright 2008 Advanced Micro Devices, Inc.
+ *
+ * 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 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
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) 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.
+ *
+ * Author: Stanislaw Skowronek
+ */
+
+#include <linux/module.h>
+#include <linux/sched.h>
+
+#define ATOM_DEBUG
+
+#include "atom.h"
+#include "atom-names.h"
+#include "atom-bits.h"
+
+#define ATOM_COND_ABOVE		0
+#define ATOM_COND_ABOVEOREQUAL	1
+#define ATOM_COND_ALWAYS	2
+#define ATOM_COND_BELOW		3
+#define ATOM_COND_BELOWOREQUAL	4
+#define ATOM_COND_EQUAL		5
+#define ATOM_COND_NOTEQUAL	6
+
+#define ATOM_PORT_ATI	0
+#define ATOM_PORT_PCI	1
+#define ATOM_PORT_SYSIO	2
+
+#define ATOM_UNIT_MICROSEC	0
+#define ATOM_UNIT_MILLISEC	1
+
+#define PLL_INDEX	2
+#define PLL_DATA	3
+
+typedef struct {
+	struct atom_context *ctx;
+
+	uint32_t *ps, *ws;
+	int ps_shift;
+	uint16_t start;
+} atom_exec_context;
+
+int atom_debug = 0;
+void atom_execute_table(struct atom_context *ctx, int index, uint32_t * params);
+
+static uint32_t atom_arg_mask[8] =
+    { 0xFFFFFFFF, 0xFFFF, 0xFFFF00, 0xFFFF0000, 0xFF, 0xFF00, 0xFF0000,
+0xFF000000 };
+static int atom_arg_shift[8] = { 0, 0, 8, 16, 0, 8, 16, 24 };
+
+static int atom_dst_to_src[8][4] = {
+	/* translate destination alignment field to the source alignment encoding */
+	{0, 0, 0, 0},
+	{1, 2, 3, 0},
+	{1, 2, 3, 0},
+	{1, 2, 3, 0},
+	{4, 5, 6, 7},
+	{4, 5, 6, 7},
+	{4, 5, 6, 7},
+	{4, 5, 6, 7},
+};
+static int atom_def_dst[8] = { 0, 0, 1, 2, 0, 1, 2, 3 };
+
+static int debug_depth = 0;
+#ifdef ATOM_DEBUG
+static void debug_print_spaces(int n)
+{
+	while (n--)
+		printk("   ");
+}
+
+#define DEBUG(...) do if (atom_debug) { printk(KERN_DEBUG __VA_ARGS__); } while (0)
+#define SDEBUG(...) do if (atom_debug) { printk(KERN_DEBUG); debug_print_spaces(debug_depth); printk(__VA_ARGS__); } while (0)
+#else
+#define DEBUG(...) do { } while (0)
+#define SDEBUG(...) do { } while (0)
+#endif
+
+static uint32_t atom_iio_execute(struct atom_context *ctx, int base,
+				 uint32_t index, uint32_t data)
+{
+	uint32_t temp = 0xCDCDCDCD;
+	while (1)
+		switch (CU8(base)) {
+		case ATOM_IIO_NOP:
+			base++;
+			break;
+		case ATOM_IIO_READ:
+			temp = ctx->card->reg_read(ctx->card, CU16(base + 1));
+			base += 3;
+			break;
+		case ATOM_IIO_WRITE:
+			ctx->card->reg_write(ctx->card, CU16(base + 1), temp);
+			base += 3;
+			break;
+		case ATOM_IIO_CLEAR:
+			temp &=
+			    ~((0xFFFFFFFF >> (32 - CU8(base + 1))) <<
+			      CU8(base + 2));
+			base += 3;
+			break;
+		case ATOM_IIO_SET:
+			temp |=
+			    (0xFFFFFFFF >> (32 - CU8(base + 1))) << CU8(base +
+									2);
+			base += 3;
+			break;
+		case ATOM_IIO_MOVE_INDEX:
+			temp &=
+			    ~((0xFFFFFFFF >> (32 - CU8(base + 1))) <<
+			      CU8(base + 2));
+			temp |=
+			    ((index >> CU8(base + 2)) &
+			     (0xFFFFFFFF >> (32 - CU8(base + 1)))) << CU8(base +
+									  3);
+			base += 4;
+			break;
+		case ATOM_IIO_MOVE_DATA:
+			temp &=
+			    ~((0xFFFFFFFF >> (32 - CU8(base + 1))) <<
+			      CU8(base + 2));
+			temp |=
+			    ((data >> CU8(base + 2)) &
+			     (0xFFFFFFFF >> (32 - CU8(base + 1)))) << CU8(base +
+									  3);
+			base += 4;
+			break;
+		case ATOM_IIO_MOVE_ATTR:
+			temp &=
+			    ~((0xFFFFFFFF >> (32 - CU8(base + 1))) <<
+			      CU8(base + 2));
+			temp |=
+			    ((ctx->
+			      io_attr >> CU8(base + 2)) & (0xFFFFFFFF >> (32 -
+									  CU8
+									  (base
+									   +
+									   1))))
+			    << CU8(base + 3);
+			base += 4;
+			break;
+		case ATOM_IIO_END:
+			return temp;
+		default:
+			printk(KERN_INFO "Unknown IIO opcode.\n");
+			return 0;
+		}
+}
+
+static uint32_t atom_get_src_int(atom_exec_context *ctx, uint8_t attr,
