Merge tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Don't destroy user event fields when removal fails

   User event fields are destroyed before the event is removed from
   visibility. But that can fail leaving the still visible event with no
   fields. Move the destroying of the fields to after the event is
   successfully removed from visibility.

 - Initialize function graph state is fork before calling
   copy_exec_state()

   For non-CLONE_VM forks, copy_exec_state() allocates a new
   task_exec_state. If that allocation fails, ftrace_graph_exit_task()
   will free the tasks ret_stack pointer. Since that pointer is still
   using the parent's ret_stack, it mistakenly frees the parent's
   pointer too.

   Call ftrace_graph_init() on the task first which will NULL out the
   new tasks's ret_stack and if the copy fails, it will not free
   anything.

 - Remove FGRAPH_MAX_INDEX

   The macro FGRAPH_MAX_INDEX was added but never used. Remove it.

 - Save ent_size in function graph printing of nested functions

   The function graph tracer needs to look at the next event to see if
   the next event is the return of the current function entry. If it is,
   it prints a single line:

	ktime_get();

   Otherwise it prints it like a nested function:

	tick_nohz_irq_exit() {
	    ktime_get();
	    kcpustat_irq_exit();
	}

   In order to look at the next event, it must save the current event so
   that it has the information to print from it. It saves the event in
   the iterator descriptor called "ent". What it doesn't save is the
   ent_size of the event which is now used to know if the function graph
   arguments are to be printed. The peek doesn't save the size so the
   size used happens to be that of the size of the last event that was
   seen.

   Save the entry event size in the iterator descriptor so that the
   correct size is used.

 - Fix several errors with freeing data in the histogram code

   The histogram code had a lot of leaked or or incorrect accounting
   when failures happen. Correct them.

 - Fix histogram regression of .percent and .graph modifiers

   Up until 6.3 histogram values could have "percent" or "graph"
   modifiers that changed how they were printed. But a change that added
   restricting histograms values from being strings, stack traces and
   other modifiers inadvertently prevented them from using the percent
   and graph modifiers, which were legal use cases for values.

   Put back the percent and graph modifiers.

 - Fix various typos in the comments

 - Set the trace_clock before initializing a histogram with clock
   argument

   The histogram API allows the user to specific which trace clock to
   use via a "clock=" string. The histogram is set up first before the
   clock is checked. If the passed in clock is not valid, it exits
   without fully fixing up the histogram leaving it on the list and a
   use-after-free can trigger.

   Update the clock argument first and if it fails then exit gracefully
   before the histogram trigger is placed on any lists.

 - Restore :mod: trailer after parsing in ftrace_set_clr_event

   The function ftrace_set_clr_event() modifies the parse string and
   needs to put it back to what was passed in. It searches for ":mod:"
   via a strsep() but fails to put back the first ':' in the string.

   Add back the ':' in the passed in string.

 - Take trace_array reference when opening a tracer options file

   The options files are dynamically created and some tracers add their
   own options. When a tracer adds their own list of options, the
   trace_array holding them has an array to hold the list of options for
   each tracer. This array increases in size via a krealloc(), and the
   new entry gets a newly allocated array to hold the options of the new
   tracer being added.

   The element in each entry of the tracer's option array holds a
   pointer back to the trace_array, a pointer to the tracer it is
   associated to, a pointer to the flags of the option.

   The issue is that these arrays are freed when the trace_array is
   freed when its instance it represents is removed from the instances
   directory. There's a race that an open of one of these options files
   can happen when the instance is being removed.

   Add a new helper function to be called by the open function of the
   options file to iterate all existing trace_arrays under a lock and
   find the one that has the given option element in one of it's tracer
   arrays. If found, then update the associated trace_array's reference
   counter to keep it from being freed. If not found, have the open call
   return -ENODEV.

 - Disable interrupts when acquiring the lock in rb_wake_up_waiters()

   The function rb_wake_up_waiters() assumes it will be called in
   interrupt context and does not disable irqs when taking
   cpu_buffer->reader_lock, which can be called in hard interrupt
   context. The issue is in PREEMPT_RT, this function is called in
   thread context leaving this lock open to a deadlock.

   Take the lock with interrupts disabled.

 - Use rcu_assign_pointer() for tmp_ops filter hash

   The tmp_ops used in update_ftrace_direct_mod() assigns its
   filter_hash field directly, but that field is annotated as __rcu and
   sparse complains. Assign it with rcu_assign_pointer()

 - Fix use-after-free in enable_trigger_private_data_free()

   The trace_event_call is accessed through the event_trigger_data's
   trace_event_file pointer to put the trace_event_call on freeing. The
   issue is that the trace_event_file data may have been freed already
   causing a use-after-free. Add a field to the event_trigger_data that
   points directly to the trace_event_call so that it can decrement its
   reference directly without needing to go through the
   trace_event_file.

