1287 lines · c
1/*2 * SGI GBE frame buffer driver3 *4 * Copyright (C) 1999 Silicon Graphics, Inc. - Jeffrey Newquist5 * Copyright (C) 2002 Vivien Chappelier <vivien.chappelier@linux-mips.org>6 *7 * This file is subject to the terms and conditions of the GNU General Public8 * License. See the file COPYING in the main directory of this archive for9 * more details.10 */11 12#include <linux/delay.h>13#include <linux/platform_device.h>14#include <linux/dma-mapping.h>15#include <linux/errno.h>16#include <linux/gfp.h>17#include <linux/fb.h>18#include <linux/init.h>19#include <linux/interrupt.h>20#include <linux/kernel.h>21#include <linux/mm.h>22#include <linux/module.h>23#include <linux/io.h>24 25#ifdef CONFIG_MIPS26#include <asm/addrspace.h>27#endif28#include <asm/byteorder.h>29#include <asm/tlbflush.h>30 31#include <video/gbe.h>32 33static struct sgi_gbe *gbe;34 35struct gbefb_par {36 struct fb_var_screeninfo var;37 struct gbe_timing_info timing;38 int wc_cookie;39 int valid;40};41 42#define GBE_BASE 0x16000000 /* SGI O2 */43 44/* macro for fastest write-though access to the framebuffer */45#ifdef CONFIG_MIPS46#ifdef CONFIG_CPU_R1000047#define pgprot_fb(_prot) (((_prot) & (~_CACHE_MASK)) | _CACHE_UNCACHED_ACCELERATED)48#else49#define pgprot_fb(_prot) (((_prot) & (~_CACHE_MASK)) | _CACHE_CACHABLE_NO_WA)50#endif51#endif52 53/*54 * RAM we reserve for the frame buffer. This defines the maximum screen55 * size56 */57#if CONFIG_FB_GBE_MEM > 858#error GBE Framebuffer cannot use more than 8MB of memory59#endif60 61#define TILE_SHIFT 1662#define TILE_SIZE (1 << TILE_SHIFT)63#define TILE_MASK (TILE_SIZE - 1)64 65static unsigned int gbe_mem_size = CONFIG_FB_GBE_MEM * 1024*1024;66static void *gbe_mem;67static dma_addr_t gbe_dma_addr;68static unsigned long gbe_mem_phys;69 70static struct {71 uint16_t *cpu;72 dma_addr_t dma;73} gbe_tiles;74 75static int gbe_revision;76 77static int ypan, ywrap;78 79static uint32_t pseudo_palette[16];80static uint32_t gbe_cmap[256];81static int gbe_turned_on; /* 0 turned off, 1 turned on */82 83static char *mode_option = NULL;84 85/* default CRT mode */86static struct fb_var_screeninfo default_var_CRT = {87 /* 640x480, 60 Hz, Non-Interlaced (25.175 MHz dotclock) */88 .xres = 640,89 .yres = 480,90 .xres_virtual = 640,91 .yres_virtual = 480,92 .xoffset = 0,93 .yoffset = 0,94 .bits_per_pixel = 8,95 .grayscale = 0,96 .red = { 0, 8, 0 },97 .green = { 0, 8, 0 },98 .blue = { 0, 8, 0 },99 .transp = { 0, 0, 0 },100 .nonstd = 0,101 .activate = 0,102 .height = -1,103 .width = -1,104 .accel_flags = 0,105 .pixclock = 39722, /* picoseconds */106 .left_margin = 48,107 .right_margin = 16,108 .upper_margin = 33,109 .lower_margin = 10,110 .hsync_len = 96,111 .vsync_len = 2,112 .sync = 0,113 .vmode = FB_VMODE_NONINTERLACED,114};115 116/* default LCD mode */117static struct fb_var_screeninfo default_var_LCD = {118 /* 1600x1024, 8 bpp */119 .xres = 1600,120 .yres = 1024,121 .xres_virtual = 1600,122 .yres_virtual = 1024,123 .xoffset = 0,124 .yoffset = 0,125 .bits_per_pixel = 8,126 .grayscale = 0,127 .red = { 0, 8, 0 },128 .green = { 0, 8, 0 },129 .blue = { 0, 8, 0 },130 .transp = { 0, 0, 0 },131 .nonstd = 0,132 .activate = 0,133 .height = -1,134 .width = -1,135 .accel_flags = 0,136 .pixclock = 9353,137 .left_margin = 20,138 .right_margin = 30,139 .upper_margin = 37,140 .lower_margin = 3,141 .hsync_len = 20,142 .vsync_len = 3,143 .sync = 0,144 .vmode = FB_VMODE_NONINTERLACED145};146 147/* default modedb mode */148/* 640x480, 60 Hz, Non-Interlaced (25.172 MHz dotclock) */149static struct fb_videomode default_mode_CRT = {150 .refresh = 60,151 .xres = 640,152 .yres = 480,153 .pixclock = 39722,154 .left_margin = 48,155 .right_margin = 16,156 .upper_margin = 33,157 .lower_margin = 10,158 .hsync_len = 96,159 .vsync_len = 2,160 .sync = 0,161 .vmode = FB_VMODE_NONINTERLACED,162};163/* 1600x1024 SGI flatpanel 1600sw */164static struct fb_videomode default_mode_LCD = {165 /* 1600x1024, 8 bpp */166 .xres = 1600,167 .yres = 1024,168 .pixclock = 9353,169 .left_margin = 20,170 .right_margin = 30,171 .upper_margin = 37,172 .lower_margin = 3,173 .hsync_len = 20,174 .vsync_len = 3,175 .vmode = FB_VMODE_NONINTERLACED,176};177 178static struct fb_videomode *default_mode = &default_mode_CRT;179static struct fb_var_screeninfo *default_var = &default_var_CRT;180 