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, 1018 insertions, 0 deletions

diff --git a/drivers/video/fbdev/controlfb.c b/drivers/video/fbdev/controlfb.c
new file mode 100644
index 000000000..4bb821d7f
--- /dev/null
+++ b/drivers/video/fbdev/controlfb.c
@@ -0,0 +1,1018 @@
+/*
+ *  controlfb.c -- frame buffer device for the PowerMac 'control' display
+ *
+ *  Created 12 July 1998 by Dan Jacobowitz <dan@debian.org>
+ *  Copyright (C) 1998 Dan Jacobowitz
+ *  Copyright (C) 2001 Takashi Oe
+ *
+ *  Mmap code by Michel Lanners <mlan@cpu.lu>
+ *
+ *  Frame buffer structure from:
+ *    drivers/video/chipsfb.c -- frame buffer device for
+ *    Chips & Technologies 65550 chip.
+ *
+ *    Copyright (C) 1998 Paul Mackerras
+ *
+ *    This file is derived from the Powermac "chips" driver:
+ *    Copyright (C) 1997 Fabio Riccardi.
+ *    And from the frame buffer device for Open Firmware-initialized devices:
+ *    Copyright (C) 1997 Geert Uytterhoeven.
+ *
+ *  Hardware information from:
+ *    control.c: Console support for PowerMac "control" display adaptor.
+ *    Copyright (C) 1996 Paul Mackerras
+ *
+ *  Updated to 2.5 framebuffer API by Ben Herrenschmidt
+ *  <benh@kernel.crashing.org>, Paul Mackerras <paulus@samba.org>,
+ *  and James Simmons <jsimmons@infradead.org>.
+ *
+ *  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/kernel.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/fb.h>
+#include <linux/init.h>
+#include <linux/pci.h>
+#include <linux/nvram.h>
+#include <linux/adb.h>
+#include <linux/cuda.h>
+#ifdef CONFIG_BOOTX_TEXT
+#include <asm/btext.h>
+#endif
+
+#include "macmodes.h"
+#include "controlfb.h"
+
+#if !defined(CONFIG_PPC_PMAC) || !defined(CONFIG_PPC32)
+#define invalid_vram_cache(addr)
+#undef in_8
+#undef out_8
+#undef in_le32
+#undef out_le32
+#define in_8(addr)		0
+#define out_8(addr, val)	(void)(val)
+#define in_le32(addr)		0
+#define out_le32(addr, val)	(void)(val)
+#ifndef pgprot_cached_wthru
+#define pgprot_cached_wthru(prot) (prot)
+#endif
+#else
+static void invalid_vram_cache(void __force *addr)
+{
+	eieio();
+	dcbf(addr);
+	mb();
+	eieio();
+	dcbf(addr);
+	mb();
+}
+#endif
+
+struct fb_par_control {
+	int	vmode, cmode;
+	int	xres, yres;
+	int	vxres, vyres;
+	int	xoffset, yoffset;
+	int	pitch;
+	struct control_regvals	regvals;
+	unsigned long sync;
+	unsigned char ctrl;
+};
+
+#define DIRTY(z) ((x)->z != (y)->z)
+#define DIRTY_CMAP(z) (memcmp(&((x)->z), &((y)->z), sizeof((y)->z)))
+static inline int PAR_EQUAL(struct fb_par_control *x, struct fb_par_control *y)
+{
+	int i, results;
+
+	results = 1;
+	for (i = 0; i < 3; i++)
+		results &= !DIRTY(regvals.clock_params[i]);
+	if (!results)
+		return 0;
+	for (i = 0; i < 16; i++)
+		results &= !DIRTY(regvals.regs[i]);
+	if (!results)
+		return 0;
+	return (!DIRTY(cmode) && !DIRTY(xres) && !DIRTY(yres)
+		&& !DIRTY(vxres) && !DIRTY(vyres));
+}
+
+struct fb_info_control {
+	struct fb_info		info;
+	struct fb_par_control	par;
+	u32			pseudo_palette[16];
+
+	struct cmap_regs	__iomem *cmap_regs;
+	unsigned long		cmap_regs_phys;
+
+	struct control_regs	__iomem *control_regs;
+	unsigned long		control_regs_phys;
+	unsigned long		control_regs_size;
+
+	__u8			__iomem *frame_buffer;
+	unsigned long		frame_buffer_phys;
+	unsigned long		fb_orig_base;
+	unsigned long		fb_orig_size;
+
+	int			control_use_bank2;
+	unsigned long		total_vram;