 - Fix accounting of buffer data remote headers

   trace_buffer_desc_size() and trace_remote_alloc_buffer() undercount
   the number of pages is needed for the asked for size as it doesn't
   take into account the meta data on each page. Add a helper function
   to do the calculation properly and use that in these functions.

 - Catch nr_page_va overflow in ring_buffer_desc sizing

   The number of pages per remote ring buffer is capped by
   ring_buffer_desc::nr_page_va (32 bits). A buffer_size large enough to
   overflow that field would silently allocate a descriptor smaller than
   what was asked for.

 - Do not resize the subbuf order if any per_cpu buffer is disabled

   The mmapping of ring buffers disables resizing the subbuffers, but it
   is done per-cpu whereas the subbuf size change is done for all the
   per_cpu buffers under the buffer->mutex. It could change the size of
   some while the mapping is happening on others. Have the resize of the
   subbuf order check all the per_cpu buffers under the lock to see if
   any of them is disabled before starting and causing an inconsistency
   between buffers that are being mapped.

* tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (25 commits)
  ring-buffer: Check resize_disabled before publishing the new subbuf order
  tracing/remotes: Catch nr_page_va overflow in ring_buffer_desc sizing
  tracing/remotes: Account for ring buffer page header in size calculation
  tracing: Don't dereference trace_event_file in deferred trigger free
  ftrace: Use rcu_assign_pointer() for tmp_ops filter hash
  ring-buffer: Acquire the lock with irqsave in rb_wake_up_waiters()
  tracing: Take trace_array reference when opening a tracer options file
  tracing: Fix ring_buffer_read_page_size() kernel-doc
  tracing: Restore :mod: trailer after parsing in ftrace_set_clr_event()
  tracing: Fix memory corruption from a "STACKTRACE" histogram key
  tracing: Fix memory corruption from the histogram stacktrace modifier
  tracing: Undo the registration when enabling the histogram trigger fails
  tracing: Take the reference before publishing the named histogram trigger
  tracing: Set the trace clock before registering the histogram trigger
  tracing: Fix typo "preceeded" in comment
  tracing: Fix typo "availabe" in comment
  tracing: Let histogram values keep the percent and graph modifiers
  tracing: Keep the entry count when the histogram stats allocation fails
  tracing: Free histogram the field rejected for a bad modifier
  tracing: Free histogram the var ref when its initialization fails
  ...

