From 7901c7998267d9d8c3f1b226a8c8cfd7f8e48a01 Mon Sep 17 00:00:00 2001
From: Ralf Baechle <ralf@linux-mips.org>
Date: Sat, 3 Sep 2005 15:56:11 -0700
Subject: [PATCH] [PATCH] DEC PMAGB B framebuffer update

Revive HX frame buffer support for 2.6.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
---
 drivers/video/pmagb-b-fb.c | 417 +++++++++++++++++++++++++++----------
 include/video/pmagb-b-fb.h |  74 ++++---
 2 files changed, 358 insertions(+), 133 deletions(-)

diff --git a/drivers/video/pmagb-b-fb.c b/drivers/video/pmagb-b-fb.c
index d14eaee91c..a483b13e11 100644
--- a/drivers/video/pmagb-b-fb.c
+++ b/drivers/video/pmagb-b-fb.c
@@ -1,114 +1,128 @@
 /*
- *      linux/drivers/video/pmagb-b-fb.c
+ *	linux/drivers/video/pmagb-b-fb.c
  *
- *	PMAGB-B TurboChannel framebuffer card support ... derived from:
+ *	PMAGB-B TURBOchannel Smart Frame Buffer (SFB) card support,
+ *	derived from:
  *	"HP300 Topcat framebuffer support (derived from macfb of all things)
  *	Phil Blundell <philb@gnu.org> 1998", the original code can be
- *      found in the file hpfb.c in the same directory.
+ *	found in the file hpfb.c in the same directory.
  *
- *      DECstation related code Copyright (C) 1999, 2000, 2001 by
- *      Michael Engel <engel@unix-ag.org>,
- *      Karsten Merker <merker@linuxtag.org> and 
+ *	DECstation related code Copyright (C) 1999, 2000, 2001 by
+ *	Michael Engel <engel@unix-ag.org>,
+ *	Karsten Merker <merker@linuxtag.org> and
  *	Harald Koerfgen.
- *      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.
+ *	Copyright (c) 2005  Maciej W. Rozycki
  *
+ *	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.
  */
 
-/*
- *      We currently only support the PMAGB-B in high resolution mode
- *      as I know of no way to detect low resolution mode set via jumper.
- *      KM, 2001/01/07
- */
-
-#include <linux/module.h>
-#include <linux/kernel.h>
-#include <linux/sched.h>
-#include <linux/errno.h>
-#include <linux/string.h>
-#include <linux/timer.h>
-#include <linux/mm.h>
-#include <linux/tty.h>
-#include <linux/slab.h>
+#include <linux/compiler.h>
 #include <linux/delay.h>
-#include <linux/init.h>
+#include <linux/errno.h>
 #include <linux/fb.h>
-#include <asm/bootinfo.h>
-#include <asm/dec/machtype.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/types.h>
+
+#include <asm/bug.h>
+#include <asm/io.h>
+#include <asm/system.h>
+
 #include <asm/dec/tc.h>
+
 #include <video/pmagb-b-fb.h>
 
-struct pmagb_b_ramdac_regs {
-	unsigned char addr_low;
-	unsigned char pad0[3];
-	unsigned char addr_hi;
-	unsigned char pad1[3];
-	unsigned char data;
-	unsigned char pad2[3];
-	unsigned char cmap;
+
+struct pmagbbfb_par {
+	struct fb_info *next;
+	volatile void __iomem *mmio;
+	volatile void __iomem *smem;
+	volatile u32 __iomem *sfb;
+	volatile u32 __iomem *dac;
+	unsigned int osc0;
+	unsigned int osc1;
+	int slot;
 };
 
-/*
- * Max 3 TURBOchannel slots -> max 3 PMAGB-B :)
- */
-static struct fb_info pmagbb_fb_info[3];
 
