2 * Xilinx TFT frame buffer driver
4 * Author: MontaVista Software, Inc.
7 * 2002-2007 (c) MontaVista Software, Inc.
8 * 2007 (c) Secret Lab Technologies, Ltd.
11 * This file is licensed under the terms of the GNU General Public License
12 * version 2. This program is licensed "as is" without any warranty of any
13 * kind, whether express or implied.
17 * This driver was based on au1100fb.c by MontaVista rewritten for 2.6
18 * by Embedded Alley Solutions <source@embeddedalley.com>, which in turn
19 * was based on skeletonfb.c, Skeleton for a frame buffer device by
23 #include <linux/device.h>
24 #include <linux/module.h>
25 #include <linux/kernel.h>
26 #include <linux/errno.h>
27 #include <linux/string.h>
30 #include <linux/init.h>
31 #include <linux/dma-mapping.h>
32 #include <linux/of_device.h>
33 #include <linux/of_platform.h>
34 #include <linux/of_address.h>
36 #include <linux/slab.h>
42 #define DRIVER_NAME "xilinxfb"
45 * Xilinx calls it "TFT LCD Controller" though it can also be used for
46 * the VGA port on the Xilinx ML40x board. This is a hardware display
47 * controller for a 640x480 resolution TFT or VGA screen.
49 * The interface to the framebuffer is nice and simple. There are two
50 * control registers. The first tells the LCD interface where in memory
51 * the frame buffer is (only the 11 most significant bits are used, so
52 * don't start thinking about scrolling). The second allows the LCD to
53 * be turned on or off as well as rotated 180 degrees.
55 * In case of direct BUS access the second control register will be at
56 * an offset of 4 as compared to the DCR access where the offset is 1
57 * i.e. REG_CTRL. So this is taken care in the function
58 * xilinx_fb_out32 where it left shifts the offset 2 times in case of
64 #define REG_CTRL_ENABLE 0x0001
65 #define REG_CTRL_ROTATE 0x0002
68 * The hardware only handles a single mode: 640x480 24 bit true
69 * color. Each pixel gets a word (32 bits) of memory. Within each word,
70 * the 8 most significant bits are ignored, the next 8 bits are the red
71 * level, the next 8 bits are the green level and the 8 least
72 * significant bits are the blue level. Each row of the LCD uses 1024
73 * words, but only the first 640 pixels are displayed with the other 384
74 * words being ignored. There are 480 rows.
76 #define BYTES_PER_PIXEL 4
77 #define BITS_PER_PIXEL (BYTES_PER_PIXEL * 8)
83 #define PALETTE_ENTRIES_NO 16 /* passed to fb_alloc_cmap() */
85 /* ML300/403 reference design framebuffer driver platform data struct */
86 struct xilinxfb_platform_data
{
87 u32 rotate_screen
; /* Flag to rotate display 180 degrees */
88 u32 screen_height_mm
; /* Physical dimensions of screen in mm */
90 u32 xres
, yres
; /* resolution of screen in pixels */
91 u32 xvirt
, yvirt
; /* resolution of memory buffer */
93 /* Physical address of framebuffer memory; If non-zero, driver
94 * will use provided memory address instead of allocating one from
95 * the consistent pool.
101 * Default xilinxfb configuration
103 static const struct xilinxfb_platform_data xilinx_fb_default_pdata
= {
111 * Here are the default fb_fix_screeninfo and fb_var_screeninfo structures
113 static const struct fb_fix_screeninfo xilinx_fb_fix
= {
115 .type
= FB_TYPE_PACKED_PIXELS
,
116 .visual
= FB_VISUAL_TRUECOLOR
,
117 .accel
= FB_ACCEL_NONE
120 static const struct fb_var_screeninfo xilinx_fb_var
= {
121 .bits_per_pixel
= BITS_PER_PIXEL
,
123 .red
= { RED_SHIFT
, 8, 0 },
124 .green
= { GREEN_SHIFT
, 8, 0 },
125 .blue
= { BLUE_SHIFT
, 8, 0 },
126 .transp
= { 0, 0, 0 },
128 .activate
= FB_ACTIVATE_NOW
131 #define BUS_ACCESS_FLAG 0x1 /* 1 = BUS, 0 = DCR */
132 #define LITTLE_ENDIAN_ACCESS 0x2 /* LITTLE ENDIAN IO functions */
134 struct xilinxfb_drvdata
{
135 struct fb_info info
; /* FB driver info record */
137 phys_addr_t regs_phys
; /* phys. address of the control
140 void __iomem
*regs
; /* virt. address of the control
143 #ifdef CONFIG_PPC_DCR
145 unsigned int dcr_len
;
147 void *fb_virt
; /* virt. address of the frame buffer */
148 dma_addr_t fb_phys
; /* phys. address of the frame buffer */
149 int fb_alloced
; /* Flag, was the fb memory alloced? */
151 u8 flags
; /* features of the driver */
153 u32 reg_ctrl_default
;
155 u32 pseudo_palette
[PALETTE_ENTRIES_NO
];
156 /* Fake palette of 16 colors */
159 #define to_xilinxfb_drvdata(_info) \
160 container_of(_info, struct xilinxfb_drvdata, info)
163 * The XPS TFT Controller can be accessed through BUS or DCR interface.