1 files changed, 726 insertions, 0 deletions

diff --git a/drivers/video/fbdev/offb.c b/drivers/video/fbdev/offb.c
new file mode 100644
index 000000000..166b2dff3
--- /dev/null
+++ b/drivers/video/fbdev/offb.c
@@ -0,0 +1,726 @@
+/*
+ *  linux/drivers/video/offb.c -- Open Firmware based frame buffer device
+ *
+ *	Copyright (C) 1997 Geert Uytterhoeven
+ *
+ *  This driver is partly based on the PowerMac console driver:
+ *
+ *	Copyright (C) 1996 Paul Mackerras
+ *
+ *  This file is subject to the terms and conditions of the GNU General Public
+ *  License. See the file COPYING in the main directory of this archive for
+ *  more details.
+ */
+
+#include <linux/aperture.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/mm.h>
+#include <linux/vmalloc.h>
+#include <linux/delay.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/interrupt.h>
+#include <linux/fb.h>
+#include <linux/init.h>
+#include <linux/ioport.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+#include <asm/io.h>
+
+#ifdef CONFIG_PPC32
+#include <asm/bootx.h>
+#endif
+
+#include "macmodes.h"
+
+/* Supported palette hacks */
+enum {
+	cmap_unknown,
+	cmap_simple,		/* ATI Mach64 */
+	cmap_r128,		/* ATI Rage128 */
+	cmap_M3A,		/* ATI Rage Mobility M3 Head A */
+	cmap_M3B,		/* ATI Rage Mobility M3 Head B */
+	cmap_radeon,		/* ATI Radeon */
+	cmap_gxt2000,		/* IBM GXT2000 */
+	cmap_avivo,		/* ATI R5xx */
+	cmap_qemu,		/* qemu vga */
+};
+
+struct offb_par {
+	volatile void __iomem *cmap_adr;
+	volatile void __iomem *cmap_data;
+	int cmap_type;
+	int blanked;
+	u32 pseudo_palette[16];
+	resource_size_t base;
+	resource_size_t size;
+};
+
+#ifdef CONFIG_PPC32
+extern boot_infos_t *boot_infos;
+#endif
+
+/* Definitions used by the Avivo palette hack */
+#define AVIVO_DC_LUT_RW_SELECT                  0x6480
+#define AVIVO_DC_LUT_RW_MODE                    0x6484
+#define AVIVO_DC_LUT_RW_INDEX                   0x6488
+#define AVIVO_DC_LUT_SEQ_COLOR                  0x648c
+#define AVIVO_DC_LUT_PWL_DATA                   0x6490
+#define AVIVO_DC_LUT_30_COLOR                   0x6494
+#define AVIVO_DC_LUT_READ_PIPE_SELECT           0x6498
+#define AVIVO_DC_LUT_WRITE_EN_MASK              0x649c
+#define AVIVO_DC_LUT_AUTOFILL                   0x64a0
+
+#define AVIVO_DC_LUTA_CONTROL                   0x64c0
+#define AVIVO_DC_LUTA_BLACK_OFFSET_BLUE         0x64c4
+#define AVIVO_DC_LUTA_BLACK_OFFSET_GREEN        0x64c8
+#define AVIVO_DC_LUTA_BLACK_OFFSET_RED          0x64cc
+#define AVIVO_DC_LUTA_WHITE_OFFSET_BLUE         0x64d0
+#define AVIVO_DC_LUTA_WHITE_OFFSET_GREEN        0x64d4
+#define AVIVO_DC_LUTA_WHITE_OFFSET_RED          0x64d8
+
+#define AVIVO_DC_LUTB_CONTROL                   0x6cc0
+#define AVIVO_DC_LUTB_BLACK_OFFSET_BLUE         0x6cc4
+#define AVIVO_DC_LUTB_BLACK_OFFSET_GREEN        0x6cc8
+#define AVIVO_DC_LUTB_BLACK_OFFSET_RED          0x6ccc
+#define AVIVO_DC_LUTB_WHITE_OFFSET_BLUE         0x6cd0
+#define AVIVO_DC_LUTB_WHITE_OFFSET_GREEN        0x6cd4
+#define AVIVO_DC_LUTB_WHITE_OFFSET_RED          0x6cd8
+
+    /*
+     *  Set a single color register. The values supplied are already
+     *  rounded down to the hardware's capabilities (according to the
+     *  entries in the var structure). Return != 0 for invalid regno.
+     */
+
+static int offb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
+			  u_int transp, struct fb_info *info)
+{
+	struct offb_par *par = (struct offb_par *) info->par;
+
+	if (info->fix.visual == FB_VISUAL_TRUECOLOR) {
+		u32 *pal = info->pseudo_palette;
+		u32 cr = red >> (16 - info->var.red.length);