-static struct fb_var_screeninfo pmagbbfb_defined = {
-	.xres		= 1280,
-	.yres		= 1024,
-	.xres_virtual	= 1280,
-	.yres_virtual	= 1024,
+static struct fb_info *root_pmagbbfb_dev;
+
+static struct fb_var_screeninfo pmagbbfb_defined __initdata = {
 	.bits_per_pixel	= 8,
 	.red.length	= 8,
 	.green.length	= 8,
 	.blue.length	= 8,
 	.activate	= FB_ACTIVATE_NOW,
-	.height		= 274,
-	.width		= 195,
+	.height		= -1,
+	.width		= -1,
 	.accel_flags	= FB_ACCEL_NONE,
+	.sync		= FB_SYNC_ON_GREEN,
 	.vmode		= FB_VMODE_NONINTERLACED,
 };
 
-static struct fb_fix_screeninfo pmagbafb_fix = {
+static struct fb_fix_screeninfo pmagbbfb_fix __initdata = {
 	.id		= "PMAGB-BA",
-	.smem_len	= (1280 * 1024),
+	.smem_len	= (2048 * 1024),
 	.type		= FB_TYPE_PACKED_PIXELS,
 	.visual		= FB_VISUAL_PSEUDOCOLOR,
-	.line_length	= 1280,
+	.mmio_len	= PMAGB_B_FBMEM,
+};
+
+
+static inline void sfb_write(struct pmagbbfb_par *par, unsigned int reg, u32 v)
+{
+	writel(v, par->sfb + reg / 4);
 }
 
-/*
- * Turn hardware cursor off
- */
-void pmagbbfb_erase_cursor(struct pmagb_b_ramdac_regs *bt459_regs)
+static inline u32 sfb_read(struct pmagbbfb_par *par, unsigned int reg)
+{
+	return readl(par->sfb + reg / 4);
+}
+
+static inline void dac_write(struct pmagbbfb_par *par, unsigned int reg, u8 v)
 {
-	bt459_regs->addr_low = 0;
-	bt459_regs->addr_hi = 3;
-	bt459_regs->data = 0;
+	writeb(v, par->dac + reg / 4);
 }
 
+static inline u8 dac_read(struct pmagbbfb_par *par, unsigned int reg)
+{
+	return readb(par->dac + reg / 4);
+}
+
+static inline void gp0_write(struct pmagbbfb_par *par, u32 v)
+{
+	writel(v, par->mmio + PMAGB_B_GP0);
+}
+
+
 /*
- * Set the palette. 
+ * Set the palette.
  */
-static int pmagbbfb_setcolreg(unsigned regno, unsigned red, unsigned green,
-                              unsigned blue, unsigned transp,
-                              struct fb_info *info)
+static int pmagbbfb_setcolreg(unsigned int regno, unsigned int red,
+			      unsigned int green, unsigned int blue,
+			      unsigned int transp, struct fb_info *info)
 {
-	struct pmagb_b_ramdac_regs *bt459_regs = (struct pmagb_b_ramdac_regs *) info->par;
-	
-	if (regno >= info->cmap.len)
-		return 1;
+	struct pmagbbfb_par *par = info->par;
+
+	BUG_ON(regno >= info->cmap.len);
 
 	red   >>= 8;	/* The cmap fields are 16 bits    */
-	green >>= 8;	/* wide, but the harware colormap */
+	green >>= 8;	/* wide, but the hardware colormap */
 	blue  >>= 8;	/* registers are only 8 bits wide */
 
-	bt459_regs->addr_low = (__u8) regno;
-	bt459_regs->addr_hi = 0;
-	bt459_regs->cmap = red;
-	bt459_regs->cmap = green;
-	bt459_regs->cmap = blue;
+	mb();
+	dac_write(par, BT459_ADDR_LO, regno);
+	dac_write(par, BT459_ADDR_HI, 0x00);
+	wmb();
+	dac_write(par, BT459_CMAP, red);
+	wmb();
+	dac_write(par, BT459_CMAP, green);
+	wmb();
+	dac_write(par, BT459_CMAP, blue);
+
 	return 0;
 }
 
@@ -121,62 +135,247 @@ static struct fb_ops pmagbbfb_ops = {
 	.fb_cursor	= soft_cursor,
 };
 