181static int flat_panel_enabled = 0;182 183static void gbe_reset(void)184{185 /* Turn on dotclock PLL */186 gbe->ctrlstat = 0x300aa000;187}188 189 190/*191 * Function: gbe_turn_off192 * Parameters: (None)193 * Description: This should turn off the monitor and gbe. This is used194 * when switching between the serial console and the graphics195 * console.196 */197 198static void gbe_turn_off(void)199{200 int i;201 unsigned int val, y, vpixen_off;202 203 gbe_turned_on = 0;204 205 /* check if pixel counter is on */206 val = gbe->vt_xy;207 if (GET_GBE_FIELD(VT_XY, FREEZE, val) == 1)208 return;209 210 /* turn off DMA */211 val = gbe->ovr_control;212 SET_GBE_FIELD(OVR_CONTROL, OVR_DMA_ENABLE, val, 0);213 gbe->ovr_control = val;214 udelay(1000);215 val = gbe->frm_control;216 SET_GBE_FIELD(FRM_CONTROL, FRM_DMA_ENABLE, val, 0);217 gbe->frm_control = val;218 udelay(1000);219 val = gbe->did_control;220 SET_GBE_FIELD(DID_CONTROL, DID_DMA_ENABLE, val, 0);221 gbe->did_control = val;222 udelay(1000);223 224 /* We have to wait through two vertical retrace periods before225 * the pixel DMA is turned off for sure. */226 for (i = 0; i < 10000; i++) {227 val = gbe->frm_inhwctrl;228 if (GET_GBE_FIELD(FRM_INHWCTRL, FRM_DMA_ENABLE, val)) {229 udelay(10);230 } else {231 val = gbe->ovr_inhwctrl;232 if (GET_GBE_FIELD(OVR_INHWCTRL, OVR_DMA_ENABLE, val)) {233 udelay(10);234 } else {235 val = gbe->did_inhwctrl;236 if (GET_GBE_FIELD(DID_INHWCTRL, DID_DMA_ENABLE, val)) {237 udelay(10);238 } else239 break;240 }241 }242 }243 if (i == 10000)244 printk(KERN_ERR "gbefb: turn off DMA timed out\n");245 246 /* wait for vpixen_off */247 val = gbe->vt_vpixen;248 vpixen_off = GET_GBE_FIELD(VT_VPIXEN, VPIXEN_OFF, val);249 250 for (i = 0; i < 100000; i++) {251 val = gbe->vt_xy;252 y = GET_GBE_FIELD(VT_XY, Y, val);253 if (y < vpixen_off)254 break;255 udelay(1);256 }257 if (i == 100000)258 printk(KERN_ERR259 "gbefb: wait for vpixen_off timed out\n");260 for (i = 0; i < 10000; i++) {261 val = gbe->vt_xy;262 y = GET_GBE_FIELD(VT_XY, Y, val);263 if (y > vpixen_off)264 break;265 udelay(1);266 }267 if (i == 10000)268 printk(KERN_ERR "gbefb: wait for vpixen_off timed out\n");269 270 /* turn off pixel counter */271 val = 0;272 SET_GBE_FIELD(VT_XY, FREEZE, val, 1);273 gbe->vt_xy = val;274 mdelay(10);275 for (i = 0; i < 10000; i++) {276 val = gbe->vt_xy;277 if (GET_GBE_FIELD(VT_XY, FREEZE, val) != 1)278 udelay(10);279 else280 break;281 }282 if (i == 10000)283 printk(KERN_ERR "gbefb: turn off pixel clock timed out\n");284 285 /* turn off dot clock */286 val = gbe->dotclock;287 SET_GBE_FIELD(DOTCLK, RUN, val, 0);288 gbe->dotclock = val;289 mdelay(10);290 for (i = 0; i < 10000; i++) {291 val = gbe->dotclock;292 if (GET_GBE_FIELD(DOTCLK, RUN, val))293 udelay(10);294 else295 break;296 }297 if (i == 10000)298 printk(KERN_ERR "gbefb: turn off dotclock timed out\n");299 300 /* reset the frame DMA FIFO */301 val = gbe->frm_size_tile;302 SET_GBE_FIELD(FRM_SIZE_TILE, FRM_FIFO_RESET, val, 1);303 gbe->frm_size_tile = val;304 SET_GBE_FIELD(FRM_SIZE_TILE, FRM_FIFO_RESET, val, 0);305 gbe->frm_size_tile = val;306}307 308static void gbe_turn_on(void)309{310 unsigned int val, i;311 312 /*313 * Check if pixel counter is off, for unknown reason this314 * code hangs Visual Workstations315 */316 if (gbe_revision < 2) {317 val = gbe->vt_xy;318 if (GET_GBE_FIELD(VT_XY, FREEZE, val) == 0)319 return;320 }321 322 /* turn on dot clock */323 val = gbe->dotclock;324 SET_GBE_FIELD(DOTCLK, RUN, val, 1);325 gbe->dotclock = val;326 mdelay(10);327 for (i = 0; i < 10000; i++) {328 val = gbe->dotclock;329 if (GET_GBE_FIELD(DOTCLK, RUN, val) != 1)330 udelay(10);331 else332 break;333 }334 if (i == 10000)335 printk(KERN_ERR "gbefb: turn on dotclock timed out\n");336 337 /* turn on pixel counter */338 val = 0;339 SET_GBE_FIELD(VT_XY, FREEZE, val, 0);340 gbe->vt_xy = val;341 mdelay(10);342 for (i = 0; i < 10000; i++) {343 val = gbe->vt_xy;344 if (GET_GBE_FIELD(VT_XY, FREEZE, val))345 udelay(10);346 else347 break;348 }349 if (i == 10000)350 printk(KERN_ERR "gbefb: turn on pixel clock timed out\n");351 352 /* turn on DMA */353 val = gbe->frm_control;354 SET_GBE_FIELD(FRM_CONTROL, FRM_DMA_ENABLE, val, 1);355 gbe->frm_control = val;356 udelay(1000);357 for (i = 0; i < 10000; i++) {358 val = gbe->frm_inhwctrl;359 if (GET_GBE_FIELD(FRM_INHWCTRL, FRM_DMA_ENABLE, val) != 1)360 udelay(10);361 else362 break;363 }364 if (i == 10000)365 printk(KERN_ERR "gbefb: turn on DMA timed out\n");366 367 gbe_turned_on = 1;368}369 370static void gbe_loadcmap(void)371{372 int i, j;373 374 for (i = 0; i < 256; i++) {375 for (j = 0; j < 1000 && gbe->cm_fifo >= 63; j++)376 udelay(10);377 if (j == 1000)378 printk(KERN_ERR "gbefb: cmap FIFO timeout\n");379 380 gbe->cmap[i] = gbe_cmap[i];381 }382}383 384/*385 * Blank the display.386 */387static int gbefb_blank(int blank, struct fb_info *info)388{389 /* 0 unblank, 1 blank, 2 no vsync, 3 no hsync, 4 off */390 switch (blank) {391 case FB_BLANK_UNBLANK: /* unblank */392 gbe_turn_on();393 gbe_loadcmap();394 break;395 396 case FB_BLANK_NORMAL: /* blank */397 gbe_turn_off();398 break;399 400 default:401 /* Nothing */402 break;403 }404 return 0;405}406 407/*408 * Setup flatpanel related registers.409 */410static void gbefb_setup_flatpanel(struct gbe_timing_info *timing)411{412 int fp_wid, fp_hgt, fp_vbs, fp_vbe;413 u32 outputVal = 0;414 415 SET_GBE_FIELD(VT_FLAGS, HDRV_INVERT, outputVal,416 (timing->flags & FB_SYNC_HOR_HIGH_ACT) ? 0 : 1);417 SET_GBE_FIELD(VT_FLAGS, VDRV_INVERT, outputVal,418 (timing->flags & FB_SYNC_VERT_HIGH_ACT) ? 0 : 1);419 gbe->vt_flags = outputVal;420 421 /* Turn on the flat panel */422 fp_wid = 1600;423 fp_hgt = 1024;424 fp_vbs = 0;425 fp_vbe = 1600;426 timing->pll_m = 4;427 timing->pll_n = 1;428 timing->pll_p = 0;429 430 outputVal = 0;431 SET_GBE_FIELD(FP_DE, ON, outputVal, fp_vbs);432 SET_GBE_FIELD(FP_DE, OFF, outputVal, fp_vbe);433 gbe->fp_de = outputVal;434 outputVal = 0;435 SET_GBE_FIELD(FP_HDRV, OFF, outputVal, fp_wid);436 gbe->fp_hdrv = outputVal;437 outputVal = 0;438 SET_GBE_FIELD(FP_VDRV, ON, outputVal, 1);439 SET_GBE_FIELD(FP_VDRV, OFF, outputVal, fp_hgt + 1);440 gbe->fp_vdrv = outputVal;441}442 443struct gbe_pll_info {444 int clock_rate;445 int fvco_min;446 int fvco_max;447};448 449static struct gbe_pll_info gbe_pll_table[2] = {450 { 20, 80, 220 },451 { 27, 80, 220 },452};453 454static int compute_gbe_timing(struct fb_var_screeninfo *var,455 struct gbe_timing_info *timing)456{457 int pll_m, pll_n, pll_p, error, best_m, best_n, best_p, best_error;458 int pixclock;459 struct gbe_pll_info *gbe_pll;460 461 if (gbe_revision < 2)462 gbe_pll = &gbe_pll_table[0];463 else464 gbe_pll = &gbe_pll_table[1];465 466 /* Determine valid resolution and timing467 * GBE crystal runs at 20Mhz or 27Mhz468 * pll_m, pll_n, pll_p define the following frequencies469 * fvco = pll_m * 20Mhz / pll_n470 * fout = fvco / (2**pll_p) */471 best_error = 1000000000;472 best_n = best_m = best_p = 0;473 for (pll_p = 0; pll_p < 4; pll_p++)474 for (pll_m = 1; pll_m < 256; pll_m++)475 for (pll_n = 1; pll_n < 64; pll_n++) {476 pixclock = (1000000 / gbe_pll->clock_rate) *477 (pll_n << pll_p) / pll_m;478 479 error = var->pixclock - pixclock;480 481 if (error < 0)482 error = -error;483 484 if (error < best_error &&485 pll_m / pll_n >486 gbe_pll->fvco_min / gbe_pll->clock_rate &&487 pll_m / pll_n <488 gbe_pll->fvco_max / gbe_pll->clock_rate) {489 best_error = error;490 best_m = pll_m;491 best_n = pll_n;492 best_p = pll_p;493 }494 }495 496 if (!best_n || !best_m)497 return -EINVAL; /* Resolution to high */498 499 pixclock = (1000000 / gbe_pll->clock_rate) *500 (best_n << best_p) / best_m;501 502 /* set video timing information */503 if (timing) {504 timing->width = var->xres;505 timing->height = var->yres;506 timing->pll_m = best_m;507 timing->pll_n = best_n;508 timing->pll_p = best_p;509 timing->cfreq = gbe_pll->clock_rate * 1000 * timing->pll_m /510 (timing->pll_n << timing->pll_p);511 timing->htotal = var->left_margin + var->xres +512 var->right_margin + var->hsync_len;513 timing->vtotal = var->upper_margin + var->yres +514 var->lower_margin + var->vsync_len;515 timing->fields_sec = 1000 * timing->cfreq / timing->htotal *516 1000 / timing->vtotal;517 timing->hblank_start = var->xres;518 timing->vblank_start = var->yres;519 timing->hblank_end = timing->htotal;520 timing->hsync_start = var->xres + var->right_margin + 1;521 timing->hsync_end = timing->hsync_start + var->hsync_len;522 timing->vblank_end = timing->vtotal;523 timing->vsync_start = var->yres + var->lower_margin + 1;524 timing->vsync_end = timing->vsync_start + var->vsync_len;525 }526 527 return pixclock;528}529 530static void gbe_set_timing_info(struct gbe_timing_info *timing)531{532 int temp;533 unsigned int val;534 535 /* setup dot clock PLL */536 val = 0;537 SET_GBE_FIELD(DOTCLK, M, val, timing->pll_m - 1);538 SET_GBE_FIELD(DOTCLK, N, val, timing->pll_n - 1);539 SET_GBE_FIELD(DOTCLK, P, val, timing->pll_p);540 SET_GBE_FIELD(DOTCLK, RUN, val, 0); /* do not start yet */541 gbe->dotclock = val;542 mdelay(10);543 544 /* setup pixel counter */545 val = 0;546 SET_GBE_FIELD(VT_XYMAX, MAXX, val, timing->htotal);547 SET_GBE_FIELD(VT_XYMAX, MAXY, val, timing->vtotal);548 gbe->vt_xymax = val;549 550 /* setup video timing signals */551 val = 0;552 SET_GBE_FIELD(VT_VSYNC, VSYNC_ON, val, timing->vsync_start);553 SET_GBE_FIELD(VT_VSYNC, VSYNC_OFF, val, timing->vsync_end);554 gbe->vt_vsync = val;555 val = 0;556 SET_GBE_FIELD(VT_HSYNC, HSYNC_ON, val, timing->hsync_start);557 SET_GBE_FIELD(VT_HSYNC, HSYNC_OFF, val, timing->hsync_end);558 gbe->vt_hsync = val;559 val = 0;560 SET_GBE_FIELD(VT_VBLANK, VBLANK_ON, val, timing->vblank_start);561 SET_GBE_FIELD(VT_VBLANK, VBLANK_OFF, val, timing->vblank_end);562 gbe->vt_vblank = val;563 val = 0;564 SET_GBE_FIELD(VT_HBLANK, HBLANK_ON, val,565 timing->hblank_start - 5);566 SET_GBE_FIELD(VT_HBLANK, HBLANK_OFF, val,567 timing->hblank_end - 3);568 gbe->vt_hblank = val;569 570 /* setup internal timing signals */571 val = 0;572 SET_GBE_FIELD(VT_VCMAP, VCMAP_ON, val, timing->vblank_start);573 SET_GBE_FIELD(VT_VCMAP, VCMAP_OFF, val, timing->vblank_end);574 gbe->vt_vcmap = val;575 val = 0;576 SET_GBE_FIELD(VT_HCMAP, HCMAP_ON, val, timing->hblank_start);577 SET_GBE_FIELD(VT_HCMAP, HCMAP_OFF, val, timing->hblank_end);578 gbe->vt_hcmap = val;579 580 val = 0;581 temp = timing->vblank_start - timing->vblank_end - 1;582 if (temp > 0)583 temp = -temp;584 585 if (flat_panel_enabled)586 gbefb_setup_flatpanel(timing);587 588 SET_GBE_FIELD(DID_START_XY, DID_STARTY, val, (u32) temp);589 if (timing->hblank_end >= 20)590 SET_GBE_FIELD(DID_START_XY, DID_STARTX, val,591 timing->hblank_end - 20);592 else593 SET_GBE_FIELD(DID_START_XY, DID_STARTX, val,594 timing->htotal - (20 - timing->hblank_end));595 gbe->did_start_xy = val;596 597 val = 0;598 SET_GBE_FIELD(CRS_START_XY, CRS_STARTY, val, (u32) (temp + 1));599 if (timing->hblank_end >= GBE_CRS_MAGIC)600 SET_GBE_FIELD(CRS_START_XY, CRS_STARTX, val,601 timing->hblank_end - GBE_CRS_MAGIC);602 else603 SET_GBE_FIELD(CRS_START_XY, CRS_STARTX, val,604 timing->htotal - (GBE_CRS_MAGIC -605 timing->hblank_end));606 gbe->crs_start_xy = val;607 608 val = 0;609 SET_GBE_FIELD(VC_START_XY, VC_STARTY, val, (u32) temp);610 SET_GBE_FIELD(VC_START_XY, VC_STARTX, val, timing->hblank_end - 4);611 gbe->vc_start_xy = val;612 613 val = 0;614 temp = timing->hblank_end - GBE_PIXEN_MAGIC_ON;615 if (temp < 0)616 temp += timing->htotal; /* allow blank to wrap around */617 618 SET_GBE_FIELD(VT_HPIXEN, HPIXEN_ON, val, temp);619 SET_GBE_FIELD(VT_HPIXEN, HPIXEN_OFF, val,620 ((temp + timing->width -621 GBE_PIXEN_MAGIC_OFF) % timing->htotal));622 gbe->vt_hpixen = val;623 624 val = 0;625 SET_GBE_FIELD(VT_VPIXEN, VPIXEN_ON, val, timing->vblank_end);626 SET_GBE_FIELD(VT_VPIXEN, VPIXEN_OFF, val, timing->vblank_start);627 gbe->vt_vpixen = val;628 629 /* turn off sync on green */630 val = 0;631 SET_GBE_FIELD(VT_FLAGS, SYNC_LOW, val, 1);632 gbe->vt_flags = val;633}634 635/*636 * Set the hardware according to 'par'.637 */638 639static int gbefb_set_par(struct fb_info *info)640{641 int i;642 unsigned int val;643 int wholeTilesX, partTilesX, maxPixelsPerTileX;644 int height_pix;645 int xpmax, ypmax; /* Monitor resolution */646 int bytesPerPixel; /* Bytes per pixel */647 struct gbefb_par *par = (struct gbefb_par *) info->par;648 649 compute_gbe_timing(&info->var, &par->timing);650 651 bytesPerPixel = info->var.bits_per_pixel / 8;652 info->fix.line_length = info->var.xres_virtual * bytesPerPixel;653 xpmax = par->timing.width;654 ypmax = par->timing.height;655 656 /* turn off GBE */657 gbe_turn_off();658 659 /* set timing info */660 gbe_set_timing_info(&par->timing);661 662 /* initialize DIDs */663 val = 0;664 switch (bytesPerPixel) {665 case 1:666 SET_GBE_FIELD(WID, TYP, val, GBE_CMODE_I8);667 info->fix.visual = FB_VISUAL_PSEUDOCOLOR;668 break;669 case 2:670 SET_GBE_FIELD(WID, TYP, val, GBE_CMODE_ARGB5);671 