+				 int *ptr, uint32_t *saved, int print)
+{
+	uint32_t idx, val = 0xCDCDCDCD, align, arg;
+	struct atom_context *gctx = ctx->ctx;
+	arg = attr & 7;
+	align = (attr >> 3) & 7;
+	switch (arg) {
+	case ATOM_ARG_REG:
+		idx = U16(*ptr);
+		(*ptr) += 2;
+		if (print)
+			DEBUG("REG[0x%04X]", idx);
+		idx += gctx->reg_block;
+		switch (gctx->io_mode) {
+		case ATOM_IO_MM:
+			val = gctx->card->reg_read(gctx->card, idx);
+			break;
+		case ATOM_IO_PCI:
+			printk(KERN_INFO
+			       "PCI registers are not implemented.\n");
+			return 0;
+		case ATOM_IO_SYSIO:
+			printk(KERN_INFO
+			       "SYSIO registers are not implemented.\n");
+			return 0;
+		default:
+			if (!(gctx->io_mode & 0x80)) {
+				printk(KERN_INFO "Bad IO mode.\n");
+				return 0;
+			}
+			if (!gctx->iio[gctx->io_mode & 0x7F]) {
+				printk(KERN_INFO
+				       "Undefined indirect IO read method %d.\n",
+				       gctx->io_mode & 0x7F);
+				return 0;
+			}
+			val =
+			    atom_iio_execute(gctx,
+					     gctx->iio[gctx->io_mode & 0x7F],
+					     idx, 0);
+		}
+		break;
+	case ATOM_ARG_PS:
+		idx = U8(*ptr);
+		(*ptr)++;
+		val = le32_to_cpu(ctx->ps[idx]);
+		if (print)
+			DEBUG("PS[0x%02X,0x%04X]", idx, val);
+		break;
+	case ATOM_ARG_WS:
+		idx = U8(*ptr);
+		(*ptr)++;
+		if (print)
+			DEBUG("WS[0x%02X]", idx);
+		switch (idx) {
+		case ATOM_WS_QUOTIENT:
+			val = gctx->divmul[0];
+			break;
+		case ATOM_WS_REMAINDER:
+			val = gctx->divmul[1];
+			break;
+		case ATOM_WS_DATAPTR:
+			val = gctx->data_block;
+			break;
+		case ATOM_WS_SHIFT:
+			val = gctx->shift;
+			break;
+		case ATOM_WS_OR_MASK:
+			val = 1 << gctx->shift;
+			break;
+		case ATOM_WS_AND_MASK:
+			val = ~(1 << gctx->shift);
+			break;
+		case ATOM_WS_FB_WINDOW:
+			val = gctx->fb_base;
+			break;
+		case ATOM_WS_ATTRIBUTES:
+			val = gctx->io_attr;
+			break;
+		default:
+			val = ctx->ws[idx];
+		}
+		break;
+	case ATOM_ARG_ID:
+		idx = U16(*ptr);
+		(*ptr) += 2;
+		if (print) {
+			if (gctx->data_block)
+				DEBUG("ID[0x%04X+%04X]", idx, gctx->data_block);
+			else
+				DEBUG("ID[0x%04X]", idx);
+		}
+		val = U32(idx + gctx->data_block);
+		break;
+	case ATOM_ARG_FB:
+		idx = U8(*ptr);
+		(*ptr)++;
+		if (print)
+			DEBUG("FB[0x%02X]", idx);
+		printk(KERN_INFO "FB access is not implemented.\n");
+		return 0;
+	case ATOM_ARG_IMM:
+		switch (align) {
+		case ATOM_SRC_DWORD:
+			val = U32(*ptr);
+			(*ptr) += 4;
+			if (print)
+				DEBUG("IMM 0x%08X\n", val);
+			return val;
+		case ATOM_SRC_WORD0:
+		case ATOM_SRC_WORD8:
+		case ATOM_SRC_WORD16:
+			val = U16(*ptr);
+			(*ptr) += 2;
+			if (print)
+				DEBUG("IMM 0x%04X\n", val);
+			return val;
+		case ATOM_SRC_BYTE0:
+		case ATOM_SRC_BYTE8:
+		case ATOM_SRC_BYTE16:
+		case ATOM_SRC_BYTE24:
+			val = U8(*ptr);
+			(*ptr)++;
+			if (print)
+				DEBUG("IMM 0x%02X\n", val);
+			return val;
+		}
+		return 0;
+	case ATOM_ARG_PLL:
+		idx = U8(*ptr);
+		(*ptr)++;
+		if (print)
+			DEBUG("PLL[0x%02X]", idx);
+		val = gctx->card->pll_read(gctx->card, idx);
+		break;
+	case ATOM_ARG_MC:
+		idx = U8(*ptr);
+		(*ptr)++;
+		if (print)
+			DEBUG("MC[0x%02X]", idx);
+		val = gctx->card->mc_read(gctx->card, idx);
+		break;
+	}
+	if (saved)
+		*saved = val;
+	val &= atom_arg_mask[align];
+	val >>= atom_arg_shift[align];
+	if (print)
+		switch (align) {
+		case ATOM_SRC_DWORD:
+			DEBUG(".[31:0] -> 0x%08X\n", val);
+			break;
+		case ATOM_SRC_WORD0:
+			DEBUG(".[15:0] -> 0x%04X\n", val);
+			break;
+		case ATOM_SRC_WORD8:
+			DEBUG(".[23:8] -> 0x%04X\n", val);
+			break;
+		case ATOM_SRC_WORD16:
+			DEBUG(".[31:16] -> 0x%04X\n", val);
+			break;
+		case ATOM_SRC_BYTE0:
+			DEBUG(".[7:0] -> 0x%02X\n", val);
+			break;
+		case ATOM_SRC_BYTE8:
+			DEBUG(".[15:8] -> 0x%02X\n", val);