+		u32 cg = green >> (16 - info->var.green.length);
+		u32 cb = blue >> (16 - info->var.blue.length);
+		u32 value;
+
+		if (regno >= 16)
+			return -EINVAL;
+
+		value = (cr << info->var.red.offset) |
+			(cg << info->var.green.offset) |
+			(cb << info->var.blue.offset);
+		if (info->var.transp.length > 0) {
+			u32 mask = (1 << info->var.transp.length) - 1;
+			mask <<= info->var.transp.offset;
+			value |= mask;
+		}
+		pal[regno] = value;
+		return 0;
+	}
+
+	if (regno > 255)
+		return -EINVAL;
+
+	red >>= 8;
+	green >>= 8;
+	blue >>= 8;
+
+	if (!par->cmap_adr)
+		return 0;
+
+	switch (par->cmap_type) {
+	case cmap_simple:
+		writeb(regno, par->cmap_adr);
+		writeb(red, par->cmap_data);
+		writeb(green, par->cmap_data);
+		writeb(blue, par->cmap_data);
+		break;
+	case cmap_M3A:
+		/* Clear PALETTE_ACCESS_CNTL in DAC_CNTL */
+		out_le32(par->cmap_adr + 0x58,
+			 in_le32(par->cmap_adr + 0x58) & ~0x20);
+		fallthrough;
+	case cmap_r128:
+		/* Set palette index & data */
+		out_8(par->cmap_adr + 0xb0, regno);
+		out_le32(par->cmap_adr + 0xb4,
+			 (red << 16 | green << 8 | blue));
+		break;
+	case cmap_M3B:
+		/* Set PALETTE_ACCESS_CNTL in DAC_CNTL */
+		out_le32(par->cmap_adr + 0x58,
+			 in_le32(par->cmap_adr + 0x58) | 0x20);
+		/* Set palette index & data */
+		out_8(par->cmap_adr + 0xb0, regno);
+		out_le32(par->cmap_adr + 0xb4, (red << 16 | green << 8 | blue));
+		break;
+	case cmap_radeon:
+		/* Set palette index & data (could be smarter) */
+		out_8(par->cmap_adr + 0xb0, regno);
+		out_le32(par->cmap_adr + 0xb4, (red << 16 | green << 8 | blue));
+		break;
+	case cmap_gxt2000:
+		out_le32(((unsigned __iomem *) par->cmap_adr) + regno,
+			 (red << 16 | green << 8 | blue));
+		break;
+	case cmap_avivo:
+		/* Write to both LUTs for now */
+		writel(1, par->cmap_adr + AVIVO_DC_LUT_RW_SELECT);
+		writeb(regno, par->cmap_adr + AVIVO_DC_LUT_RW_INDEX);
+		writel(((red) << 22) | ((green) << 12) | ((blue) << 2),
+		       par->cmap_adr + AVIVO_DC_LUT_30_COLOR);
+		writel(0, par->cmap_adr + AVIVO_DC_LUT_RW_SELECT);
+		writeb(regno, par->cmap_adr + AVIVO_DC_LUT_RW_INDEX);
+		writel(((red) << 22) | ((green) << 12) | ((blue) << 2),
+		       par->cmap_adr + AVIVO_DC_LUT_30_COLOR);
+		break;
+	}
+
+	return 0;
+}
+
+    /*
+     *  Blank the display.
+     */
+
+static int offb_blank(int blank, struct fb_info *info)
+{
+	struct offb_par *par = (struct offb_par *) info->par;
+	int i, j;
+
+	if (!par->cmap_adr)
+		return 0;
+
+	if (!par->blanked)
+		if (!blank)
+			return 0;
+
+	par->blanked = blank;
+
+	if (blank)
+		for (i = 0; i < 256; i++) {
+			switch (par->cmap_type) {
+			case cmap_simple:
+				writeb(i, par->cmap_adr);
+				for (j = 0; j < 3; j++)
+					writeb(0, par->cmap_data);
+				break;
+			case cmap_M3A:
+				/* Clear PALETTE_ACCESS_CNTL in DAC_CNTL */
+				out_le32(par->cmap_adr + 0x58,
+					 in_le32(par->cmap_adr + 0x58) & ~0x20);
+				fallthrough;
+			case cmap_r128:
+				/* Set palette index & data */
+				out_8(par->cmap_adr + 0xb0, i);
+				out_le32(par->cmap_adr + 0xb4, 0);
+				break;
+			case cmap_M3B:
+				/* Set PALETTE_ACCESS_CNTL in DAC_CNTL */
+				out_le32(par->cmap_adr + 0x58,
+					 in_le32(par->cmap_adr + 0x58) | 0x20);
+				/* Set palette index & data */
+				out_8(par->cmap_adr + 0xb0, i);
+				out_le32(par->cmap_adr + 0xb4, 0);
+				break;
+			case cmap_radeon:
+				out_8(par->cmap_adr + 0xb0, i);
+				out_le32(par->cmap_adr + 0xb4, 0);
+				break;
+			case cmap_gxt2000:
+				out_le32(((unsigned __iomem *) par->cmap_adr) + i,
+					 0);
+				break;
+			case cmap_avivo:
+				writel(1, par->cmap_adr + AVIVO_DC_LUT_RW_SELECT);