+	unsigned char		vram_attr;
+};
+
+/* control register access macro */
+#define CNTRL_REG(INFO,REG) (&(((INFO)->control_regs->REG).r))
+
+
+/************************** Internal variables *******************************/
+
+static struct fb_info_control *control_fb;
+
+static int default_vmode __initdata = VMODE_NVRAM;
+static int default_cmode __initdata = CMODE_NVRAM;
+
+
+static int controlfb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
+			     u_int transp, struct fb_info *info)
+{
+	struct fb_info_control *p =
+		container_of(info, struct fb_info_control, info);
+	__u8 r, g, b;
+
+	if (regno > 255)
+		return 1;
+
+	r = red >> 8;
+	g = green >> 8;
+	b = blue >> 8;
+
+	out_8(&p->cmap_regs->addr, regno);	/* tell clut what addr to fill	*/
+	out_8(&p->cmap_regs->lut, r);		/* send one color channel at	*/
+	out_8(&p->cmap_regs->lut, g);		/* a time...			*/
+	out_8(&p->cmap_regs->lut, b);
+
+	if (regno < 16) {
+		int i;
+		switch (p->par.cmode) {
+		case CMODE_16:
+			p->pseudo_palette[regno] =
+			    (regno << 10) | (regno << 5) | regno;
+			break;
+		case CMODE_32:
+			i = (regno << 8) | regno;
+			p->pseudo_palette[regno] = (i << 16) | i;
+			break;
+		}
+	}
+
+	return 0;
+}
+
+
+/********************  End of controlfb_ops implementation  ******************/
+
+
+
+static void set_control_clock(unsigned char *params)
+{
+#ifdef CONFIG_ADB_CUDA
+	struct adb_request req;
+	int i;
+
+	for (i = 0; i < 3; ++i) {
+		cuda_request(&req, NULL, 5, CUDA_PACKET, CUDA_GET_SET_IIC,
+			     0x50, i + 1, params[i]);
+		while (!req.complete)
+			cuda_poll();
+	}
+#endif
+}
+
+/*
+ * Set screen start address according to var offset values
+ */
+static inline void set_screen_start(int xoffset, int yoffset,
+	struct fb_info_control *p)
+{
+	struct fb_par_control *par = &p->par;
+
+	par->xoffset = xoffset;
+	par->yoffset = yoffset;
+	out_le32(CNTRL_REG(p,start_addr),
+		 par->yoffset * par->pitch + (par->xoffset << par->cmode));
+}
+
+#define RADACAL_WRITE(a,d) \
+	out_8(&p->cmap_regs->addr, (a)); \
+	out_8(&p->cmap_regs->dat,   (d))
+
+/* Now how about actually saying, Make it so! */
+/* Some things in here probably don't need to be done each time. */
+static void control_set_hardware(struct fb_info_control *p, struct fb_par_control *par)
+{
+	struct control_regvals	*r;
+	volatile struct preg	__iomem *rp;
+	int			i, cmode;
+
+	if (PAR_EQUAL(&p->par, par)) {
+		/*
+		 * check if only xoffset or yoffset differs.
+		 * this prevents flickers in typical VT switch case.
+		 */
+		if (p->par.xoffset != par->xoffset ||
+		    p->par.yoffset != par->yoffset)
+			set_screen_start(par->xoffset, par->yoffset, p);
+
+		return;
+	}
+
+	p->par = *par;
+	cmode = p->par.cmode;
+	r = &par->regvals;
+
+	/* Turn off display */
+	out_le32(CNTRL_REG(p,ctrl), 0x400 | par->ctrl);
+
+	set_control_clock(r->clock_params);
+
+	RADACAL_WRITE(0x20, r->radacal_ctrl);
+	RADACAL_WRITE(0x21, p->control_use_bank2 ? 0 : 1);
+	RADACAL_WRITE(0x10, 0);
+	RADACAL_WRITE(0x11, 0);
+
+	rp = &p->control_regs->vswin;
+	for (i = 0; i < 16; ++i, ++rp)
+		out_le32(&rp->r, r->regs[i]);
+
+	out_le32(CNTRL_REG(p,pitch), par->pitch);
+	out_le32(CNTRL_REG(p,mode), r->mode);
+	out_le32(CNTRL_REG(p,vram_attr), p->vram_attr);
+	out_le32(CNTRL_REG(p,start_addr), par->yoffset * par->pitch
+		 + (par->xoffset << cmode));
+	out_le32(CNTRL_REG(p,rfrcnt), 0x1e5);