+			break;
+		case ATOM_SRC_BYTE16:
+			DEBUG(".[23:16] -> 0x%02X\n", val);
+			break;
+		case ATOM_SRC_BYTE24:
+			DEBUG(".[31:24] -> 0x%02X\n", val);
+			break;
+		}
+	return val;
+}
+
+static void atom_skip_src_int(atom_exec_context *ctx, uint8_t attr, int *ptr)
+{
+	uint32_t align = (attr >> 3) & 7, arg = attr & 7;
+	switch (arg) {
+	case ATOM_ARG_REG:
+	case ATOM_ARG_ID:
+		(*ptr) += 2;
+		break;
+	case ATOM_ARG_PLL:
+	case ATOM_ARG_MC:
+	case ATOM_ARG_PS:
+	case ATOM_ARG_WS:
+	case ATOM_ARG_FB:
+		(*ptr)++;
+		break;
+	case ATOM_ARG_IMM:
+		switch (align) {
+		case ATOM_SRC_DWORD:
+			(*ptr) += 4;
+			return;
+		case ATOM_SRC_WORD0:
+		case ATOM_SRC_WORD8:
+		case ATOM_SRC_WORD16:
+			(*ptr) += 2;
+			return;
+		case ATOM_SRC_BYTE0:
+		case ATOM_SRC_BYTE8:
+		case ATOM_SRC_BYTE16:
+		case ATOM_SRC_BYTE24:
+			(*ptr)++;
+			return;
+		}
+		return;
+	}
+}
+
+static uint32_t atom_get_src(atom_exec_context *ctx, uint8_t attr, int *ptr)
+{
+	return atom_get_src_int(ctx, attr, ptr, NULL, 1);
+}
+
+static uint32_t atom_get_dst(atom_exec_context *ctx, int arg, uint8_t attr,
+			     int *ptr, uint32_t *saved, int print)
+{
+	return atom_get_src_int(ctx,
+				arg | atom_dst_to_src[(attr >> 3) &
+						      7][(attr >> 6) & 3] << 3,
+				ptr, saved, print);
+}
+
+static void atom_skip_dst(atom_exec_context *ctx, int arg, uint8_t attr, int *ptr)
+{
+	atom_skip_src_int(ctx,
+			  arg | atom_dst_to_src[(attr >> 3) & 7][(attr >> 6) &
+								 3] << 3, ptr);
+}
+
+static void atom_put_dst(atom_exec_context *ctx, int arg, uint8_t attr,
+			 int *ptr, uint32_t val, uint32_t saved)
+{
+	uint32_t align =
+	    atom_dst_to_src[(attr >> 3) & 7][(attr >> 6) & 3], old_val =
+	    val, idx;
+	struct atom_context *gctx = ctx->ctx;
+	old_val &= atom_arg_mask[align] >> atom_arg_shift[align];
+	val <<= atom_arg_shift[align];
+	val &= atom_arg_mask[align];
+	saved &= ~atom_arg_mask[align];
+	val |= saved;
+	switch (arg) {
+	case ATOM_ARG_REG:
+		idx = U16(*ptr);
+		(*ptr) += 2;
+		DEBUG("REG[0x%04X]", idx);
+		idx += gctx->reg_block;
+		switch (gctx->io_mode) {
+		case ATOM_IO_MM:
+			if (idx == 0)
+				gctx->card->reg_write(gctx->card, idx,
+						      val << 2);
+			else
+				gctx->card->reg_write(gctx->card, idx, val);
+			break;
+		case ATOM_IO_PCI:
+			printk(KERN_INFO
+			       "PCI registers are not implemented.\n");
+			return;
+		case ATOM_IO_SYSIO:
+			printk(KERN_INFO
+			       "SYSIO registers are not implemented.\n");
+			return;
+		default:
+			if (!(gctx->io_mode & 0x80)) {
+				printk(KERN_INFO "Bad IO mode.\n");
+				return;
+			}
+			if (!gctx->iio[gctx->io_mode & 0xFF]) {
+				printk(KERN_INFO
+				       "Undefined indirect IO write method %d.\n",
+				       gctx->io_mode & 0x7F);
+				return;
+			}
+			atom_iio_execute(gctx, gctx->iio[gctx->io_mode & 0xFF],
+					 idx, val);
+		}
+		break;
+	case ATOM_ARG_PS:
+		idx = U8(*ptr);
+		(*ptr)++;
+		DEBUG("PS[0x%02X]", idx);
+		ctx->ps[idx] = cpu_to_le32(val);
+		break;
+	case ATOM_ARG_WS:
+		idx = U8(*ptr);
+		(*ptr)++;
+		DEBUG("WS[0x%02X]", idx);
+		switch (idx) {
+		case ATOM_WS_QUOTIENT:
+			gctx->divmul[0] = val;
+			break;
+		case ATOM_WS_REMAINDER:
+			gctx->divmul[1] = val;
+			break;
+		case ATOM_WS_DATAPTR:
+			gctx->data_block = val;
+			break;
+		case ATOM_WS_SHIFT:
+			gctx->shift = val;
+			break;
+		case ATOM_WS_OR_MASK:
+		case ATOM_WS_AND_MASK:
+			break;
+		case ATOM_WS_FB_WINDOW:
+			gctx->fb_base = val;
+			break;
+		case ATOM_WS_ATTRIBUTES:
+			gctx->io_attr = val;
+			break;
+		default:
+			ctx->ws[idx] = val;
+		}
+		break;
+	case ATOM_ARG_FB:
+		idx = U8(*ptr);
+		(*ptr)++;
+		DEBUG("FB[0x%02X]", idx);
+		printk(KERN_INFO "FB access is not implemented.\n");
+		return;
+	case ATOM_ARG_PLL:
+		idx = U8(*ptr);
+		(*ptr)++;