+				writeb(i, par->cmap_adr + AVIVO_DC_LUT_RW_INDEX);
+				writel(0, par->cmap_adr + AVIVO_DC_LUT_30_COLOR);
+				writel(0, par->cmap_adr + AVIVO_DC_LUT_RW_SELECT);
+				writeb(i, par->cmap_adr + AVIVO_DC_LUT_RW_INDEX);
+				writel(0, par->cmap_adr + AVIVO_DC_LUT_30_COLOR);
+				break;
+			}
+	} else
+		fb_set_cmap(&info->cmap, info);
+	return 0;
+}
+
+static int offb_set_par(struct fb_info *info)
+{
+	struct offb_par *par = (struct offb_par *) info->par;
+
+	/* On avivo, initialize palette control */
+	if (par->cmap_type == cmap_avivo) {
+		writel(0, par->cmap_adr + AVIVO_DC_LUTA_CONTROL);
+		writel(0, par->cmap_adr + AVIVO_DC_LUTA_BLACK_OFFSET_BLUE);
+		writel(0, par->cmap_adr + AVIVO_DC_LUTA_BLACK_OFFSET_GREEN);
+		writel(0, par->cmap_adr + AVIVO_DC_LUTA_BLACK_OFFSET_RED);
+		writel(0x0000ffff, par->cmap_adr + AVIVO_DC_LUTA_WHITE_OFFSET_BLUE);
+		writel(0x0000ffff, par->cmap_adr + AVIVO_DC_LUTA_WHITE_OFFSET_GREEN);
+		writel(0x0000ffff, par->cmap_adr + AVIVO_DC_LUTA_WHITE_OFFSET_RED);
+		writel(0, par->cmap_adr + AVIVO_DC_LUTB_CONTROL);
+		writel(0, par->cmap_adr + AVIVO_DC_LUTB_BLACK_OFFSET_BLUE);
+		writel(0, par->cmap_adr + AVIVO_DC_LUTB_BLACK_OFFSET_GREEN);
+		writel(0, par->cmap_adr + AVIVO_DC_LUTB_BLACK_OFFSET_RED);
+		writel(0x0000ffff, par->cmap_adr + AVIVO_DC_LUTB_WHITE_OFFSET_BLUE);
+		writel(0x0000ffff, par->cmap_adr + AVIVO_DC_LUTB_WHITE_OFFSET_GREEN);
+		writel(0x0000ffff, par->cmap_adr + AVIVO_DC_LUTB_WHITE_OFFSET_RED);
+		writel(1, par->cmap_adr + AVIVO_DC_LUT_RW_SELECT);
+		writel(0, par->cmap_adr + AVIVO_DC_LUT_RW_MODE);
+		writel(0x0000003f, par->cmap_adr + AVIVO_DC_LUT_WRITE_EN_MASK);
+		writel(0, par->cmap_adr + AVIVO_DC_LUT_RW_SELECT);
+		writel(0, par->cmap_adr + AVIVO_DC_LUT_RW_MODE);
+		writel(0x0000003f, par->cmap_adr + AVIVO_DC_LUT_WRITE_EN_MASK);
+	}
+	return 0;
+}
+
+static void offb_destroy(struct fb_info *info)
+{
+	struct offb_par *par = info->par;
+
+	if (info->screen_base)
+		iounmap(info->screen_base);
+	release_mem_region(par->base, par->size);
+	fb_dealloc_cmap(&info->cmap);
+	framebuffer_release(info);
+}
+
+static const struct fb_ops offb_ops = {
+	.owner		= THIS_MODULE,
+	FB_DEFAULT_IOMEM_OPS,
+	.fb_destroy	= offb_destroy,
+	.fb_setcolreg	= offb_setcolreg,
+	.fb_set_par	= offb_set_par,
+	.fb_blank	= offb_blank,
+};
+
+static void __iomem *offb_map_reg(struct device_node *np, int index,
+				  unsigned long offset, unsigned long size)
+{
+	const __be32 *addrp;
+	u64 asize, taddr;
+	unsigned int flags;
+
+	addrp = of_get_pci_address(np, index, &asize, &flags);
+	if (addrp == NULL)
+		addrp = of_get_address(np, index, &asize, &flags);
+	if (addrp == NULL)
+		return NULL;
+	if ((flags & (IORESOURCE_IO | IORESOURCE_MEM)) == 0)
+		return NULL;
+	if ((offset + size) > asize)
+		return NULL;
+	taddr = of_translate_address(np, addrp);
+	if (taddr == OF_BAD_ADDR)
+		return NULL;
+	return ioremap(taddr + offset, size);
+}
+
+static void offb_init_palette_hacks(struct fb_info *info, struct device_node *dp,
+				    unsigned long address)
+{
+	struct offb_par *par = (struct offb_par *) info->par;
+
+	if (of_node_name_prefix(dp, "ATY,Rage128")) {
+		par->cmap_adr = offb_map_reg(dp, 2, 0, 0x1fff);
+		if (par->cmap_adr)
+			par->cmap_type = cmap_r128;
+	} else if (of_node_name_prefix(dp, "ATY,RageM3pA") ||
+		   of_node_name_prefix(dp, "ATY,RageM3p12A")) {
+		par->cmap_adr = offb_map_reg(dp, 2, 0, 0x1fff);
+		if (par->cmap_adr)
+			par->cmap_type = cmap_M3A;
+	} else if (of_node_name_prefix(dp, "ATY,RageM3pB")) {
+		par->cmap_adr = offb_map_reg(dp, 2, 0, 0x1fff);
+		if (par->cmap_adr)