+	out_le32(CNTRL_REG(p,intr_ena), 0);
+
+	/* Turn on display */
+	out_le32(CNTRL_REG(p,ctrl), par->ctrl);
+
+#ifdef CONFIG_BOOTX_TEXT
+	btext_update_display(p->frame_buffer_phys + CTRLFB_OFF,
+			     p->par.xres, p->par.yres,
+			     (cmode == CMODE_32? 32: cmode == CMODE_16? 16: 8),
+			     p->par.pitch);
+#endif /* CONFIG_BOOTX_TEXT */
+}
+
+/* Work out which banks of VRAM we have installed. */
+/* danj: I guess the card just ignores writes to nonexistant VRAM... */
+
+static void __init find_vram_size(struct fb_info_control *p)
+{
+	int bank1, bank2;
+
+	/*
+	 * Set VRAM in 2MB (bank 1) mode
+	 * VRAM Bank 2 will be accessible through offset 0x600000 if present
+	 * and VRAM Bank 1 will not respond at that offset even if present
+	 */
+	out_le32(CNTRL_REG(p,vram_attr), 0x31);
+
+	out_8(&p->frame_buffer[0x600000], 0xb3);
+	out_8(&p->frame_buffer[0x600001], 0x71);
+	invalid_vram_cache(&p->frame_buffer[0x600000]);
+
+	bank2 = (in_8(&p->frame_buffer[0x600000]) == 0xb3)
+		&& (in_8(&p->frame_buffer[0x600001]) == 0x71);
+
+	/*
+	 * Set VRAM in 2MB (bank 2) mode
+	 * VRAM Bank 1 will be accessible through offset 0x000000 if present
+	 * and VRAM Bank 2 will not respond at that offset even if present
+	 */
+	out_le32(CNTRL_REG(p,vram_attr), 0x39);
+
+	out_8(&p->frame_buffer[0], 0x5a);
+	out_8(&p->frame_buffer[1], 0xc7);
+	invalid_vram_cache(&p->frame_buffer[0]);
+
+	bank1 = (in_8(&p->frame_buffer[0]) == 0x5a)
+		&& (in_8(&p->frame_buffer[1]) == 0xc7);
+
+	if (bank2) {
+		if (!bank1) {
+			/*
+			 * vram bank 2 only
+			 */
+			p->control_use_bank2 = 1;
+			p->vram_attr = 0x39;
+			p->frame_buffer += 0x600000;
+			p->frame_buffer_phys += 0x600000;
+		} else {
+			/*
+			 * 4 MB vram
+			 */
+			p->vram_attr = 0x51;
+		}
+	} else {
+		/*
+		 * vram bank 1 only
+		 */
+		p->vram_attr = 0x31;
+	}
+
+        p->total_vram = (bank1 + bank2) * 0x200000;
+
+	printk(KERN_INFO "controlfb: VRAM Total = %dMB "
+			"(%dMB @ bank 1, %dMB @ bank 2)\n",
+			(bank1 + bank2) << 1, bank1 << 1, bank2 << 1);
+}
+
+/*
+ * Get the monitor sense value.
+ * Note that this can be called before calibrate_delay,
+ * so we can't use udelay.
+ */
+static int read_control_sense(struct fb_info_control *p)
+{
+	int sense;
+
+	out_le32(CNTRL_REG(p,mon_sense), 7);	/* drive all lines high */
+	__delay(200);
+	out_le32(CNTRL_REG(p,mon_sense), 077);	/* turn off drivers */
+	__delay(2000);
+	sense = (in_le32(CNTRL_REG(p,mon_sense)) & 0x1c0) << 2;
+
+	/* drive each sense line low in turn and collect the other 2 */
+	out_le32(CNTRL_REG(p,mon_sense), 033);	/* drive A low */
+	__delay(2000);
+	sense |= (in_le32(CNTRL_REG(p,mon_sense)) & 0xc0) >> 2;
+	out_le32(CNTRL_REG(p,mon_sense), 055);	/* drive B low */
+	__delay(2000);
+	sense |= ((in_le32(CNTRL_REG(p,mon_sense)) & 0x100) >> 5)
+		| ((in_le32(CNTRL_REG(p,mon_sense)) & 0x40) >> 4);
+	out_le32(CNTRL_REG(p,mon_sense), 066);	/* drive C low */
+	__delay(2000);
+	sense |= (in_le32(CNTRL_REG(p,mon_sense)) & 0x180) >> 7;
+
+	out_le32(CNTRL_REG(p,mon_sense), 077);	/* turn off drivers */
+
+	return sense;
+}
+
+/**********************  Various translation functions  **********************/
+
+#define CONTROL_PIXCLOCK_BASE	256016
+#define CONTROL_PIXCLOCK_MIN	5000	/* ~ 200 MHz dot clock */
+
+/*
+ * calculate the clock parameters to be sent to CUDA according to given
+ * pixclock in pico second.