+		DEBUG("PLL[0x%02X]", idx);
+		gctx->card->pll_write(gctx->card, idx, val);
+		break;
+	case ATOM_ARG_MC:
+		idx = U8(*ptr);
+		(*ptr)++;
+		DEBUG("MC[0x%02X]", idx);
+		gctx->card->mc_write(gctx->card, idx, val);
+		return;
+	}
+	switch (align) {
+	case ATOM_SRC_DWORD:
+		DEBUG(".[31:0] <- 0x%08X\n", old_val);
+		break;
+	case ATOM_SRC_WORD0:
+		DEBUG(".[15:0] <- 0x%04X\n", old_val);
+		break;
+	case ATOM_SRC_WORD8:
+		DEBUG(".[23:8] <- 0x%04X\n", old_val);
+		break;
+	case ATOM_SRC_WORD16:
+		DEBUG(".[31:16] <- 0x%04X\n", old_val);
+		break;
+	case ATOM_SRC_BYTE0:
+		DEBUG(".[7:0] <- 0x%02X\n", old_val);
+		break;
+	case ATOM_SRC_BYTE8:
+		DEBUG(".[15:8] <- 0x%02X\n", old_val);
+		break;
+	case ATOM_SRC_BYTE16:
+		DEBUG(".[23:16] <- 0x%02X\n", old_val);
+		break;
+	case ATOM_SRC_BYTE24:
+		DEBUG(".[31:24] <- 0x%02X\n", old_val);
+		break;
+	}
+}
+
+static void atom_op_add(atom_exec_context *ctx, int *ptr, int arg)
+{
+	uint8_t attr = U8((*ptr)++);
+	uint32_t dst, src, saved;
+	int dptr = *ptr;
+	SDEBUG("   dst: ");
+	dst = atom_get_dst(ctx, arg, attr, ptr, &saved, 1);
+	SDEBUG("   src: ");
+	src = atom_get_src(ctx, attr, ptr);
+	dst += src;
+	SDEBUG("   dst: ");
+	atom_put_dst(ctx, arg, attr, &dptr, dst, saved);
+}
+
+static void atom_op_and(atom_exec_context *ctx, int *ptr, int arg)
+{
+	uint8_t attr = U8((*ptr)++);
+	uint32_t dst, src, saved;
+	int dptr = *ptr;
+	SDEBUG("   dst: ");
+	dst = atom_get_dst(ctx, arg, attr, ptr, &saved, 1);
+	SDEBUG("   src: ");
+	src = atom_get_src(ctx, attr, ptr);
+	dst &= src;
+	SDEBUG("   dst: ");
+	atom_put_dst(ctx, arg, attr, &dptr, dst, saved);
+}
+
+static void atom_op_beep(atom_exec_context *ctx, int *ptr, int arg)
+{
+	printk("ATOM BIOS beeped!\n");
+}
+
+static void atom_op_calltable(atom_exec_context *ctx, int *ptr, int arg)
+{
+	int idx = U8((*ptr)++);
+	if (idx < ATOM_TABLE_NAMES_CNT)
+		SDEBUG("   table: %d (%s)\n", idx, atom_table_names[idx]);
+	else
+		SDEBUG("   table: %d\n", idx);
+	if (U16(ctx->ctx->cmd_table + 4 + 2 * idx))
+		atom_execute_table(ctx->ctx, idx, ctx->ps + ctx->ps_shift);
+}
+
+static void atom_op_clear(atom_exec_context *ctx, int *ptr, int arg)
+{
+	uint8_t attr = U8((*ptr)++);
+	uint32_t saved;
+	int dptr = *ptr;
+	attr &= 0x38;
+	attr |= atom_def_dst[attr >> 3] << 6;
+	atom_get_dst(ctx, arg, attr, ptr, &saved, 0);
+	SDEBUG("   dst: ");
+	atom_put_dst(ctx, arg, attr, &dptr, 0, saved);
+}
+
+static void atom_op_compare(atom_exec_context *ctx, int *ptr, int arg)
+{
+	uint8_t attr = U8((*ptr)++);
+	uint32_t dst, src;
+	SDEBUG("   src1: ");
+	dst = atom_get_dst(ctx, arg, attr, ptr, NULL, 1);
+	SDEBUG("   src2: ");
+	src = atom_get_src(ctx, attr, ptr);
+	ctx->ctx->cs_equal = (dst == src);
+	ctx->ctx->cs_above = (dst > src);
+	SDEBUG("   result: %s %s\n", ctx->ctx->cs_equal ? "EQ" : "NE",
+	       ctx->ctx->cs_above ? "GT" : "LE");
+}
+
+static void atom_op_delay(atom_exec_context *ctx, int *ptr, int arg)
+{
+	uint8_t count = U8((*ptr)++);
+	SDEBUG("   count: %d\n", count);
+	if (arg == ATOM_UNIT_MICROSEC)
+		schedule_timeout_uninterruptible(usecs_to_jiffies(count));
+	else
+		schedule_timeout_uninterruptible(msecs_to_jiffies(count));
+}
+
+static void atom_op_div(atom_exec_context *ctx, int *ptr, int arg)
+{
+	uint8_t attr = U8((*ptr)++);
+	uint32_t dst, src;
+	SDEBUG("   src1: ");
+	dst = atom_get_dst(ctx, arg, attr, ptr, NULL, 1);
+	SDEBUG("   src2: ");
+	src = atom_get_src(ctx, attr, ptr);
+	if (src != 0) {
+		ctx->ctx->divmul[0] = dst / src;
+		ctx->ctx->divmul[1] = dst % src;
+	} else {
+		ctx->ctx->divmul[0] = 0;
+		ctx->ctx->divmul[1] = 0;
+	}
+}
+
+static void atom_op_eot(atom_exec_context *ctx, int *ptr, int arg)
+{
+	/* functionally, a nop */
+}
+
+static void atom_op_jump(atom_exec_context *ctx, int *ptr, int arg)