info->fix.visual = FB_VISUAL_TRUECOLOR;672 break;673 case 4:674 SET_GBE_FIELD(WID, TYP, val, GBE_CMODE_RGB8);675 info->fix.visual = FB_VISUAL_TRUECOLOR;676 break;677 }678 SET_GBE_FIELD(WID, BUF, val, GBE_BMODE_BOTH);679 680 for (i = 0; i < 32; i++)681 gbe->mode_regs[i] = val;682 683 /* Initialize interrupts */684 gbe->vt_intr01 = 0xffffffff;685 gbe->vt_intr23 = 0xffffffff;686 687 /* HACK:688 The GBE hardware uses a tiled memory to screen mapping. Tiles are689 blocks of 512x128, 256x128 or 128x128 pixels, respectively for 8bit,690 16bit and 32 bit modes (64 kB). They cover the screen with partial691 tiles on the right and/or bottom of the screen if needed.692 For example in 640x480 8 bit mode the mapping is:693 694 <-------- 640 ----->695 <---- 512 ----><128|384 offscreen>696 ^ ^697 | 128 [tile 0] [tile 1]698 | v699 ^700 4 128 [tile 2] [tile 3]701 8 v702 0 ^703 128 [tile 4] [tile 5]704 | v705 | ^706 v 96 [tile 6] [tile 7]707 32 offscreen708 709 Tiles have the advantage that they can be allocated individually in710 memory. However, this mapping is not linear at all, which is not711 really convenient. In order to support linear addressing, the GBE712 DMA hardware is fooled into thinking the screen is only one tile713 large and but has a greater height, so that the DMA transfer covers714 the same region.715 Tiles are still allocated as independent chunks of 64KB of716 continuous physical memory and remapped so that the kernel sees the717 framebuffer as a continuous virtual memory. The GBE tile table is718 set up so that each tile references one of these 64k blocks:719 720 GBE -> tile list framebuffer TLB <------------ CPU721 [ tile 0 ] -> [ 64KB ] <- [ 16x 4KB page entries ] ^722 ... ... ... linear virtual FB723 [ tile n ] -> [ 64KB ] <- [ 16x 4KB page entries ] v724 725 726 The GBE hardware is then told that the buffer is 512*tweaked_height,727 with tweaked_height = real_width*real_height/pixels_per_tile.728 Thus the GBE hardware will scan the first tile, filing the first 64k729 covered region of the screen, and then will proceed to the next730 tile, until the whole screen is covered.731 732 Here is what would happen at 640x480 8bit:733 734 normal tiling linear735 ^ 11111111111111112222 11111111111111111111 ^736 128 11111111111111112222 11111111111111111111 102 lines737 11111111111111112222 11111111111111111111 v738 V 11111111111111112222 11111111222222222222739 33333333333333334444 22222222222222222222740 33333333333333334444 22222222222222222222741 < 512 > < 256 > 102*640+256 = 64k742 743 NOTE: The only mode for which this is not working is 800x600 8bit,744 as 800*600/512 = 937.5 which is not integer and thus causes745 flickering.746 I guess this is not so important as one can use 640x480 8bit or747 800x600 16bit anyway.748 */749 750 /* Tell gbe about the tiles table location */751 /* tile_ptr -> [ tile 1 ] -> FB mem */752 /* [ tile 2 ] -> FB mem */753 /* ... */754 val = 0;755 SET_GBE_FIELD(FRM_CONTROL, FRM_TILE_PTR, val, gbe_tiles.dma >> 9);756 SET_GBE_FIELD(FRM_CONTROL, FRM_DMA_ENABLE, val, 0); /* do not start */757 SET_GBE_FIELD(FRM_CONTROL, FRM_LINEAR, val, 0);758 gbe->frm_control = val;759 760 maxPixelsPerTileX = 512 / bytesPerPixel;761 wholeTilesX = 1;762 partTilesX = 0;763 764 /* Initialize the framebuffer */765 val = 0;766 SET_GBE_FIELD(FRM_SIZE_TILE, FRM_WIDTH_TILE, val, wholeTilesX);767 SET_GBE_FIELD(FRM_SIZE_TILE, FRM_RHS, val, partTilesX);768 769 switch (bytesPerPixel) {770 case 1:771 SET_GBE_FIELD(FRM_SIZE_TILE, FRM_DEPTH, val,772 GBE_FRM_DEPTH_8);773 break;774 case 2:775 SET_GBE_FIELD(FRM_SIZE_TILE, FRM_DEPTH, val,776 GBE_FRM_DEPTH_16);777 break;778 case 4:779 SET_GBE_FIELD(FRM_SIZE_TILE, FRM_DEPTH, val,780 GBE_FRM_DEPTH_32);781 break;782 }783 gbe->frm_size_tile = val;784 785 /* compute tweaked height */786 height_pix = xpmax * ypmax / maxPixelsPerTileX;787 788 val = 0;789 SET_GBE_FIELD(FRM_SIZE_PIXEL, FB_HEIGHT_PIX, val, height_pix);790 gbe->frm_size_pixel = val;791 792 /* turn off DID and overlay DMA */793 gbe->did_control = 0;794 gbe->ovr_width_tile = 0;795 796 /* Turn off mouse cursor */797 gbe->crs_ctl = 0;798 799 /* Turn on GBE */800 gbe_turn_on();801 802 /* Initialize the gamma map */803 udelay(10);804 for (i = 0; i < 256; i++)805 gbe->gmap[i] = (i << 24) | (i << 16) | (i << 8);806 807 /* Initialize