-int __init pmagbbfb_init_one(int slot)
+
+/*
+ * Turn the hardware cursor off.
+ */
+static void __init pmagbbfb_erase_cursor(struct fb_info *info)
+{
+	struct pmagbbfb_par *par = info->par;
+
+	mb();
+	dac_write(par, BT459_ADDR_LO, 0x00);
+	dac_write(par, BT459_ADDR_HI, 0x03);
+	wmb();
+	dac_write(par, BT459_DATA, 0x00);
+}
+
+/*
+ * Set up screen parameters.
+ */
+static void __init pmagbbfb_screen_setup(struct fb_info *info)
+{
+	struct pmagbbfb_par *par = info->par;
+
+	info->var.xres = ((sfb_read(par, SFB_REG_VID_HOR) >>
+			   SFB_VID_HOR_PIX_SHIFT) & SFB_VID_HOR_PIX_MASK) * 4;
+	info->var.xres_virtual = info->var.xres;
+	info->var.yres = (sfb_read(par, SFB_REG_VID_VER) >>
+			  SFB_VID_VER_SL_SHIFT) & SFB_VID_VER_SL_MASK;
+	info->var.yres_virtual = info->var.yres;
+	info->var.left_margin = ((sfb_read(par, SFB_REG_VID_HOR) >>
+				  SFB_VID_HOR_BP_SHIFT) &
+				 SFB_VID_HOR_BP_MASK) * 4;
+	info->var.right_margin = ((sfb_read(par, SFB_REG_VID_HOR) >>
+				   SFB_VID_HOR_FP_SHIFT) &
+				  SFB_VID_HOR_FP_MASK) * 4;
+	info->var.upper_margin = (sfb_read(par, SFB_REG_VID_VER) >>
+				  SFB_VID_VER_BP_SHIFT) & SFB_VID_VER_BP_MASK;
+	info->var.lower_margin = (sfb_read(par, SFB_REG_VID_VER) >>
+				  SFB_VID_VER_FP_SHIFT) & SFB_VID_VER_FP_MASK;
+	info->var.hsync_len = ((sfb_read(par, SFB_REG_VID_HOR) >>
+				SFB_VID_HOR_SYN_SHIFT) &
+			       SFB_VID_HOR_SYN_MASK) * 4;
+	info->var.vsync_len = (sfb_read(par, SFB_REG_VID_VER) >>
+			       SFB_VID_VER_SYN_SHIFT) & SFB_VID_VER_SYN_MASK;
+
+	info->fix.line_length = info->var.xres;
+};
+
+/*
+ * Determine oscillator configuration.
+ */
+static void __init pmagbbfb_osc_setup(struct fb_info *info)
 {
-	unsigned long base_addr = get_tc_base_addr(slot);
-	struct fb_info *info = &pmagbb_fb_info[slot];
-
-	printk("PMAGB-BA framebuffer in slot %d\n", slot);
-	/*
-	 * Framebuffer display memory base address and friends
-	 */
-	pmagbbfb_fix.smem_start = base_addr + PMAGB_B_ONBOARD_FBMEM_OFFSET;
-	info->par = (base_addr + PMAGB_B_BT459_OFFSET); 
-	
-	/*
-	 * Configure the Bt459 RAM DAC
-	 */
-	pmagbbfb_erase_cursor((struct pmagb_b_ramdac_regs *) info->par);
-
-	/*
-	 *      Let there be consoles..
-	 */
+	static unsigned int pmagbbfb_freqs[] __initdata = {
+		130808, 119843, 104000, 92980, 74367, 72800,
+		69197, 66000, 65000, 50350, 36000, 32000, 25175
+	};
+	struct pmagbbfb_par *par = info->par;
+	u32 count0 = 8, count1 = 8, counttc = 16 * 256 + 8;