+{
+	int execute = 0, target = U16(*ptr);
+	(*ptr) += 2;
+	switch (arg) {
+	case ATOM_COND_ABOVE:
+		execute = ctx->ctx->cs_above;
+		break;
+	case ATOM_COND_ABOVEOREQUAL:
+		execute = ctx->ctx->cs_above || ctx->ctx->cs_equal;
+		break;
+	case ATOM_COND_ALWAYS:
+		execute = 1;
+		break;
+	case ATOM_COND_BELOW:
+		execute = !(ctx->ctx->cs_above || ctx->ctx->cs_equal);
+		break;
+	case ATOM_COND_BELOWOREQUAL:
+		execute = !ctx->ctx->cs_above;
+		break;
+	case ATOM_COND_EQUAL:
+		execute = ctx->ctx->cs_equal;
+		break;
+	case ATOM_COND_NOTEQUAL:
+		execute = !ctx->ctx->cs_equal;
+		break;
+	}
+	if (arg != ATOM_COND_ALWAYS)
+		SDEBUG("   taken: %s\n", execute ? "yes" : "no");
+	SDEBUG("   target: 0x%04X\n", target);
+	if (execute)
+		*ptr = ctx->start + target;
+}
+
+static void atom_op_mask(atom_exec_context *ctx, int *ptr, int arg)
+{
+	uint8_t attr = U8((*ptr)++);
+	uint32_t dst, src1, src2, saved;
+	int dptr = *ptr;
+	SDEBUG("   dst: ");
+	dst = atom_get_dst(ctx, arg, attr, ptr, &saved, 1);
+	SDEBUG("   src1: ");
+	src1 = atom_get_src(ctx, attr, ptr);
+	SDEBUG("   src2: ");
+	src2 = atom_get_src(ctx, attr, ptr);
+	dst &= src1;
+	dst |= src2;
+	SDEBUG("   dst: ");
+	atom_put_dst(ctx, arg, attr, &dptr, dst, saved);
+}
+
+static void atom_op_move(atom_exec_context *ctx, int *ptr, int arg)
+{
+	uint8_t attr = U8((*ptr)++);
+	uint32_t src, saved;
+	int dptr = *ptr;
+	if (((attr >> 3) & 7) != ATOM_SRC_DWORD)
+		atom_get_dst(ctx, arg, attr, ptr, &saved, 0);
+	else {
+		atom_skip_dst(ctx, arg, attr, ptr);
+		saved = 0xCDCDCDCD;
+	}
+	SDEBUG("   src: ");
+	src = atom_get_src(ctx, attr, ptr);
+	SDEBUG("   dst: ");
+	atom_put_dst(ctx, arg, attr, &dptr, src, saved);
+}
+
+static void atom_op_mul(atom_exec_context *ctx, int *ptr, int arg)
+{
+	uint8_t attr = U8((*ptr)++);
+	uint32_t dst, src;
+	SDEBUG("   src1: ");
+	dst = atom_get_dst(ctx, arg, attr, ptr, NULL, 1);
+	SDEBUG("   src2: ");
+	src = atom_get_src(ctx, attr, ptr);
+	ctx->ctx->divmul[0] = dst * src;
+}
+
+static void atom_op_nop(atom_exec_context *ctx, int *ptr, int arg)
+{
+	/* nothing */
+}
+
+static void atom_op_or(atom_exec_context *ctx, int *ptr, int arg)
+{
+	uint8_t attr = U8((*ptr)++);
+	uint32_t dst, src, saved;
+	int dptr = *ptr;
+	SDEBUG("   dst: ");
+	dst = atom_get_dst(ctx, arg, attr, ptr, &saved, 1);
+	SDEBUG("   src: ");
+	src = atom_get_src(ctx, attr, ptr);
+	dst |= src;
+	SDEBUG("   dst: ");
+	atom_put_dst(ctx, arg, attr, &dptr, dst, saved);
+}
+
+static void atom_op_postcard(atom_exec_context *ctx, int *ptr, int arg)
+{
+	uint8_t val = U8((*ptr)++);
+	SDEBUG("POST card output: 0x%02X\n", val);
+}
+
+static void atom_op_repeat(atom_exec_context *ctx, int *ptr, int arg)
+{
+	printk(KERN_INFO "unimplemented!\n");
+}
+
+static void atom_op_restorereg(atom_exec_context *ctx, int *ptr, int arg)
+{
+	printk(KERN_INFO "unimplemented!\n");
+}
+
+static void atom_op_savereg(atom_exec_context *ctx, int *ptr, int arg)
+{
+	printk(KERN_INFO "unimplemented!\n");
+}
+
+static void atom_op_setdatablock(atom_exec_context *ctx, int *ptr, int arg)
+{
+	int idx = U8(*ptr);
+	(*ptr)++;
+	SDEBUG("   block: %d\n", idx);
+	if (!idx)
+		ctx->ctx->data_block = 0;
+	else if (idx == 255)
+		ctx->ctx->data_block = ctx->start;
+	else
+		ctx->ctx->data_block = U16(ctx->ctx->data_table + 4 + 2 * idx);
+	SDEBUG("   base: 0x%04X\n", ctx->ctx->data_block);
+}
+
+static void atom_op_setfbbase(atom_exec_context *ctx, int *ptr, int arg)
+{
+	uint8_t attr = U8((*ptr)++);
+	SDEBUG("   fb_base: ");
+	ctx->ctx->fb_base = atom_get_src(ctx, attr, ptr);
+}
+
+static void atom_op_setport(atom_exec_context *ctx, int *ptr, int arg)
+{
+	int port;
+	switch (arg) {
+	case ATOM_PORT_ATI:
+		port = U16(*ptr);
+		if (port < ATOM_IO_NAMES_CNT)