164 * To perform the read/write on the registers we need to check on
165 * which bus its connected and call the appropriate write API.
167 static void xilinx_fb_out32(struct xilinxfb_drvdata
*drvdata
, u32 offset
,
170 if (drvdata
->flags
& BUS_ACCESS_FLAG
) {
171 if (drvdata
->flags
& LITTLE_ENDIAN_ACCESS
)
172 iowrite32(val
, drvdata
->regs
+ (offset
<< 2));
174 iowrite32be(val
, drvdata
->regs
+ (offset
<< 2));
176 #ifdef CONFIG_PPC_DCR
178 dcr_write(drvdata
->dcr_host
, offset
, val
);
182 static u32
xilinx_fb_in32(struct xilinxfb_drvdata
*drvdata
, u32 offset
)
184 if (drvdata
->flags
& BUS_ACCESS_FLAG
) {
185 if (drvdata
->flags
& LITTLE_ENDIAN_ACCESS
)
186 return ioread32(drvdata
->regs
+ (offset
<< 2));
188 return ioread32be(drvdata
->regs
+ (offset
<< 2));
190 #ifdef CONFIG_PPC_DCR
192 return dcr_read(drvdata
->dcr_host
, offset
);
198 xilinx_fb_setcolreg(unsigned int regno
, unsigned int red
, unsigned int green
,
199 unsigned int blue
, unsigned int transp
, struct fb_info
*fbi
)
201 u32
*palette
= fbi
->pseudo_palette
;
203 if (regno
>= PALETTE_ENTRIES_NO
)
206 if (fbi
->var
.grayscale
) {
207 /* Convert color to grayscale.
208 * grayscale = 0.30*R + 0.59*G + 0.11*B
210 blue
= (red
* 77 + green
* 151 + blue
* 28 + 127) >> 8;
215 /* fbi->fix.visual is always FB_VISUAL_TRUECOLOR */
217 /* We only handle 8 bits of each color. */
221 palette
[regno
] = (red
<< RED_SHIFT
) | (green
<< GREEN_SHIFT
) |
222 (blue
<< BLUE_SHIFT
);
228 xilinx_fb_blank(int blank_mode
, struct fb_info
*fbi
)
230 struct xilinxfb_drvdata
*drvdata
= to_xilinxfb_drvdata(fbi
);
232 switch (blank_mode
) {
233 case FB_BLANK_UNBLANK
:
235 xilinx_fb_out32(drvdata
, REG_CTRL
, drvdata
->reg_ctrl_default
);
238 case FB_BLANK_NORMAL
:
239 case FB_BLANK_VSYNC_SUSPEND
:
240 case FB_BLANK_HSYNC_SUSPEND
:
241 case FB_BLANK_POWERDOWN
:
243 xilinx_fb_out32(drvdata
, REG_CTRL
, 0);
247 return 0; /* success */
250 static const struct fb_ops xilinxfb_ops
= {
251 .owner
= THIS_MODULE
,
252 .fb_setcolreg
= xilinx_fb_setcolreg
,
253 .fb_blank
= xilinx_fb_blank
,
254 .fb_fillrect
= cfb_fillrect
,
255 .fb_copyarea
= cfb_copyarea
,
256 .fb_imageblit
= cfb_imageblit
,
259 /* ---------------------------------------------------------------------
260 * Bus independent setup/teardown
263 static int xilinxfb_assign(struct platform_device
*pdev
,
264 struct xilinxfb_drvdata
*drvdata
,
265 struct xilinxfb_platform_data
*pdata
)
268 struct device
*dev
= &pdev
->dev
;
269 int fbsize
= pdata
->xvirt
* pdata
->yvirt
* BYTES_PER_PIXEL
;
271 if (drvdata
->flags
& BUS_ACCESS_FLAG
) {
272 struct resource
*res
;
274 res
= platform_get_resource(pdev
, IORESOURCE_MEM
, 0);
275 drvdata
->regs
= devm_ioremap_resource(&pdev
->dev
, res
);
276 if (IS_ERR(drvdata
->regs
))
277 return PTR_ERR(drvdata
->regs
);
279 drvdata
->regs_phys
= res
->start
;
282 /* Allocate the framebuffer memory */
283 if (pdata
->fb_phys
) {
284 drvdata
->fb_phys
= pdata
->fb_phys
;
285 drvdata
->fb_virt
= ioremap(pdata
->fb_phys
, fbsize
);
287 drvdata
->fb_alloced
= 1;
288 drvdata
->fb_virt
= dma_alloc_coherent(dev