+	u32 freq0, freq1, freqtc = get_tc_speed() / 250;
+	int i, j;
+
+	gp0_write(par, 0);				/* select Osc0 */
+	for (j = 0; j < 16; j++) {
+		mb();
+		sfb_write(par, SFB_REG_TCCLK_COUNT, 0);
+		mb();
+		for (i = 0; i < 100; i++) {	/* nominally max. 20.5us */
+			if (sfb_read(par, SFB_REG_TCCLK_COUNT) == 0)
+				break;
+			udelay(1);
+		}
+		count0 += sfb_read(par, SFB_REG_VIDCLK_COUNT);
+	}
+
+	gp0_write(par, 1);				/* select Osc1 */
+	for (j = 0; j < 16; j++) {
+		mb();
+		sfb_write(par, SFB_REG_TCCLK_COUNT, 0);
+
+		for (i = 0; i < 100; i++) {	/* nominally max. 20.5us */
+			if (sfb_read(par, SFB_REG_TCCLK_COUNT) == 0)
+				break;
+			udelay(1);
+		}
+		count1 += sfb_read(par, SFB_REG_VIDCLK_COUNT);
+	}
+
+	freq0 = (freqtc * count0 + counttc / 2) / counttc;
+	par->osc0 = freq0;
+	if (freq0 >= pmagbbfb_freqs[0] - (pmagbbfb_freqs[0] + 32) / 64 &&
+	    freq0 <= pmagbbfb_freqs[0] + (pmagbbfb_freqs[0] + 32) / 64)
+		par->osc0 = pmagbbfb_freqs[0];
+
+	freq1 = (par->osc0 * count1 + count0 / 2) / count0;
+	par->osc1 = freq1;
+	for (i = 0; i < sizeof(pmagbbfb_freqs) / sizeof(*pmagbbfb_freqs); i++)
+		if (freq1 >= pmagbbfb_freqs[i] -
+			     (pmagbbfb_freqs[i] + 128) / 256 &&
+		    freq1 <= pmagbbfb_freqs[i] +
+			     (pmagbbfb_freqs[i] + 128) / 256) {
+			par->osc1 = pmagbbfb_freqs[i];
+			break;
+		}
+
+	if (par->osc0 - par->osc1 <= (par->osc0 + par->osc1 + 256) / 512 ||
+	    par->osc1 - par->osc0 <= (par->osc0 + par->osc1 + 256) / 512)
+		par->osc1 = 0;
+
+	gp0_write(par, par->osc1 != 0);			/* reselect OscX */
+
+	info->var.pixclock = par->osc1 ?
+			     (1000000000 + par->osc1 / 2) / par->osc1 :
+			     (1000000000 + par->osc0 / 2) / par->osc0;
+};
+
+
+static int __init pmagbbfb_init_one(int slot)
+{
+	char freq0[12], freq1[12];
+	struct fb_info *info;
+	struct pmagbbfb_par *par;
+	unsigned long base_addr;
+	u32 vid_base;
+
+	info = framebuffer_alloc(sizeof(struct pmagbbfb_par), NULL);
+	if (!info)
+		return -ENOMEM;
+
+	par = info->par;
+	par->slot = slot;
+	claim_tc_card(par->slot);
+
+	base_addr = get_tc_base_addr(par->slot);
+
+	par->next = root_pmagbbfb_dev;
+	root_pmagbbfb_dev = info;
+
+	if (fb_alloc_cmap(&info->cmap, 256, 0) < 0)
+		goto err_alloc;
+
 	info->fbops = &pmagbbfb_ops;
-	info->var = pmagbbfb_defined;
 	info->fix = pmagbbfb_fix;
-	info->screen_base = pmagbbfb_fix.smem_start; 
+	info->var = pmagbbfb_defined;
 	info->flags = FBINFO_DEFAULT;
 