+			SDEBUG("   port: %d (%s)\n", port, atom_io_names[port]);
+		else
+			SDEBUG("   port: %d\n", port);
+		if (!port)
+			ctx->ctx->io_mode = ATOM_IO_MM;
+		else
+			ctx->ctx->io_mode = ATOM_IO_IIO | port;
+		(*ptr) += 2;
+		break;
+	case ATOM_PORT_PCI:
+		ctx->ctx->io_mode = ATOM_IO_PCI;
+		(*ptr)++;
+		break;
+	case ATOM_PORT_SYSIO:
+		ctx->ctx->io_mode = ATOM_IO_SYSIO;
+		(*ptr)++;
+		break;
+	}
+}
+
+static void atom_op_setregblock(atom_exec_context *ctx, int *ptr, int arg)
+{
+	ctx->ctx->reg_block = U16(*ptr);
+	(*ptr) += 2;
+	SDEBUG("   base: 0x%04X\n", ctx->ctx->reg_block);
+}
+
+static void atom_op_shl(atom_exec_context *ctx, int *ptr, int arg)
+{
+	uint8_t attr = U8((*ptr)++), shift;
+	uint32_t saved, dst;
+	int dptr = *ptr;
+	attr &= 0x38;
+	attr |= atom_def_dst[attr >> 3] << 6;
+	SDEBUG("   dst: ");
+	dst = atom_get_dst(ctx, arg, attr, ptr, &saved, 1);
+	shift = U8((*ptr)++);
+	SDEBUG("   shift: %d\n", shift);
+	dst <<= shift;
+	SDEBUG("   dst: ");
+	atom_put_dst(ctx, arg, attr, &dptr, dst, saved);
+}
+
+static void atom_op_shr(atom_exec_context *ctx, int *ptr, int arg)
+{
+	uint8_t attr = U8((*ptr)++), shift;
+	uint32_t saved, dst;
+	int dptr = *ptr;
+	attr &= 0x38;
+	attr |= atom_def_dst[attr >> 3] << 6;
+	SDEBUG("   dst: ");
+	dst = atom_get_dst(ctx, arg, attr, ptr, &saved, 1);
+	shift = U8((*ptr)++);
+	SDEBUG("   shift: %d\n", shift);
+	dst >>= shift;
+	SDEBUG("   dst: ");
+	atom_put_dst(ctx, arg, attr, &dptr, dst, saved);
+}
+
+static void atom_op_sub(atom_exec_context *ctx, int *ptr, int arg)
+{
+	uint8_t attr = U8((*ptr)++);
+	uint32_t dst, src, saved;
+	int dptr = *ptr;
+	SDEBUG("   dst: ");
+	dst = atom_get_dst(ctx, arg, attr, ptr, &saved, 1);
+	SDEBUG("   src: ");
+	src = atom_get_src(ctx, attr, ptr);
+	dst -= src;
+	SDEBUG("   dst: ");
+	atom_put_dst(ctx, arg, attr, &dptr, dst, saved);
+}
+
+static void atom_op_switch(atom_exec_context *ctx, int *ptr, int arg)
+{
+	uint8_t attr = U8((*ptr)++);
+	uint32_t src, val, target;
+	SDEBUG("   switch: ");
+	src = atom_get_src(ctx, attr, ptr);
+	while (U16(*ptr) != ATOM_CASE_END)
+		if (U8(*ptr) == ATOM_CASE_MAGIC) {
+			(*ptr)++;
+			SDEBUG("   case: ");
+			val =
+			    atom_get_src(ctx, (attr & 0x38) | ATOM_ARG_IMM,
+					 ptr);
+			target = U16(*ptr);
+			if (val == src) {
+				SDEBUG("   target: %04X\n", target);
+				*ptr = ctx->start + target;
+				return;
+			}
+			(*ptr) += 2;
+		} else {
+			printk(KERN_INFO "Bad case.\n");
+			return;
+		}
+	(*ptr) += 2;
+}
+
+static void atom_op_test(atom_exec_context *ctx, int *ptr, int arg)
+{
+	uint8_t attr = U8((*ptr)++);
+	uint32_t dst, src;
+	SDEBUG("   src1: ");
+	dst = atom_get_dst(ctx, arg, attr, ptr, NULL, 1);
+	SDEBUG("   src2: ");
+	src = atom_get_src(ctx, attr, ptr);
+	ctx->ctx->cs_equal = ((dst & src) == 0);
+	SDEBUG("   result: %s\n", ctx->ctx->cs_equal ? "EQ" : "NE");
+}
+
+static void atom_op_xor(atom_exec_context *ctx, int *ptr, int arg)
+{
+	uint8_t attr = U8((*ptr)++);
+	uint32_t dst, src, saved;
+	int dptr = *ptr;
+	SDEBUG("   dst: ");
+	dst = atom_get_dst(ctx, arg, attr, ptr, &saved, 1);
+	SDEBUG("   src: ");
+	src = atom_get_src(ctx, attr, ptr);
+	dst ^= src;
+	SDEBUG("   dst: ");
+	atom_put_dst(ctx, arg, attr, &dptr, dst, saved);
+}
+
+static void atom_op_debug(atom_exec_context *ctx, int *ptr, int arg)
+{
+	printk(KERN_INFO "unimplemented!\n");
+}
+
+static struct {
+	void (*func) (atom_exec_context *, int *, int);
+	int arg;
+} opcode_table[ATOM_OP_CNT] = {
+	{
+	NULL, 0}, {
+	atom_op_move, ATOM_ARG_REG}, {
+	atom_op_move, ATOM_ARG_PS}, {
+	atom_op_move, ATOM_ARG_WS}, {
+	atom_op_move, ATOM_ARG_FB}, {
+	atom_op_move, ATOM_ARG_PLL}, {
+	atom_op_move, ATOM_ARG_MC}, {
+	atom_op_and, ATOM_ARG_REG}, {
+	atom_op_and, ATOM_ARG_PS}, {
+	atom_op_and, ATOM_ARG_WS}, {