+			par->cmap_type = cmap_M3B;
+	} else if (of_node_name_prefix(dp, "ATY,Rage6")) {
+		par->cmap_adr = offb_map_reg(dp, 1, 0, 0x1fff);
+		if (par->cmap_adr)
+			par->cmap_type = cmap_radeon;
+	} else if (of_node_name_prefix(dp, "ATY,")) {
+		unsigned long base = address & 0xff000000UL;
+		par->cmap_adr =
+			ioremap(base + 0x7ff000, 0x1000) + 0xcc0;
+		par->cmap_data = par->cmap_adr + 1;
+		par->cmap_type = cmap_simple;
+	} else if (dp && (of_device_is_compatible(dp, "pci1014,b7") ||
+			  of_device_is_compatible(dp, "pci1014,21c"))) {
+		par->cmap_adr = offb_map_reg(dp, 0, 0x6000, 0x1000);
+		if (par->cmap_adr)
+			par->cmap_type = cmap_gxt2000;
+	} else if (of_node_name_prefix(dp, "vga,Display-")) {
+		/* Look for AVIVO initialized by SLOF */
+		struct device_node *pciparent __free(device_node) = of_get_parent(dp);
+		const u32 *vid, *did;
+		vid = of_get_property(pciparent, "vendor-id", NULL);
+		did = of_get_property(pciparent, "device-id", NULL);
+		/* This will match most R5xx */
+		if (vid && did && *vid == 0x1002 &&
+		    ((*did >= 0x7100 && *did < 0x7800) ||
+		     (*did >= 0x9400))) {
+			par->cmap_adr = offb_map_reg(pciparent, 2, 0, 0x10000);
+			if (par->cmap_adr)
+				par->cmap_type = cmap_avivo;
+		}
+	} else if (dp && of_device_is_compatible(dp, "qemu,std-vga")) {
+#ifdef __BIG_ENDIAN
+		const __be32 io_of_addr[3] = { 0x01000000, 0x0, 0x0 };
+#else
+		const __be32 io_of_addr[3] = { 0x00000001, 0x0, 0x0 };
+#endif
+		u64 io_addr = of_translate_address(dp, io_of_addr);
+		if (io_addr != OF_BAD_ADDR) {
+			par->cmap_adr = ioremap(io_addr + 0x3c8, 2);
+			if (par->cmap_adr) {
+				par->cmap_type = cmap_simple;
+				par->cmap_data = par->cmap_adr + 1;
+			}
+		}
+	}
+	info->fix.visual = (par->cmap_type != cmap_unknown) ?
+		FB_VISUAL_PSEUDOCOLOR : FB_VISUAL_STATIC_PSEUDOCOLOR;
+}
+
+static void offb_init_fb(struct platform_device *parent, const char *name,
+			 int width, int height, int depth,
+			 int pitch, unsigned long address,
+			 int foreign_endian, struct device_node *dp)
+{
+	unsigned long res_size = pitch * height;
+	unsigned long res_start = address;
+	struct fb_fix_screeninfo *fix;
+	struct fb_var_screeninfo *var;
+	struct fb_info *info;
+	struct offb_par *par;
+
+	if (!request_mem_region(res_start, res_size, "offb"))
+		return;
+
+	printk(KERN_INFO
+	       "Using unsupported %dx%d %s at %lx, depth=%d, pitch=%d\n",
+	       width, height, name, address, depth, pitch);
+	if (depth != 8 && depth != 15 && depth != 16 && depth != 32) {
+		printk(KERN_ERR "%pOF: can't use depth = %d\n", dp, depth);
+		release_mem_region(res_start, res_size);
+		return;
+	}
+
+	info = framebuffer_alloc(sizeof(*par), &parent->dev);
+	if (!info) {
+		release_mem_region(res_start, res_size);
+		return;
+	}
+	platform_set_drvdata(parent, info);
+	par = info->par;
+	fix = &info->fix;
+	var = &info->var;
+
+	if (name)
+		snprintf(fix->id, sizeof(fix->id), "OFfb %s", name);
+	else
+		snprintf(fix->id, sizeof(fix->id), "OFfb %pOFn", dp);
+
+
+	var->xres = var->xres_virtual = width;
+	var->yres = var->yres_virtual = height;
+	fix->line_length = pitch;
+
+	fix->smem_start = address;
+	fix->smem_len = pitch * height;
+	fix->type = FB_TYPE_PACKED_PIXELS;
+	fix->type_aux = 0;
+
+	par->cmap_type = cmap_unknown;
+	if (depth == 8)
+		offb_init_palette_hacks(info, dp, address);
+	else
+		fix->visual = FB_VISUAL_TRUECOLOR;
+
+	var->xoffset = var->yoffset = 0;
+	switch (depth) {
+	case 8:
+		var->bits_per_pixel = 8;
+		var->red.offset = 0;
+		var->red.length = 8;
+		var->green.offset = 0;
+		var->green.length = 8;
+		var->blue.offset = 0;
+		var->blue.length = 8;