+ */
+static int calc_clock_params(unsigned long clk, unsigned char *param)
+{
+	unsigned long p0, p1, p2, k, l, m, n, min;
+
+	if (clk > (CONTROL_PIXCLOCK_BASE << 3))
+		return 1;
+
+	p2 = ((clk << 4) < CONTROL_PIXCLOCK_BASE)? 3: 2;
+	l = clk << p2;
+	p0 = 0;
+	p1 = 0;
+	for (k = 1, min = l; k < 32; k++) {
+		unsigned long rem;
+
+		m = CONTROL_PIXCLOCK_BASE * k;
+		n = m / l;
+		rem = m % l;
+		if (n && (n < 128) && rem < min) {
+			p0 = k;
+			p1 = n;
+			min = rem;
+		}
+	}
+	if (!p0 || !p1)
+		return 1;
+
+	param[0] = p0;
+	param[1] = p1;
+	param[2] = p2;
+
+	return 0;
+}
+
+
+/*
+ * This routine takes a user-supplied var, and picks the best vmode/cmode
+ * from it.
+ */
+
+static int control_var_to_par(struct fb_var_screeninfo *var,
+	struct fb_par_control *par, const struct fb_info *fb_info)
+{
+	int cmode, piped_diff, hstep;
+	unsigned hperiod, hssync, hsblank, hesync, heblank, piped, heq, hlfln,
+		 hserr, vperiod, vssync, vesync, veblank, vsblank, vswin, vewin;
+	unsigned long pixclock;
+	struct fb_info_control *p =
+		container_of(fb_info, struct fb_info_control, info);
+	struct control_regvals *r = &par->regvals;
+
+	switch (var->bits_per_pixel) {
+	case 8:
+		par->cmode = CMODE_8;
+		if (p->total_vram > 0x200000) {
+			r->mode = 3;
+			r->radacal_ctrl = 0x20;
+			piped_diff = 13;
+		} else {
+			r->mode = 2;
+			r->radacal_ctrl = 0x10;
+			piped_diff = 9;
+		}
+		break;
+	case 15:
+	case 16:
+		par->cmode = CMODE_16;
+		if (p->total_vram > 0x200000) {
+			r->mode = 2;
+			r->radacal_ctrl = 0x24;
+			piped_diff = 5;
+		} else {
+			r->mode = 1;
+			r->radacal_ctrl = 0x14;
+			piped_diff = 3;
+		}
+		break;
+	case 32:
+		par->cmode = CMODE_32;
+		if (p->total_vram > 0x200000) {
+			r->mode = 1;
+			r->radacal_ctrl = 0x28;
+		} else {
+			r->mode = 0;
+			r->radacal_ctrl = 0x18;
+		}
+		piped_diff = 1;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	/*
+	 * adjust xres and vxres so that the corresponding memory widths are
+	 * 32-byte aligned
+	 */
+	hstep = 31 >> par->cmode;
+	par->xres = (var->xres + hstep) & ~hstep;
+	par->vxres = (var->xres_virtual + hstep) & ~hstep;
+	par->xoffset = (var->xoffset + hstep) & ~hstep;
+	if (par->vxres < par->xres)
+		par->vxres = par->xres;
+	par->pitch = par->vxres << par->cmode;
+
+	par->yres = var->yres;
+	par->vyres = var->yres_virtual;
+	par->yoffset = var->yoffset;
+	if (par->vyres < par->yres)
+		par->vyres = par->yres;
+
+	par->sync = var->sync;
+
+	if (par->pitch * par->vyres + CTRLFB_OFF > p->total_vram)
+		return -EINVAL;
+
+	if (par->xoffset + par->xres > par->vxres)
+		par->xoffset = par->vxres - par->xres;
+	if (par->yoffset + par->yres > par->vyres)
+		par->yoffset = par->vyres - par->yres;
+
+	pixclock = (var->pixclock < CONTROL_PIXCLOCK_MIN)? CONTROL_PIXCLOCK_MIN:
+		   var->pixclock;
+	if (calc_clock_params(pixclock, r->clock_params))
+		return -EINVAL;
+
+	hperiod = ((var->left_margin + par->xres + var->right_margin
+		    + var->hsync_len) >> 1) - 2;
+	hssync = hperiod + 1;
+	hsblank = hssync - (var->right_margin >> 1);
+	hesync = (var->hsync_len >> 1) - 1;
+	heblank = (var->left_margin >> 1) + hesync;
+	piped = heblank - piped_diff;
+	heq = var->hsync_len >> 2;
+	hlfln = (hperiod+2) >> 1;
+	hserr = hssync-hesync;
+	vperiod = (var->vsync_len + var->lower_margin + par->yres
+		   + var->upper_margin) << 1;
+	vssync = vperiod - 2;