, PAGE_ALIGN(fbsize
),
293 if (!drvdata
->fb_virt
) {
294 dev_err(dev
, "Could not allocate frame buffer memory\n");
298 /* Clear (turn to black) the framebuffer */
299 memset_io((void __iomem
*)drvdata
->fb_virt
, 0, fbsize
);
301 /* Tell the hardware where the frame buffer is */
302 xilinx_fb_out32(drvdata
, REG_FB_ADDR
, drvdata
->fb_phys
);
303 rc
= xilinx_fb_in32(drvdata
, REG_FB_ADDR
);
304 /* Endianness detection */
305 if (rc
!= drvdata
->fb_phys
) {
306 drvdata
->flags
|= LITTLE_ENDIAN_ACCESS
;
307 xilinx_fb_out32(drvdata
, REG_FB_ADDR
, drvdata
->fb_phys
);
310 /* Turn on the display */
311 drvdata
->reg_ctrl_default
= REG_CTRL_ENABLE
;
312 if (pdata
->rotate_screen
)
313 drvdata
->reg_ctrl_default
|= REG_CTRL_ROTATE
;
314 xilinx_fb_out32(drvdata
, REG_CTRL
, drvdata
->reg_ctrl_default
);
316 /* Fill struct fb_info */
317 drvdata
->info
.device
= dev
;
318 drvdata
->info
.screen_base
= (void __iomem
*)drvdata
->fb_virt
;
319 drvdata
->info
.fbops
= &xilinxfb_ops
;
320 drvdata
->info
.fix
= xilinx_fb_fix
;
321 drvdata
->info
.fix
.smem_start
= drvdata
->fb_phys
;
322 drvdata
->info
.fix
.smem_len
= fbsize
;
323 drvdata
->info
.fix
.line_length
= pdata
->xvirt
* BYTES_PER_PIXEL
;
325 drvdata
->info
.pseudo_palette
= drvdata
->pseudo_palette
;
326 drvdata
->info
.flags
= FBINFO_DEFAULT
;
327 drvdata
->info
.var
= xilinx_fb_var
;
328 drvdata
->info
.var
.height
= pdata
->screen_height_mm
;
329 drvdata
->info
.var
.width
= pdata
->screen_width_mm
;
330 drvdata
->info
.var
.xres
= pdata
->xres
;
331 drvdata
->info
.var
.yres
= pdata
->yres
;
332 drvdata
->info
.var
.xres_virtual
= pdata
->xvirt
;
333 drvdata
->info
.var
.yres_virtual
= pdata
->yvirt
;
335 /* Allocate a colour map */
336 rc
= fb_alloc_cmap(&drvdata
->info
.cmap
, PALETTE_ENTRIES_NO
, 0);
338 dev_err(dev
, "Fail to allocate colormap (%d entries)\n",
343 /* Register new frame buffer */
344 rc
= register_framebuffer(&drvdata
->info
);
346 dev_err(dev
, "Could not register frame buffer\n");
350 if (drvdata
->flags
& BUS_ACCESS_FLAG
) {
351 /* Put a banner in the log (for DEBUG) */
352 dev_dbg(dev
, "regs: phys=%pa, virt=%p\n",
353 &drvdata
->regs_phys
, drvdata
->regs
);
355 /* Put a banner in the log (for DEBUG) */
356 dev_dbg(dev
, "fb: phys=%llx, virt=%p, size=%x\n",
357 (unsigned long long)drvdata
->fb_phys
, drvdata
->fb_virt
, fbsize
);
359 return 0; /* success */
362 fb_dealloc_cmap(&drvdata
->info
.cmap
);
365 if (drvdata
->fb_alloced
)
366 dma_free_coherent(dev
, PAGE_ALIGN(fbsize
), drvdata
->fb_virt
,
369 iounmap(drvdata
->fb_virt
);
371 /* Turn off the display */
372 xilinx_fb_out32(drvdata
, REG_CTRL
, 0);
377 static int xilinxfb_release(struct device
*dev
)
379 struct xilinxfb_drvdata
*drvdata
= dev_get_drvdata(dev
);
381 #if !defined(CONFIG_FRAMEBUFFER_CONSOLE) && defined(CONFIG_LOGO)
382 xilinx_fb_blank(VESA_POWERDOWN
, &drvdata
->info
);
385 unregister_framebuffer(&drvdata
->info
);
387 fb_dealloc_cmap(&drvdata
->info
.cmap
);
389 if (drvdata
->fb_alloced
)
390 dma_free_coherent(dev
, PAGE_ALIGN(drvdata
->info
.fix
.smem_len
),
391 drvdata
->fb_virt