+		var->transp.offset = 0;
+		var->transp.length = 0;
+		break;
+	case 15:		/* RGB 555 */
+		var->bits_per_pixel = 16;
+		var->red.offset = 10;
+		var->red.length = 5;
+		var->green.offset = 5;
+		var->green.length = 5;
+		var->blue.offset = 0;
+		var->blue.length = 5;
+		var->transp.offset = 0;
+		var->transp.length = 0;
+		break;
+	case 16:		/* RGB 565 */
+		var->bits_per_pixel = 16;
+		var->red.offset = 11;
+		var->red.length = 5;
+		var->green.offset = 5;
+		var->green.length = 6;
+		var->blue.offset = 0;
+		var->blue.length = 5;
+		var->transp.offset = 0;
+		var->transp.length = 0;
+		break;
+	case 32:		/* RGB 888 */
+		var->bits_per_pixel = 32;
+		var->red.offset = 16;
+		var->red.length = 8;
+		var->green.offset = 8;
+		var->green.length = 8;
+		var->blue.offset = 0;
+		var->blue.length = 8;
+		var->transp.offset = 24;
+		var->transp.length = 8;
+		break;
+	}
+	var->red.msb_right = var->green.msb_right = var->blue.msb_right =
+	    var->transp.msb_right = 0;
+	var->grayscale = 0;
+	var->nonstd = 0;
+	var->activate = 0;
+	var->height = var->width = -1;
+	var->pixclock = 10000;
+	var->left_margin = var->right_margin = 16;
+	var->upper_margin = var->lower_margin = 16;
+	var->hsync_len = var->vsync_len = 8;
+	var->sync = 0;
+	var->vmode = FB_VMODE_NONINTERLACED;
+
+	par->base = address;
+	par->size = fix->smem_len;
+
+	info->fbops = &offb_ops;
+	info->screen_base = ioremap(address, fix->smem_len);
+	info->pseudo_palette = par->pseudo_palette;
+	info->flags = foreign_endian;
+
+	fb_alloc_cmap(&info->cmap, 256, 0);
+
+	if (devm_aperture_acquire_for_platform_device(parent, par->base, par->size) < 0)
+		goto out_err;
+	if (register_framebuffer(info) < 0)
+		goto out_err;
+
+	fb_info(info, "Open Firmware frame buffer device on %pOF\n", dp);
+	return;
+
+out_err:
+	fb_dealloc_cmap(&info->cmap);
+	iounmap(info->screen_base);
+	iounmap(par->cmap_adr);
+	par->cmap_adr = NULL;
+	framebuffer_release(info);
+	release_mem_region(res_start, res_size);
+}
+
+
+static void offb_init_nodriver(struct platform_device *parent, struct device_node *dp,
+			       int no_real_node)
+{
+	unsigned int len;
+	int i, width = 640, height = 480, depth = 8, pitch = 640;
+	unsigned int flags, rsize, addr_prop = 0;
+	unsigned long max_size = 0;
+	u64 rstart, address = OF_BAD_ADDR;
+	const __be32 *pp, *addrp, *up;
+	u64 asize;
+	int foreign_endian = 0;
+
+#ifdef __BIG_ENDIAN
+	if (of_property_read_bool(dp, "little-endian"))
+		foreign_endian = FBINFO_FOREIGN_ENDIAN;
+#else
+	if (of_property_read_bool(dp, "big-endian"))
+		foreign_endian = FBINFO_FOREIGN_ENDIAN;
+#endif
+
+	pp = of_get_property(dp, "linux,bootx-depth", &len);
+	if (pp == NULL)
+		pp = of_get_property(dp, "depth", &len);
+	if (pp && len == sizeof(u32))
+		depth = be32_to_cpup(pp);
+
+	pp = of_get_property(dp, "linux,bootx-width", &len);
+	if (pp == NULL)
+		pp = of_get_property(dp, "width", &len);
+	if (pp && len == sizeof(u32))
+		width = be32_to_cpup(pp);
+
+	pp = of_get_property(dp, "linux,bootx-height", &len);
+	if (pp == NULL)
+		pp = of_get_property(dp, "height", &len);
+	if (pp && len == sizeof(u32))
+		height = be32_to_cpup(pp);
+
+	pp = of_get_property(dp, "linux,bootx-linebytes", &len);
+	if (pp == NULL)
+		pp = of_get_property(dp, "linebytes", &len);
+	if (pp && len == sizeof(u32) && (*pp != 0xffffffffu))
+		pitch = be32_to_cpup(pp);
+	else
+		pitch = width * ((depth + 7) / 8);
+
+	rsize = (unsigned long)pitch * (unsigned long)height;
+
+	/* Ok, now we try to figure out the address of the framebuffer.
+	 *
+	 * Unfortunately, Open Firmware doesn't provide a standard way to do