+	vesync = (var->vsync_len << 1) - vperiod + vssync;
+	veblank = (var->upper_margin << 1) + vesync;
+	vsblank = vssync - (var->lower_margin << 1);
+	vswin = (vsblank+vssync) >> 1;
+	vewin = (vesync+veblank) >> 1;
+
+	r->regs[0] = vswin;
+	r->regs[1] = vsblank;
+	r->regs[2] = veblank;
+	r->regs[3] = vewin;
+	r->regs[4] = vesync;
+	r->regs[5] = vssync;
+	r->regs[6] = vperiod;
+	r->regs[7] = piped;
+	r->regs[8] = hperiod;
+	r->regs[9] = hsblank;
+	r->regs[10] = heblank;
+	r->regs[11] = hesync;
+	r->regs[12] = hssync;
+	r->regs[13] = heq;
+	r->regs[14] = hlfln;
+	r->regs[15] = hserr;
+
+	if (par->xres >= 1280 && par->cmode >= CMODE_16)
+		par->ctrl = 0x7f;
+	else
+		par->ctrl = 0x3b;
+
+	if (mac_var_to_vmode(var, &par->vmode, &cmode))
+		par->vmode = 0;
+
+	return 0;
+}
+
+
+/*
+ * Convert hardware data in par to an fb_var_screeninfo
+ */
+
+static void control_par_to_var(struct fb_par_control *par, struct fb_var_screeninfo *var)
+{
+	struct control_regints *rv;
+
+	rv = (struct control_regints *) par->regvals.regs;
+
+	memset(var, 0, sizeof(*var));
+	var->xres = par->xres;
+	var->yres = par->yres;
+	var->xres_virtual = par->vxres;
+	var->yres_virtual = par->vyres;
+	var->xoffset = par->xoffset;
+	var->yoffset = par->yoffset;
+
+	switch(par->cmode) {
+	default:
+	case CMODE_8:
+		var->bits_per_pixel = 8;
+		var->red.length = 8;
+		var->green.length = 8;
+		var->blue.length = 8;
+		break;
+	case CMODE_16:	/* 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.length = 5;
+		break;
+	case CMODE_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.length = 8;
+		var->transp.offset = 24;
+		var->transp.length = 8;
+		break;
+	}
+	var->height = -1;
+	var->width = -1;
+	var->vmode = FB_VMODE_NONINTERLACED;
+
+	var->left_margin = (rv->heblank - rv->hesync) << 1;
+	var->right_margin = (rv->hssync - rv->hsblank) << 1;
+	var->hsync_len = (rv->hperiod + 2 - rv->hssync + rv->hesync) << 1;
+
+	var->upper_margin = (rv->veblank - rv->vesync) >> 1;
+	var->lower_margin = (rv->vssync - rv->vsblank) >> 1;
+	var->vsync_len = (rv->vperiod - rv->vssync + rv->vesync) >> 1;
+
+	var->sync = par->sync;
+
+	/*
+	 * 10^12 * clock_params[0] / (3906400 * clock_params[1]
+	 *			      * 2^clock_params[2])
+	 * (10^12 * clock_params[0] / (3906400 * clock_params[1]))
+	 * >> clock_params[2]
+	 */
+	/* (255990.17 * clock_params[0] / clock_params[1]) >> clock_params[2] */
+	var->pixclock = CONTROL_PIXCLOCK_BASE * par->regvals.clock_params[0];
+	var->pixclock /= par->regvals.clock_params[1];
+	var->pixclock >>= par->regvals.clock_params[2];
+}
+
+/********************  The functions for controlfb_ops ********************/
+
+/*
+ * Checks a var structure
+ */
+static int controlfb_check_var (struct fb_var_screeninfo *var, struct fb_info *info)
+{
+	struct fb_par_control par;
+	int err;
+
+	err = control_var_to_par(var, &par, info);
+	if (err)
+		return err;
+	control_par_to_var(&par, var);
+
+	return 0;
+}
+
+/*
+ * Applies current var to display
+ */
+static int controlfb_set_par (struct fb_info *info)
+{
+	struct fb_info_control *p =
+		container_of(info, struct fb_info_control, info);
+	struct fb_par_control par;
+	int err;
+
+	if((err = control_var_to_par(&info->var, &par, info))) {
+		printk (KERN_ERR "controlfb_set_par: error calling"
+				 " control_var_to_par: %d.\n", err);
+		return err;
+	}
+
+	control_set_hardware(p, &par);
+
+	info->fix.visual = (p->par.cmode == CMODE_8) ?