-	fb_alloc_cmap(&fb_info.cmap, 256, 0);
+	/* MMIO mapping setup.  */
+	info->fix.mmio_start = base_addr;
+	par->mmio = ioremap_nocache(info->fix.mmio_start, info->fix.mmio_len);
+	if (!par->mmio)
+		goto err_cmap;
+	par->sfb = par->mmio + PMAGB_B_SFB;
+	par->dac = par->mmio + PMAGB_B_BT459;
+
+	/* Frame buffer mapping setup.  */
+	info->fix.smem_start = base_addr + PMAGB_B_FBMEM;
+	par->smem = ioremap_nocache(info->fix.smem_start, info->fix.smem_len);
+	if (!par->smem)
+		goto err_mmio_map;
+	vid_base = sfb_read(par, SFB_REG_VID_BASE);
+	info->screen_base = (void __iomem *)par->smem + vid_base * 0x1000;
+	info->screen_size = info->fix.smem_len - 2 * vid_base * 0x1000;
+
+	pmagbbfb_erase_cursor(info);
+	pmagbbfb_screen_setup(info);
+	pmagbbfb_osc_setup(info);
 
 	if (register_framebuffer(info) < 0)
-		return 1;
+		goto err_smem_map;
+
+	snprintf(freq0, sizeof(freq0), "%u.%03uMHz",
+		 par->osc0 / 1000, par->osc0 % 1000);
+	snprintf(freq1, sizeof(freq1), "%u.%03uMHz",
+		 par->osc1 / 1000, par->osc1 % 1000);
+
+	pr_info("fb%d: %s frame buffer device in slot %d\n",
+		info->node, info->fix.id, par->slot);
+	pr_info("fb%d: Osc0: %s, Osc1: %s, Osc%u selected\n",
+		info->node, freq0, par->osc1 ? freq1 : "disabled",
+		par->osc1 != 0);
+
 	return 0;
+
+
+err_smem_map:
+	iounmap(par->smem);
+
+err_mmio_map:
+	iounmap(par->mmio);
+
+err_cmap:
+	fb_dealloc_cmap(&info->cmap);
+
+err_alloc:
+	root_pmagbbfb_dev = par->next;
+	release_tc_card(par->slot);
+	framebuffer_release(info);
+	return -ENXIO;
 }
 
-/* 
- * Initialise the framebuffer
- */
+static void __exit pmagbbfb_exit_one(void)
+{
+	struct fb_info *info = root_pmagbbfb_dev;
+	struct pmagbbfb_par *par = info->par;
+
+	unregister_framebuffer(info);
+	iounmap(par->smem);
+	iounmap(par->mmio);
+	fb_dealloc_cmap(&info->cmap);
+	root_pmagbbfb_dev = par->next;
+	release_tc_card(par->slot);
+	framebuffer_release(info);
+}
 
-int __init pmagbbfb_init(void)
+
+/*
+ * Initialise the framebuffer.
+ */
+static int __init pmagbbfb_init(void)
 {
-	int sid;
-	int found = 0;
+	int count = 0;
+	int slot;
 
 	if (fb_get_options("pmagbbfb", NULL))
-		return -ENODEV;
+		return -ENXIO;
 
-	if (TURBOCHANNEL) {
-		while ((sid = search_tc_card("PMAGB-BA")) >= 0) {
-			found = 1;
-			claim_tc_card(sid);
-			pmagbbfb_init_one(sid);
-		}
-		return found ? 0 : -ENODEV;
-	} else {
-		return -ENODEV;
+	while ((slot = search_tc_card("PMAGB-BA")) >= 0) {
+		if (pmagbbfb_init_one(slot) < 0)
+			break;
+		count++;
 	}
+	return (count > 0) ? 0 : -ENXIO;
+}
+
+static void __exit pmagbbfb_exit(void)
+{
+	while (root_pmagbbfb_dev)
+		pmagbbfb_exit_one();
 }
 
+
 module_init(pmagbbfb_init);
+module_exit(pmagbbfb_exit);
+
 MODULE_LICENSE("GPL");
diff --git a/include/video/pmagb-b-fb.h b/include/video/pmagb-b-fb.h
index 87b81a5551..7539b9087a 100644
--- a/include/video/pmagb-b-fb.h
+++ b/include/video/pmagb-b-fb.h
@@ -1,32 +1,58 @@
 /*
- *      linux/drivers/video/pmagb-b-fb.h
+ *	linux/include/video/pmagb-b-fb.h
  *
- *      TurboChannel PMAGB-B framebuffer card support,
- *      Copyright (C) 1999, 2000, 2001 by
- *      Michael Engel <engel@unix-ag.org> and 
- *      Karsten Merker <merker@linuxtag.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.
+ *	TURBOchannel PMAGB-B Smart Frame Buffer (SFB) card support,
+ *	Copyright (C) 1999, 2000, 2001 by
+ *	Michael Engel <engel@unix-ag.org> and
+ *	Karsten Merker <merker@linuxtag.org>
+ *	Copyright (c) 2005  Maciej W. Rozycki
+ *
+ *	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.
  */
 