+	atom_op_and, ATOM_ARG_FB}, {
+	atom_op_and, ATOM_ARG_PLL}, {
+	atom_op_and, ATOM_ARG_MC}, {
+	atom_op_or, ATOM_ARG_REG}, {
+	atom_op_or, ATOM_ARG_PS}, {
+	atom_op_or, ATOM_ARG_WS}, {
+	atom_op_or, ATOM_ARG_FB}, {
+	atom_op_or, ATOM_ARG_PLL}, {
+	atom_op_or, ATOM_ARG_MC}, {
+	atom_op_shl, ATOM_ARG_REG}, {
+	atom_op_shl, ATOM_ARG_PS}, {
+	atom_op_shl, ATOM_ARG_WS}, {
+	atom_op_shl, ATOM_ARG_FB}, {
+	atom_op_shl, ATOM_ARG_PLL}, {
+	atom_op_shl, ATOM_ARG_MC}, {
+	atom_op_shr, ATOM_ARG_REG}, {
+	atom_op_shr, ATOM_ARG_PS}, {
+	atom_op_shr, ATOM_ARG_WS}, {
+	atom_op_shr, ATOM_ARG_FB}, {
+	atom_op_shr, ATOM_ARG_PLL}, {
+	atom_op_shr, ATOM_ARG_MC}, {
+	atom_op_mul, ATOM_ARG_REG}, {
+	atom_op_mul, ATOM_ARG_PS}, {
+	atom_op_mul, ATOM_ARG_WS}, {
+	atom_op_mul, ATOM_ARG_FB}, {
+	atom_op_mul, ATOM_ARG_PLL}, {
+	atom_op_mul, ATOM_ARG_MC}, {
+	atom_op_div, ATOM_ARG_REG}, {
+	atom_op_div, ATOM_ARG_PS}, {
+	atom_op_div, ATOM_ARG_WS}, {
+	atom_op_div, ATOM_ARG_FB}, {
+	atom_op_div, ATOM_ARG_PLL}, {
+	atom_op_div, ATOM_ARG_MC}, {
+	atom_op_add, ATOM_ARG_REG}, {
+	atom_op_add, ATOM_ARG_PS}, {
+	atom_op_add, ATOM_ARG_WS}, {
+	atom_op_add, ATOM_ARG_FB}, {
+	atom_op_add, ATOM_ARG_PLL}, {
+	atom_op_add, ATOM_ARG_MC}, {
+	atom_op_sub, ATOM_ARG_REG}, {
+	atom_op_sub, ATOM_ARG_PS}, {
+	atom_op_sub, ATOM_ARG_WS}, {
+	atom_op_sub, ATOM_ARG_FB}, {
+	atom_op_sub, ATOM_ARG_PLL}, {
+	atom_op_sub, ATOM_ARG_MC}, {
+	atom_op_setport, ATOM_PORT_ATI}, {
+	atom_op_setport, ATOM_PORT_PCI}, {
+	atom_op_setport, ATOM_PORT_SYSIO}, {
+	atom_op_setregblock, 0}, {
+	atom_op_setfbbase, 0}, {
+	atom_op_compare, ATOM_ARG_REG}, {
+	atom_op_compare, ATOM_ARG_PS}, {
+	atom_op_compare, ATOM_ARG_WS}, {
+	atom_op_compare, ATOM_ARG_FB}, {
+	atom_op_compare, ATOM_ARG_PLL}, {
+	atom_op_compare, ATOM_ARG_MC}, {
+	atom_op_switch, 0}, {
+	atom_op_jump, ATOM_COND_ALWAYS}, {
+	atom_op_jump, ATOM_COND_EQUAL}, {
+	atom_op_jump, ATOM_COND_BELOW}, {
+	atom_op_jump, ATOM_COND_ABOVE}, {
+	atom_op_jump, ATOM_COND_BELOWOREQUAL}, {
+	atom_op_jump, ATOM_COND_ABOVEOREQUAL}, {
+	atom_op_jump, ATOM_COND_NOTEQUAL}, {
+	atom_op_test, ATOM_ARG_REG}, {
+	atom_op_test, ATOM_ARG_PS}, {
+	atom_op_test, ATOM_ARG_WS}, {
+	atom_op_test, ATOM_ARG_FB}, {
+	atom_op_test, ATOM_ARG_PLL}, {
+	atom_op_test, ATOM_ARG_MC}, {
+	atom_op_delay, ATOM_UNIT_MILLISEC}, {
+	atom_op_delay, ATOM_UNIT_MICROSEC}, {
+	atom_op_calltable, 0}, {
+	atom_op_repeat, 0}, {
+	atom_op_clear, ATOM_ARG_REG}, {
+	atom_op_clear, ATOM_ARG_PS}, {
+	atom_op_clear, ATOM_ARG_WS}, {
+	atom_op_clear, ATOM_ARG_FB}, {
+	atom_op_clear, ATOM_ARG_PLL}, {
+	atom_op_clear, ATOM_ARG_MC}, {
+	atom_op_nop, 0}, {
+	atom_op_eot, 0}, {
+	atom_op_mask, ATOM_ARG_REG}, {
+	atom_op_mask, ATOM_ARG_PS}, {
+	atom_op_mask, ATOM_ARG_WS}, {
+	atom_op_mask, ATOM_ARG_FB}, {
+	atom_op_mask, ATOM_ARG_PLL}, {
+	atom_op_mask, ATOM_ARG_MC}, {
+	atom_op_postcard, 0}, {
+	atom_op_beep, 0}, {
+	atom_op_savereg, 0}, {
+	atom_op_restorereg, 0}, {
+	atom_op_setdatablock, 0}, {
+	atom_op_xor, ATOM_ARG_REG}, {
+	atom_op_xor, ATOM_ARG_PS}, {
+	atom_op_xor, ATOM_ARG_WS}, {
+	atom_op_xor, ATOM_ARG_FB}, {
+	atom_op_xor, ATOM_ARG_PLL}, {
+	atom_op_xor, ATOM_ARG_MC}, {
+	atom_op_shl, ATOM_ARG_REG}, {
+	atom_op_shl, ATOM_ARG_PS}, {
+	atom_op_shl, ATOM_ARG_WS}, {
+	atom_op_shl, ATOM_ARG_FB}, {
+	atom_op_shl, ATOM_ARG_PLL}, {
+	atom_op_shl, ATOM_ARG_MC}, {
+	atom_op_shr, ATOM_ARG_REG}, {
+	atom_op_shr, ATOM_ARG_PS}, {
+	atom_op_shr, ATOM_ARG_WS}, {
+	atom_op_shr, ATOM_ARG_FB}, {
+	atom_op_shr, ATOM_ARG_PLL}, {
+	atom_op_shr, ATOM_ARG_MC}, {
+atom_op_debug, 0},};
+
+void atom_execute_table(struct atom_context *ctx, int index, uint32_t * params)
+{
+	int base = CU16(ctx->cmd_table + 4 + 2 * index);
+	int len, ws, ps, ptr;
+	unsigned char op;
+	atom_exec_context ectx;