+		FB_VISUAL_PSEUDOCOLOR : FB_VISUAL_DIRECTCOLOR;
+	info->fix.line_length = p->par.pitch;
+	info->fix.xpanstep = 32 >> p->par.cmode;
+	info->fix.ypanstep = 1;
+
+	return 0;
+}
+
+static int controlfb_pan_display(struct fb_var_screeninfo *var,
+				 struct fb_info *info)
+{
+	unsigned int xoffset, hstep;
+	struct fb_info_control *p =
+		container_of(info, struct fb_info_control, info);
+	struct fb_par_control *par = &p->par;
+
+	/*
+	 * make sure start addr will be 32-byte aligned
+	 */
+	hstep = 0x1f >> par->cmode;
+	xoffset = (var->xoffset + hstep) & ~hstep;
+
+	if (xoffset+par->xres > par->vxres ||
+	    var->yoffset+par->yres > par->vyres)
+		return -EINVAL;
+
+	set_screen_start(xoffset, var->yoffset, p);
+
+	return 0;
+}
+
+static int controlfb_blank(int blank_mode, struct fb_info *info)
+{
+	struct fb_info_control __maybe_unused *p =
+		container_of(info, struct fb_info_control, info);
+	unsigned ctrl;
+
+	ctrl = in_le32(CNTRL_REG(p, ctrl));
+	if (blank_mode > 0)
+		switch (blank_mode) {
+		case FB_BLANK_VSYNC_SUSPEND:
+			ctrl &= ~3;
+			break;
+		case FB_BLANK_HSYNC_SUSPEND:
+			ctrl &= ~0x30;
+			break;
+		case FB_BLANK_POWERDOWN:
+			ctrl &= ~0x33;
+			fallthrough;
+		case FB_BLANK_NORMAL:
+			ctrl |= 0x400;
+			break;
+		default:
+			break;
+		}
+	else {
+		ctrl &= ~0x400;
+		ctrl |= 0x33;
+	}
+	out_le32(CNTRL_REG(p,ctrl), ctrl);
+
+	return 0;
+}
+
+/*
+ * Private mmap since we want to have a different caching on the framebuffer
+ * for controlfb.
+ * Note there's no locking in here; it's done in fb_mmap() in fbmem.c.
+ */
+static int controlfb_mmap(struct fb_info *info,
+                       struct vm_area_struct *vma)
+{
+	unsigned long mmio_pgoff;
+	unsigned long start;
+	u32 len;
+
+	start = info->fix.smem_start;
+	len = info->fix.smem_len;
+	mmio_pgoff = PAGE_ALIGN((start & ~PAGE_MASK) + len) >> PAGE_SHIFT;
+	if (vma->vm_pgoff >= mmio_pgoff) {
+		if (info->var.accel_flags)
+			return -EINVAL;
+		vma->vm_pgoff -= mmio_pgoff;
+		start = info->fix.mmio_start;
+		len = info->fix.mmio_len;
+		vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
+	} else {
+		/* framebuffer */
+		vma->vm_page_prot = pgprot_cached_wthru(vma->vm_page_prot);
+	}
+
+	return vm_iomap_memory(vma, start, len);
+}
+
+static const struct fb_ops controlfb_ops = {
+	.owner		= THIS_MODULE,
+	__FB_DEFAULT_IOMEM_OPS_RDWR,
+	.fb_check_var	= controlfb_check_var,
+	.fb_set_par	= controlfb_set_par,
+	.fb_setcolreg	= controlfb_setcolreg,
+	.fb_pan_display = controlfb_pan_display,
+	.fb_blank	= controlfb_blank,
+	__FB_DEFAULT_IOMEM_OPS_DRAW,
+	.fb_mmap	= controlfb_mmap,
+};
+
+/*
+ * Set misc info vars for this driver
+ */
+static void __init control_init_info(struct fb_info *info, struct fb_info_control *p)
+{
+	/* Fill fb_info */
+	info->par = &p->par;
+	info->fbops = &controlfb_ops;
+	info->pseudo_palette = p->pseudo_palette;
+	info->flags = FBINFO_HWACCEL_YPAN;
+	info->screen_base = p->frame_buffer + CTRLFB_OFF;
+
+	fb_alloc_cmap(&info->cmap, 256, 0);
+
+	/* Fill fix common fields */
+	strcpy(info->fix.id, "control");