+/* IOmem resource offsets.  */
+#define PMAGB_B_ROM		0x000000	/* REX option ROM */
+#define PMAGB_B_SFB		0x100000	/* SFB ASIC */
+#define PMAGB_B_GP0		0x140000	/* general purpose output 0 */
+#define PMAGB_B_GP1		0x180000	/* general purpose output 1 */
+#define PMAGB_B_BT459		0x1c0000	/* Bt459 RAMDAC */
+#define PMAGB_B_FBMEM		0x200000	/* frame buffer */
+#define PMAGB_B_SIZE		0x400000	/* address space size */
 
-/*
- * Bt459 RAM DAC register base offset (rel. to TC slot base address)
- */
-#define PMAGB_B_BT459_OFFSET			0x001C0000
+/* IOmem register offsets.  */
+#define SFB_REG_VID_HOR		0x64		/* video horizontal setup */
+#define SFB_REG_VID_VER		0x68		/* video vertical setup */
+#define SFB_REG_VID_BASE	0x6c		/* video base address */
+#define SFB_REG_TCCLK_COUNT	0x78		/* TURBOchannel clock count */
+#define SFB_REG_VIDCLK_COUNT	0x7c		/* video clock count */
 
-/*
- * Begin of PMAGB-B framebuffer memory, resolution is configurable:
- * 1024x864x8 or 1280x1024x8, settable by jumper on the card
- */
-#define PMAGB_B_ONBOARD_FBMEM_OFFSET	0x00201000
+/* Video horizontal setup register constants.  All bits are r/w.  */
+#define SFB_VID_HOR_BP_SHIFT	0x15		/* back porch */
+#define SFB_VID_HOR_BP_MASK	0x7f
+#define SFB_VID_HOR_SYN_SHIFT	0x0e		/* sync pulse */
+#define SFB_VID_HOR_SYN_MASK	0x7f
+#define SFB_VID_HOR_FP_SHIFT	0x09		/* front porch */
+#define SFB_VID_HOR_FP_MASK	0x1f
+#define SFB_VID_HOR_PIX_SHIFT	0x00		/* active video */
+#define SFB_VID_HOR_PIX_MASK	0x1ff
 
-/*
- * Bt459 register offsets, byte-wide registers
- */
+/* Video vertical setup register constants.  All bits are r/w.  */
+#define SFB_VID_VER_BP_SHIFT	0x16		/* back porch */
+#define SFB_VID_VER_BP_MASK	0x3f
+#define SFB_VID_VER_SYN_SHIFT	0x10		/* sync pulse */
+#define SFB_VID_VER_SYN_MASK	0x3f
+#define SFB_VID_VER_FP_SHIFT	0x0b		/* front porch */
+#define SFB_VID_VER_FP_MASK	0x1f
+#define SFB_VID_VER_SL_SHIFT	0x00		/* active scan lines */
+#define SFB_VID_VER_SL_MASK	0x7ff
+
+/* Video base address register constants.  All bits are r/w.  */
+#define SFB_VID_BASE_MASK	0x1ff		/* video base row address */
 
-#define BT459_ADR_LOW			BT459_OFFSET + 0x00	/* addr. low */
-#define BT459_ADR_HIGH			BT459_OFFSET + 0x04	/* addr. high */
-#define BT459_DATA			BT459_OFFSET + 0x08	/* r/w data */
-#define BT459_CMAP			BT459_OFFSET + 0x0C	/* color map */
+/* Bt459 register offsets, byte-wide registers.  */
+#define BT459_ADDR_LO		0x0		/* address low */
+#define BT459_ADDR_HI		0x4		/* address high */
+#define BT459_DATA		0x8		/* data window register */
+#define BT459_CMAP		0xc		/* color map window register */
-- 
2.39.5