+
+	if (!base)
+		return;
+
+	len = CU16(base + ATOM_CT_SIZE_PTR);
+	ws = CU8(base + ATOM_CT_WS_PTR);
+	ps = CU8(base + ATOM_CT_PS_PTR) & ATOM_CT_PS_MASK;
+	ptr = base + ATOM_CT_CODE_PTR;
+
+	SDEBUG(">> execute %04X (len %d, WS %d, PS %d)\n", base, len, ws, ps);
+
+	/* reset reg block */
+	ctx->reg_block = 0;
+	ectx.ctx = ctx;
+	ectx.ps_shift = ps / 4;
+	ectx.start = base;
+	ectx.ps = params;
+	if (ws)
+		ectx.ws = kzalloc(4 * ws, GFP_KERNEL);
+	else
+		ectx.ws = NULL;
+
+	debug_depth++;
+	while (1) {
+		op = CU8(ptr++);
+		if (op < ATOM_OP_NAMES_CNT)
+			SDEBUG("%s @ 0x%04X\n", atom_op_names[op], ptr - 1);
+		else
+			SDEBUG("[%d] @ 0x%04X\n", op, ptr - 1);
+
+		if (op < ATOM_OP_CNT && op > 0)
+			opcode_table[op].func(&ectx, &ptr,
+					      opcode_table[op].arg);
+		else
+			break;
+
+		if (op == ATOM_OP_EOT)
+			break;
+	}
+	debug_depth--;
+	SDEBUG("<<\n");
+
+	if (ws)
+		kfree(ectx.ws);
+}
+
+static int atom_iio_len[] = { 1, 2, 3, 3, 3, 3, 4, 4, 4, 3 };
+
+static void atom_index_iio(struct atom_context *ctx, int base)
+{
+	ctx->iio = kzalloc(2 * 256, GFP_KERNEL);
+	while (CU8(base) == ATOM_IIO_START) {
+		ctx->iio[CU8(base + 1)] = base + 2;
+		base += 2;
+		while (CU8(base) != ATOM_IIO_END)
+			base += atom_iio_len[CU8(base)];
+		base += 3;
+	}
+}
+
+struct atom_context *atom_parse(struct card_info *card, void *bios)
+{
+	int base;
+	struct atom_context *ctx =
+	    kzalloc(sizeof(struct atom_context), GFP_KERNEL);
+	char *str;
+	char name[512];
+	int i;
+
+	ctx->card = card;
+	ctx->bios = bios;
+
+	if (CU16(0) != ATOM_BIOS_MAGIC) {
+		printk(KERN_INFO "Invalid BIOS magic.\n");
+		kfree(ctx);
+		return NULL;
+	}
+	if (strncmp
+	    (CSTR(ATOM_ATI_MAGIC_PTR), ATOM_ATI_MAGIC,
+	     strlen(ATOM_ATI_MAGIC))) {
+		printk(KERN_INFO "Invalid ATI magic.\n");
+		kfree(ctx);
+		return NULL;
+	}
+
+	base = CU16(ATOM_ROM_TABLE_PTR);
+	if (strncmp
+	    (CSTR(base + ATOM_ROM_MAGIC_PTR), ATOM_ROM_MAGIC,
+	     strlen(ATOM_ROM_MAGIC))) {
+		printk(KERN_INFO "Invalid ATOM magic.\n");
+		kfree(ctx);
+		return NULL;
+	}
+
+	ctx->cmd_table = CU16(base + ATOM_ROM_CMD_PTR);
+	ctx->data_table = CU16(base + ATOM_ROM_DATA_PTR);
+	atom_index_iio(ctx, CU16(ctx->data_table + ATOM_DATA_IIO_PTR) + 4);
+
+	str = CSTR(CU16(base + ATOM_ROM_MSG_PTR));
+	while (*str && ((*str == '\n') || (*str == '\r')))
+		str++;
+	/* name string isn't always 0 terminated */
+	for (i = 0; i < 511; i++) {
+		name[i] = str[i];
+		if (name[i] < '.' || name[i] > 'z') {
+			name[i] = 0;
+			break;
+		}
+	}
+	printk(KERN_INFO "ATOM BIOS: %s\n", name);
+
+	return ctx;
+}
+
+int atom_asic_init(struct atom_context *ctx)
+{
+	int hwi = CU16(ctx->data_table + ATOM_DATA_FWI_PTR);
+	uint32_t ps[16];
+	memset(ps, 0, 64);
+
+	ps[0] = cpu_to_le32(CU32(hwi + ATOM_FWI_DEFSCLK_PTR));
+	ps[1] = cpu_to_le32(CU32(hwi + ATOM_FWI_DEFMCLK_PTR));
+	if (!ps[0] || !ps[1])
+		return 1;
+
+	if (!CU16(ctx->cmd_table + 4 + 2 * ATOM_CMD_INIT))
+		return 1;
+	atom_execute_table(ctx, ATOM_CMD_INIT, ps);
+
+	return 0;
+}
+
+void atom_destroy(struct atom_context *ctx)
+{
+	if (ctx->iio)
+		kfree(ctx->iio);
+	kfree(ctx);
+}
+
+void atom_parse_data_header(struct atom_context *ctx, int index,
+			    uint16_t * size, uint8_t * frev, uint8_t * crev,
+			    uint16_t * data_start)
+{
+	int offset = index * 2 + 4;
+	int idx = CU16(ctx->data_table + offset);
+
+	if (size)
+		*size = CU16(idx);
+	if (frev)
+		*frev = CU8(idx + 2);
+	if (crev)
+		*crev = CU8(idx + 3);
+	*data_start = idx;
+	return;
+}
+
+void atom_parse_cmd_header(struct atom_context *ctx, int index, uint8_t * frev,
+			   uint8_t * crev)
+{
+	int offset = index * 2 + 4;
+	int idx = CU16(ctx->cmd_table + offset);
+
+	if (frev)
+		*frev = CU8(idx + 2);
+	if (crev)
+		*crev = CU8(idx + 3);
+	return;
+}