+	info->fix.mmio_start = p->control_regs_phys;
+	info->fix.mmio_len = sizeof(struct control_regs);
+	info->fix.type = FB_TYPE_PACKED_PIXELS;
+	info->fix.smem_start = p->frame_buffer_phys + CTRLFB_OFF;
+	info->fix.smem_len = p->total_vram - CTRLFB_OFF;
+        info->fix.ywrapstep = 0;
+        info->fix.type_aux = 0;
+        info->fix.accel = FB_ACCEL_NONE;
+}
+
+/*
+ * Parse user specified options (`video=controlfb:')
+ */
+static void __init control_setup(char *options)
+{
+	char *this_opt;
+
+	if (!options || !*options)
+		return;
+
+	while ((this_opt = strsep(&options, ",")) != NULL) {
+		if (!strncmp(this_opt, "vmode:", 6)) {
+			int vmode = simple_strtoul(this_opt+6, NULL, 0);
+			if (vmode > 0 && vmode <= VMODE_MAX &&
+			    control_mac_modes[vmode - 1].m[1] >= 0)
+				default_vmode = vmode;
+		} else if (!strncmp(this_opt, "cmode:", 6)) {
+			int depth = simple_strtoul(this_opt+6, NULL, 0);
+			switch (depth) {
+			 case CMODE_8:
+			 case CMODE_16:
+			 case CMODE_32:
+			 	default_cmode = depth;
+			 	break;
+			 case 8:
+				default_cmode = CMODE_8;
+				break;
+			 case 15:
+			 case 16:
+				default_cmode = CMODE_16;
+				break;
+			 case 24:
+			 case 32:
+				default_cmode = CMODE_32;
+				break;
+			}
+		}
+	}
+}
+
+/*
+ * finish off the driver initialization and register
+ */
+static int __init init_control(struct fb_info_control *p)
+{
+	int full, sense, vmode, cmode, vyres;
+	struct fb_var_screeninfo var;
+	int rc;
+
+	printk(KERN_INFO "controlfb: ");
+
+	full = p->total_vram == 0x400000;
+
+	/* Try to pick a video mode out of NVRAM if we have one. */
+	cmode = default_cmode;
+	if (IS_REACHABLE(CONFIG_NVRAM) && cmode == CMODE_NVRAM)
+		cmode = nvram_read_byte(NV_CMODE);
+	if (cmode < CMODE_8 || cmode > CMODE_32)
+		cmode = CMODE_8;
+
+	vmode = default_vmode;
+	if (IS_REACHABLE(CONFIG_NVRAM) && vmode == VMODE_NVRAM)
+		vmode = nvram_read_byte(NV_VMODE);
+	if (vmode < 1 || vmode > VMODE_MAX ||
+	    control_mac_modes[vmode - 1].m[full] < cmode) {
+		sense = read_control_sense(p);
+		printk(KERN_CONT "Monitor sense value = 0x%x, ", sense);
+		vmode = mac_map_monitor_sense(sense);
+		if (control_mac_modes[vmode - 1].m[full] < 0)
+			vmode = VMODE_640_480_60;
+		cmode = min(cmode, control_mac_modes[vmode - 1].m[full]);
+	}
+
+	/* Initialize info structure */
+	control_init_info(&p->info, p);
+
+	/* Setup default var */
+	if (mac_vmode_to_var(vmode, cmode, &var) < 0) {
+		/* This shouldn't happen! */
+		printk("mac_vmode_to_var(%d, %d,) failed\n", vmode, cmode);
+try_again:
+		vmode = VMODE_640_480_60;
+		cmode = CMODE_8;
+		if (mac_vmode_to_var(vmode, cmode, &var) < 0) {
+			printk(KERN_ERR "controlfb: mac_vmode_to_var() failed\n");
+			return -ENXIO;
+		}
+		printk(KERN_INFO "controlfb: ");
+	}
+	printk("using video mode %d and color mode %d.\n", vmode, cmode);
+
+	vyres = (p->total_vram - CTRLFB_OFF) / (var.xres << cmode);
+	if (vyres > var.yres)
+		var.yres_virtual = vyres;
+
+	/* Apply default var */
+	var.activate = FB_ACTIVATE_NOW;
+	rc = fb_set_var(&p->info, &var);