the color map */808 for (i = 0; i < 256; i++)809 gbe_cmap[i] = (i << 8) | (i << 16) | (i << 24);810 811 gbe_loadcmap();812 813 return 0;814}815 816static void gbefb_encode_fix(struct fb_fix_screeninfo *fix,817 struct fb_var_screeninfo *var)818{819 memset(fix, 0, sizeof(struct fb_fix_screeninfo));820 strcpy(fix->id, "SGI GBE");821 fix->smem_start = (unsigned long) gbe_mem;822 fix->smem_len = gbe_mem_size;823 fix->type = FB_TYPE_PACKED_PIXELS;824 fix->type_aux = 0;825 fix->accel = FB_ACCEL_NONE;826 switch (var->bits_per_pixel) {827 case 8:828 fix->visual = FB_VISUAL_PSEUDOCOLOR;829 break;830 default:831 fix->visual = FB_VISUAL_TRUECOLOR;832 break;833 }834 fix->ywrapstep = 0;835 fix->xpanstep = 0;836 fix->ypanstep = 0;837 fix->line_length = var->xres_virtual * var->bits_per_pixel / 8;838 fix->mmio_start = GBE_BASE;839 fix->mmio_len = sizeof(struct sgi_gbe);840}841 842/*843 * Set a single color register. The values supplied are already844 * rounded down to the hardware's capabilities (according to the845 * entries in the var structure). Return != 0 for invalid regno.846 */847 848static int gbefb_setcolreg(unsigned regno, unsigned red, unsigned green,849 unsigned blue, unsigned transp,850 struct fb_info *info)851{852 int i;853 854 if (regno > 255)855 return 1;856 red >>= 8;857 green >>= 8;858 blue >>= 8;859 860 if (info->var.bits_per_pixel <= 8) {861 gbe_cmap[regno] = (red << 24) | (green << 16) | (blue << 8);862 if (gbe_turned_on) {863 /* wait for the color map FIFO to have a free entry */864 for (i = 0; i < 1000 && gbe->cm_fifo >= 63; i++)865 udelay(10);866 if (i == 1000) {867 printk(KERN_ERR "gbefb: cmap FIFO timeout\n");868 return 1;869 }870 gbe->cmap[regno] = gbe_cmap[regno];871 }872 } else if (regno < 16) {873 switch (info->var.bits_per_pixel) {874 case 15:875 case 16:876 red >>= 3;877 green >>= 3;878 blue >>= 3;879 pseudo_palette[regno] =880 (red << info->var.red.offset) |881 (green << info->var.green.offset) |882 (blue << info->var.blue.offset);883 break;884 case 32:885 pseudo_palette[regno] =886 (red << info->var.red.offset) |887 (green << info->var.green.offset) |888 (blue << info->var.blue.offset);889 break;890 }891 }892 893 return 0;894}895 896/*897 * Check video mode validity, eventually modify var to best match.898 */899static int gbefb_check_var(struct fb_var_screeninfo *var, struct fb_info *info)900{901 unsigned int line_length;902 struct gbe_timing_info timing;903 int ret;904 905 /* Limit bpp to 8, 16, and 32 */906 if (var->bits_per_pixel <= 8)907 var->bits_per_pixel = 8;908 else if (var->bits_per_pixel <= 16)909 var->bits_per_pixel = 16;910 else if (var->bits_per_pixel <= 32)911 var->bits_per_pixel = 32;912 else913 return -EINVAL;914 915 /* Check the mode can be mapped linearly with the tile table trick. */916 /* This requires width x height x bytes/pixel be a multiple of 512 */917 if ((var->xres * var->yres * var->bits_per_pixel) & 4095)918 return -EINVAL;919 920 var->grayscale = 0; /* No grayscale for now */921 922 ret = compute_gbe_timing(var, &timing);923 var->pixclock = ret;924 if (ret < 0)925 return -EINVAL;926 927 /* Adjust virtual resolution, if necessary */928 if (var->xres > var->xres_virtual || (!ywrap && !ypan))929 var->xres_virtual = var->xres;930 if (var->yres > var->yres_virtual || (!ywrap && !ypan))931 var->yres_virtual = var->yres;932 933 if (var->vmode & FB_VMODE_CONUPDATE) {934 var->vmode |= FB_VMODE_YWRAP;935 var->xoffset = info->var.xoffset;936 var->yoffset = info->var.yoffset;937 }938 939 /* No grayscale for now */940 var->grayscale = 0;941 942 /* Memory limit */943 line_length = var->xres_virtual * var->bits_per_pixel / 8;944 if (line_length * var->yres_virtual > gbe_mem_size)945 return -ENOMEM; /* Virtual resolution too high */946 947 switch (var->bits_per_pixel) {948 case 8:949 var->red.offset = 0;950 var->red.length = 8;951 var->green.offset = 0;952 var->green.length = 8;953 var->blue.offset = 0;954 var->blue.length = 8;955 var->transp.offset = 0;956 var->transp.length = 0;957 break;958 case 16: /* RGB 1555 */959 var->red.offset = 10;960 var->red.length = 5;961 var->green.offset = 5;962 var->green.length = 5;963 var->blue.offset = 0;964 var->blue.length = 5;965 var->transp.offset = 0;966 var->transp.length = 0;967 break;968 case 32: /* RGB 8888 */969 var->red.offset = 24;970 var->red.length = 8;971 var->green.offset = 16;972 var->green.length = 8;973 var->blue.offset = 8;974 var->blue.length = 8;975 var->transp.offset = 0;976 var->transp.length = 8;977 break;978 }979 var->red.msb_right = 0;980 var->green.msb_right = 0;981 var->blue.msb_right = 0;982 var->transp.msb_right = 0;983 984 var->left_margin = timing.htotal - timing.hsync_end;985 var->right_margin = timing.hsync_start - timing.width;986 var->upper_margin = timing.vtotal - timing.vsync_end;987 var->lower_margin = timing.vsync_start - timing.height;988 var->hsync_len = timing.hsync_end - timing.hsync_start;989 var->vsync_len = timing.vsync_end - timing.vsync_start;990 991 return 0;992}993 994static int gbefb_mmap(struct fb_info *info,995 struct vm_area_struct *vma)996{997 unsigned long size = vma->vm_end - vma->vm_start;998 unsigned long offset = vma->vm_pgoff << PAGE_SHIFT;999 unsigned long addr;1000 unsigned long phys_addr, phys_size;1001 u16 *tile;1002 1003 vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot);1004 1005 /* check range */1006 if (vma->vm_pgoff > (~0UL >> PAGE_SHIFT))1007 return -EINVAL;1008 if (size > gbe_mem_size)1009 return -EINVAL;1010 if (offset > gbe_mem_size - size)1011 return -EINVAL;1012 1013 /* remap using the fastest write-through mode on architecture */1014 /* try not polluting the cache when possible */1015#ifdef CONFIG_MIPS1016 pgprot_val(vma->vm_page_prot) =1017 pgprot_fb(pgprot_val(vma->vm_page_prot));1018#endif1019 /* VM_IO | VM_DONTEXPAND | VM_DONTDUMP are set by remap_pfn_range() */1020 1021 /* look for the starting tile */1022 tile = &gbe_tiles.cpu[offset >> TILE_SHIFT];1023 addr = vma->vm_start;1024 offset &= TILE_MASK;1025 1026 /* remap each tile separately */1027 do {1028 phys_addr = (((unsigned long) (*tile)) << TILE_SHIFT) + offset;1029 if ((offset + size) < TILE_SIZE)1030 phys_size = size;1031 else1032 phys_size = TILE_SIZE - offset;1033 1034 if (remap_pfn_range(vma, addr, phys_addr >> PAGE_SHIFT,1035 phys_size, vma->vm_page_prot))1036 return -EAGAIN;1037 1038 offset = 0;1039 size -= phys_size;1040 addr += phys_size;1041 tile++;1042 } while (size);1043 1044 return 0;1045}1046 1047static const struct fb_ops gbefb_ops = {1048 .owner = THIS_MODULE,1049 __FB_DEFAULT_IOMEM_OPS_RDWR,1050 .fb_check_var = gbefb_check_var,1051 .fb_set_par = gbefb_set_par,1052 .fb_setcolreg = gbefb_setcolreg,1053 .fb_blank = gbefb_blank,1054 __FB_DEFAULT_IOMEM_OPS_DRAW,1055 .fb_mmap = gbefb_mmap,1056};1057 1058/*1059 * sysfs1060 */1061 1062static ssize_t gbefb_show_memsize(struct device *dev, struct device_attribute *attr, char *buf)1063{1064 return sysfs_emit(buf, "%u\n", gbe_mem_size);1065}1066 1067static DEVICE_ATTR(size, S_IRUGO, gbefb_show_memsize, NULL);1068 1069static ssize_t gbefb_show_rev(struct device *device, struct device_attribute *attr, char *buf)1070{1071 return sysfs_emit(buf, "%d\n", gbe_revision);1072}1073 1074static DEVICE_ATTR(revision, S_IRUGO, gbefb_show_rev, NULL);1075 1076static struct attribute *gbefb_attrs[] = {1077 &dev_attr_size.attr,1078 &dev_attr_revision.attr,1079 NULL,1080};1081ATTRIBUTE_GROUPS(gbefb);1082 1083/*1084 * Initialization1085 */1086 1087static int gbefb_setup(char *options)1088{1089 char *this_opt;1090 1091 if (!options || !*options)1092 return 0;1093 1094 while ((this_opt = strsep(&options, ",")) != NULL) {1095 if (!strncmp(this_opt, "monitor:", 8)) {1096 if (!strncmp(this_opt + 8, "crt", 3)) {1097 flat_panel_enabled = 0;1098 default_var = &default_var_CRT;1099 default_mode = &default_mode_CRT;1100 } else if (!strncmp(this_opt + 8, "1600sw", 6) ||1101 !strncmp(this_opt + 8, "lcd", 3)) {1102 flat_panel_enabled = 1;1103 default_var = &default_var_LCD;1104 default_mode = &default_mode_LCD;1105 }1106 } else if (!strncmp(this_opt, "mem:", 4)) {1107 gbe_mem_size = memparse(this_opt + 4, &this_opt);1108 if (gbe_mem_size > CONFIG_FB_GBE_MEM * 1024 * 1024)1109 gbe_mem_size = CONFIG_FB_GBE_MEM * 1024 * 1024;1110 if (gbe_mem_size < TILE_SIZE)1111 gbe_mem_size = TILE_SIZE;1112 } else1113 mode_option = this_opt;1114 }1115 return 0;1116}1117 1118static int gbefb_probe(struct platform_device *p_dev)1119{1120 int i, ret = 0;1121 struct fb_info *info;1122 struct gbefb_par *par;1123#ifndef MODULE1124 char *options = NULL;1125#endif1126 1127 info = framebuffer_alloc(sizeof(struct gbefb_par), &p_dev->dev);1128 