+	 * so. All we can do is a dodgy heuristic that happens to work in
+	 * practice. On most machines, the "address" property contains what
+	 * we need, though not on Matrox cards found in IBM machines. What I've
+	 * found that appears to give good results is to go through the PCI
+	 * ranges and pick one that is both big enough and if possible encloses
+	 * the "address" property. If none match, we pick the biggest
+	 */
+	up = of_get_property(dp, "linux,bootx-addr", &len);
+	if (up == NULL)
+		up = of_get_property(dp, "address", &len);
+	if (up && len == sizeof(u32))
+		addr_prop = *up;
+
+	/* Hack for when BootX is passing us */
+	if (no_real_node)
+		goto skip_addr;
+
+	for (i = 0; (addrp = of_get_address(dp, i, &asize, &flags))
+		     != NULL; i++) {
+		int match_addrp = 0;
+
+		if (!(flags & IORESOURCE_MEM))
+			continue;
+		if (asize < rsize)
+			continue;
+		rstart = of_translate_address(dp, addrp);
+		if (rstart == OF_BAD_ADDR)
+			continue;
+		if (addr_prop && (rstart <= addr_prop) &&
+		    ((rstart + asize) >= (addr_prop + rsize)))
+			match_addrp = 1;
+		if (match_addrp) {
+			address = addr_prop;
+			break;
+		}
+		if (rsize > max_size) {
+			max_size = rsize;
+			address = OF_BAD_ADDR;
+ 		}
+
+		if (address == OF_BAD_ADDR)
+			address = rstart;
+	}
+ skip_addr:
+	if (address == OF_BAD_ADDR && addr_prop)
+		address = (u64)addr_prop;
+	if (address != OF_BAD_ADDR) {
+#ifdef CONFIG_PCI
+		const __be32 *vidp, *didp;
+		u32 vid, did;
+		struct pci_dev *pdev;
+
+		vidp = of_get_property(dp, "vendor-id", NULL);
+		didp = of_get_property(dp, "device-id", NULL);
+		if (vidp && didp) {
+			vid = be32_to_cpup(vidp);
+			did = be32_to_cpup(didp);
+			pdev = pci_get_device(vid, did, NULL);
+			if (!pdev)
+				return;
+
+			if (pci_enable_device(pdev)) {
+				pci_dev_put(pdev);
+				return;
+			}
+		}
+#endif
+		/* kludge for valkyrie */
+		if (of_node_name_eq(dp, "valkyrie"))
+			address += 0x1000;
+		offb_init_fb(parent, no_real_node ? "bootx" : NULL,
+			     width, height, depth, pitch, address,
+			     foreign_endian, no_real_node ? NULL : dp);
+	}
+}
+
+static void offb_remove(struct platform_device *pdev)
+{
+	struct fb_info *info = platform_get_drvdata(pdev);
+
+	if (info)
+		unregister_framebuffer(info);
+}
+
+static int offb_probe_bootx_noscreen(struct platform_device *pdev)
+{
+	offb_init_nodriver(pdev, of_chosen, 1);
+
+	return 0;
+}
+
+static struct platform_driver offb_driver_bootx_noscreen = {
+	.driver = {
+		.name = "bootx-noscreen",
+	},
+	.probe = offb_probe_bootx_noscreen,
+	.remove = offb_remove,
+};
+
+static int offb_probe_display(struct platform_device *pdev)
+{
+	offb_init_nodriver(pdev, pdev->dev.of_node, 0);
+
+	return 0;
+}
+
+static const struct of_device_id offb_of_match_display[] = {
+	{ .compatible = "display", },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, offb_of_match_display);
+
+static struct platform_driver offb_driver_display = {
+	.driver = {
+		.name = "of-display",
+		.of_match_table = offb_of_match_display,
+	},
+	.probe = offb_probe_display,
+	.remove = offb_remove,
+};
+
+static int __init offb_init(void)
+{
+	if (fb_get_options("offb", NULL))
+		return -ENODEV;
+
+	platform_driver_register(&offb_driver_bootx_noscreen);
+	platform_driver_register(&offb_driver_display);
+
+	return 0;
+}
+module_init(offb_init);
+
+static void __exit offb_exit(void)
+{
+	platform_driver_unregister(&offb_driver_display);
+	platform_driver_unregister(&offb_driver_bootx_noscreen);
+}
+module_exit(offb_exit);
+
+MODULE_DESCRIPTION("Open Firmware frame buffer device driver");
+MODULE_LICENSE("GPL");