, drvdata
->fb_phys
);
393 iounmap(drvdata
->fb_virt
);
395 /* Turn off the display */
396 xilinx_fb_out32(drvdata
, REG_CTRL
, 0);
398 #ifdef CONFIG_PPC_DCR
399 /* Release the resources, as allocated based on interface */
400 if (!(drvdata
->flags
& BUS_ACCESS_FLAG
))
401 dcr_unmap(drvdata
->dcr_host
, drvdata
->dcr_len
);
407 /* ---------------------------------------------------------------------
411 static int xilinxfb_of_probe(struct platform_device
*pdev
)
415 struct xilinxfb_platform_data pdata
;
417 struct xilinxfb_drvdata
*drvdata
;
419 /* Copy with the default pdata (not a ptr reference!) */
420 pdata
= xilinx_fb_default_pdata
;
422 /* Allocate the driver data region */
423 drvdata
= devm_kzalloc(&pdev
->dev
, sizeof(*drvdata
), GFP_KERNEL
);
428 * To check whether the core is connected directly to DCR or BUS
429 * interface and initialize the tft_access accordingly.
431 of_property_read_u32(pdev
->dev
.of_node
, "xlnx,dcr-splb-slave-if",
435 * Fill the resource structure if its direct BUS interface
436 * otherwise fill the dcr_host structure.
439 drvdata
->flags
|= BUS_ACCESS_FLAG
;
440 #ifdef CONFIG_PPC_DCR
444 start
= dcr_resource_start(pdev
->dev
.of_node
, 0);
445 drvdata
->dcr_len
= dcr_resource_len(pdev
->dev
.of_node
, 0);
446 drvdata
->dcr_host
= dcr_map(pdev
->dev
.of_node
, start
, drvdata
->dcr_len
);
447 if (!DCR_MAP_OK(drvdata
->dcr_host
)) {
448 dev_err(&pdev
->dev
, "invalid DCR address\n");
454 prop
= of_get_property(pdev
->dev
.of_node
, "phys-size", &size
);
455 if ((prop
) && (size
>= sizeof(u32
) * 2)) {
456 pdata
.screen_width_mm
= prop
[0];
457 pdata
.screen_height_mm
= prop
[1];
460 prop
= of_get_property(pdev
->dev
.of_node
, "resolution", &size
);
461 if ((prop
) && (size
>= sizeof(u32
) * 2)) {
462 pdata
.xres
= prop
[0];
463 pdata
.yres
= prop
[1];
466 prop
= of_get_property(pdev
->dev
.of_node
, "virtual-resolution", &size
);
467 if ((prop
) && (size
>= sizeof(u32
) * 2)) {
468 pdata
.xvirt
= prop
[0];
469 pdata
.yvirt
= prop
[1];
472 if (of_find_property(pdev
->dev
.of_node
, "rotate-display", NULL
))
473 pdata
.rotate_screen
= 1;
475 dev_set_drvdata(&pdev
->dev
, drvdata
);
476 return xilinxfb_assign(pdev
, drvdata
, &pdata
);
479 static int xilinxfb_of_remove(struct platform_device
*op
)
481 return xilinxfb_release(&op
->dev
);
484 /* Match table for of_platform binding */
485 static const struct of_device_id xilinxfb_of_match
[] = {
486 { .compatible
= "xlnx,xps-tft-1.00.a", },
487 { .compatible
= "xlnx,xps-tft-2.00.a", },
488 { .compatible
= "xlnx,xps-tft-2.01.a", },
489 { .compatible
= "xlnx,plb-tft-cntlr-ref-1.00.a", },
490 { .compatible
= "xlnx,plb-dvi-cntlr-ref-1.00.c", },
493 MODULE_DEVICE_TABLE(of
, xilinxfb_of_match
);
495 static struct platform_driver xilinxfb_of_driver
= {
496 .probe
= xilinxfb_of_probe
,
497 .remove
= xilinxfb_of_remove
,
500 .of_match_table
= xilinxfb_of_match
,
504 module_platform_driver(xilinxfb_of_driver
);
506 MODULE_AUTHOR("MontaVista Software, Inc. <source@mvista.com>");
507 MODULE_DESCRIPTION("Xilinx TFT frame buffer driver");
508 MODULE_LICENSE("GPL");