if (!info)1129 return -ENOMEM;1130 1131#ifndef MODULE1132 if (fb_get_options("gbefb", &options)) {1133 ret = -ENODEV;1134 goto out_release_framebuffer;1135 }1136 gbefb_setup(options);1137#endif1138 1139 if (!request_mem_region(GBE_BASE, sizeof(struct sgi_gbe), "GBE")) {1140 printk(KERN_ERR "gbefb: couldn't reserve mmio region\n");1141 ret = -EBUSY;1142 goto out_release_framebuffer;1143 }1144 1145 gbe = (struct sgi_gbe *) devm_ioremap(&p_dev->dev, GBE_BASE,1146 sizeof(struct sgi_gbe));1147 if (!gbe) {1148 printk(KERN_ERR "gbefb: couldn't map mmio region\n");1149 ret = -ENXIO;1150 goto out_release_mem_region;1151 }1152 gbe_revision = gbe->ctrlstat & 15;1153 1154 gbe_tiles.cpu = dmam_alloc_coherent(&p_dev->dev,1155 GBE_TLB_SIZE * sizeof(uint16_t),1156 &gbe_tiles.dma, GFP_KERNEL);1157 if (!gbe_tiles.cpu) {1158 printk(KERN_ERR "gbefb: couldn't allocate tiles table\n");1159 ret = -ENOMEM;1160 goto out_release_mem_region;1161 }1162 1163 if (gbe_mem_phys) {1164 /* memory was allocated at boot time */1165 gbe_mem = devm_ioremap_wc(&p_dev->dev, gbe_mem_phys,1166 gbe_mem_size);1167 if (!gbe_mem) {1168 printk(KERN_ERR "gbefb: couldn't map framebuffer\n");1169 ret = -ENOMEM;1170 goto out_release_mem_region;1171 }1172 1173 gbe_dma_addr = 0;1174 } else {1175 /* try to allocate memory with the classical allocator1176 * this has high chance to fail on low memory machines */1177 gbe_mem = dmam_alloc_attrs(&p_dev->dev, gbe_mem_size,1178 &gbe_dma_addr, GFP_KERNEL,1179 DMA_ATTR_WRITE_COMBINE);1180 if (!gbe_mem) {1181 printk(KERN_ERR "gbefb: couldn't allocate framebuffer memory\n");1182 ret = -ENOMEM;1183 goto out_release_mem_region;1184 }1185 1186 gbe_mem_phys = (unsigned long) gbe_dma_addr;1187 }1188 1189 par = info->par;1190 par->wc_cookie = arch_phys_wc_add(gbe_mem_phys, gbe_mem_size);1191 1192 /* map framebuffer memory into tiles table */1193 for (i = 0; i < (gbe_mem_size >> TILE_SHIFT); i++)1194 gbe_tiles.cpu[i] = (gbe_mem_phys >> TILE_SHIFT) + i;1195 1196 info->fbops = &gbefb_ops;1197 info->pseudo_palette = pseudo_palette;1198 info->screen_base = gbe_mem;1199 fb_alloc_cmap(&info->cmap, 256, 0);1200 1201 /* reset GBE */1202 gbe_reset();1203 1204 /* turn on default video mode */1205 if (fb_find_mode(&par->var, info, mode_option, NULL, 0,1206 default_mode, 8) == 0)1207 par->var = *default_var;1208 info->var = par->var;1209 gbefb_check_var(&par->var, info);1210 gbefb_encode_fix(&info->fix, &info->var);1211 1212 if (register_framebuffer(info) < 0) {1213 printk(KERN_ERR "gbefb: couldn't register framebuffer\n");1214 ret = -ENXIO;1215 goto out_gbe_unmap;1216 }1217 1218 platform_set_drvdata(p_dev, info);1219 1220 fb_info(info, "%s rev %d @ 0x%08x using %dkB memory\n",1221 info->fix.id, gbe_revision, (unsigned)GBE_BASE,1222 gbe_mem_size >> 10);1223 1224 return 0;1225 1226out_gbe_unmap:1227 arch_phys_wc_del(par->wc_cookie);1228out_release_mem_region:1229 release_mem_region(GBE_BASE, sizeof(struct sgi_gbe));1230out_release_framebuffer:1231 framebuffer_release(info);1232 1233 return ret;1234}1235 1236static void gbefb_remove(struct platform_device* p_dev)1237{1238 struct fb_info *info = platform_get_drvdata(p_dev);1239 struct gbefb_par *par = info->par;1240 1241 unregister_framebuffer(info);1242 gbe_turn_off();1243 arch_phys_wc_del(par->wc_cookie);1244 release_mem_region(GBE_BASE, sizeof(struct sgi_gbe));1245 framebuffer_release(info);1246}1247 1248static struct platform_driver gbefb_driver = {1249 .probe = gbefb_probe,1250 .remove = gbefb_remove,1251 .driver = {1252 .name = "gbefb",1253 .dev_groups = gbefb_groups,1254 },1255};1256 1257static struct platform_device *gbefb_device;1258 1259static int __init gbefb_init(void)1260{1261 int ret = platform_driver_register(&gbefb_driver);1262 if (IS_ENABLED(CONFIG_SGI_IP32) && !ret) {1263 gbefb_device = platform_device_alloc("gbefb", 0);1264 if (gbefb_device) {1265 ret = platform_device_add(gbefb_device);1266 } else {1267 ret = -ENOMEM;1268 }1269 if (ret) {1270 platform_device_put(gbefb_device);1271 platform_driver_unregister(&gbefb_driver);1272 }1273 }1274 return ret;1275}1276 1277static void __exit gbefb_exit(void)1278{1279 platform_device_unregister(gbefb_device);1280 platform_driver_unregister(&gbefb_driver);1281}1282 1283module_init(gbefb_init);1284module_exit(gbefb_exit);1285 1286MODULE_LICENSE("GPL");1287