+	if (rc && (vmode != VMODE_640_480_60 || cmode != CMODE_8))
+		goto try_again;
+
+	/* Register with fbdev layer */
+	if (register_framebuffer(&p->info) < 0)
+		return -ENXIO;
+
+	fb_info(&p->info, "control display adapter\n");
+
+	return 0;
+}
+
+static void control_cleanup(void)
+{
+	struct fb_info_control	*p = control_fb;
+
+	if (!p)
+		return;
+
+	if (p->cmap_regs)
+		iounmap(p->cmap_regs);
+	if (p->control_regs)
+		iounmap(p->control_regs);
+	if (p->frame_buffer) {
+		if (p->control_use_bank2)
+			p->frame_buffer -= 0x600000;
+		iounmap(p->frame_buffer);
+	}
+	if (p->cmap_regs_phys)
+		release_mem_region(p->cmap_regs_phys, 0x1000);
+	if (p->control_regs_phys)
+		release_mem_region(p->control_regs_phys, p->control_regs_size);
+	if (p->fb_orig_base)
+		release_mem_region(p->fb_orig_base, p->fb_orig_size);
+	kfree(p);
+}
+
+/*
+ * find "control" and initialize
+ */
+static int __init control_of_init(struct device_node *dp)
+{
+	struct fb_info_control	*p;
+	struct resource		fb_res, reg_res;
+
+	if (control_fb) {
+		printk(KERN_ERR "controlfb: only one control is supported\n");
+		return -ENXIO;
+	}
+
+	if (of_pci_address_to_resource(dp, 2, &fb_res) ||
+	    of_pci_address_to_resource(dp, 1, &reg_res)) {
+		printk(KERN_ERR "can't get 2 addresses for control\n");
+		return -ENXIO;
+	}
+	p = kzalloc_obj(*p);
+	if (!p)
+		return -ENOMEM;
+	control_fb = p;	/* save it for cleanups */
+
+	/* Map in frame buffer and registers */
+	p->fb_orig_base = fb_res.start;
+	p->fb_orig_size = resource_size(&fb_res);
+	/* use the big-endian aperture (??) */
+	p->frame_buffer_phys = fb_res.start + 0x800000;
+	p->control_regs_phys = reg_res.start;
+	p->control_regs_size = resource_size(&reg_res);
+
+	if (!p->fb_orig_base ||
+	    !request_mem_region(p->fb_orig_base,p->fb_orig_size,"controlfb")) {
+		p->fb_orig_base = 0;
+		goto error_out;
+	}
+	/* map at most 8MB for the frame buffer */
+	p->frame_buffer = ioremap_wt(p->frame_buffer_phys, 0x800000);
+
+	if (!p->control_regs_phys ||
+	    !request_mem_region(p->control_regs_phys, p->control_regs_size,
+	    "controlfb regs")) {
+		p->control_regs_phys = 0;
+		goto error_out;
+	}
+	p->control_regs = ioremap(p->control_regs_phys, p->control_regs_size);
+
+	p->cmap_regs_phys = 0xf301b000;	 /* XXX not in prom? */
+	if (!request_mem_region(p->cmap_regs_phys, 0x1000, "controlfb cmap")) {
+		p->cmap_regs_phys = 0;
+		goto error_out;
+	}
+	p->cmap_regs = ioremap(p->cmap_regs_phys, 0x1000);
+
+	if (!p->cmap_regs || !p->control_regs || !p->frame_buffer)
+		goto error_out;
+
+	find_vram_size(p);
+	if (!p->total_vram)
+		goto error_out;
+
+	if (init_control(p) < 0)
+		goto error_out;
+
+	return 0;
+
+error_out:
+	control_cleanup();
+	return -ENXIO;
+}
+
+static int __init control_init(void)
+{
+	struct device_node *dp;
+	char *option = NULL;
+	int ret = -ENXIO;
+
+	if (fb_get_options("controlfb", &option))
+		return -ENODEV;
+	control_setup(option);
+
+	dp = of_find_node_by_name(NULL, "control");
+	if (dp && !control_of_init(dp))
+		ret = 0;
+	of_node_put(dp);
+
+	return ret;
+}
+
+device_initcall(control_init);