drivers/gpu/drm/nouveau/dispnv04/arb.c

   1 /*
   2  * Copyright 1993-2003 NVIDIA, Corporation
   3  * Copyright 2007-2009 Stuart Bennett
   4  *
   5  * Permission is hereby granted, free of charge, to any person obtaining a
   6  * copy of this software and associated documentation files (the "Software"),
   7  * to deal in the Software without restriction, including without limitation
   8  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   9  * and/or sell copies of the Software, and to permit persons to whom the
  10  * Software is furnished to do so, subject to the following conditions:
  11  *
  12  * The above copyright notice and this permission notice shall be included in
  13  * all copies or substantial portions of the Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  18  * THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
  19  * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF
  20  * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  21  * SOFTWARE.
  22  */
  23
  24 #include <drm/drmP.h>
  25
  26 #include "nouveau_drm.h"
  27 #include "nouveau_reg.h"
  28 #include "hw.h"
  29
  30 /****************************************************************************\
  31 *                                                                            *
  32 * The video arbitration routines calculate some "magic" numbers.  Fixes      *
  33 * the snow seen when accessing the framebuffer without it.                   *
  34 * It just works (I hope).                                                    *
  35 *                                                                            *
  36 \****************************************************************************/
  37
  38 struct nv_fifo_info {
  39         int lwm;
  40         int burst;
  41 };
  42
  43 struct nv_sim_state {
  44         int pclk_khz;
  45         int mclk_khz;
  46         int nvclk_khz;
  47         int bpp;
  48         int mem_page_miss;
  49         int mem_latency;
  50         int memory_type;
  51         int memory_width;
  52         int two_heads;
  53 };
  54
  55 static void
  56 nv04_calc_arb(struct nv_fifo_info *fifo, struct nv_sim_state *arb)
  57 {
  58         int pagemiss, cas, width, bpp;
  59         int nvclks, mclks, pclks, crtpagemiss;
  60         int found, mclk_extra, mclk_loop, cbs, m1, p1;
  61         int mclk_freq, pclk_freq, nvclk_freq;
  62         int us_m, us_n, us_p, crtc_drain_rate;
  63         int cpm_us, us_crt, clwm;
  64
  65         pclk_freq = arb->pclk_khz;
  66         mclk_freq = arb->mclk_khz;
  67         nvclk_freq = arb->nvclk_khz;
  68         pagemiss = arb->mem_page_miss;
  69         cas = arb->mem_latency;
  70         width = arb->memory_width >> 6;
  71         bpp = arb->bpp;
  72         cbs = 128;
  73
  74         pclks = 2;
  75         nvclks = 10;
  76         mclks = 13 + cas;
  77         mclk_extra = 3;
  78         found = 0;
  79
  80         while (!found) {
  81                 found = 1;
  82
  83                 mclk_loop = mclks + mclk_extra;
  84                 us_m = mclk_loop * 1000 * 1000 / mclk_freq;
  85                 us_n = nvclks * 1000 * 1000 / nvclk_freq;
  86                 us_p = nvclks * 1000 * 1000 / pclk_freq;
  87
  88                 crtc_drain_rate = pclk_freq * bpp / 8;
  89                 crtpagemiss = 2;
  90                 crtpagemiss += 1;
  91                 cpm_us = crtpagemiss * pagemiss * 1000 * 1000 / mclk_freq;
  92                 us_crt = cpm_us + us_m + us_n + us_p;
  93                 clwm = us_crt * crtc_drain_rate / (1000 * 1000);
  94                 clwm++;
  95
  96                 m1 = clwm + cbs - 512;
  97                 p1 = m1 * pclk_freq / mclk_freq;
  98                 p1 = p1 * bpp / 8;
  99                 if ((p1 < m1 && m1 > 0) || clwm > 519) {
 100                         found = !mclk_extra;
 101                         mclk_extra--;
 102                 }
 103                 if (clwm < 384)
 104                         clwm = 384;
 105
 106                 fifo->lwm = clwm;
 107                 fifo->burst = cbs;
 108         }
 109 }
 110
 111 static void
 112 nv10_calc_arb(struct nv_fifo_info *fifo, struct nv_sim_state *arb)
 113 {
 114         int fill_rate, drain_rate;
 115         int pclks, nvclks, mclks, xclks;
 116         int pclk_freq, nvclk_freq, mclk_freq;
 117         int fill_lat, extra_lat;
 118         int max_burst_o, max_burst_l;
 119         int fifo_len, min_lwm, max_lwm;
 120         const int burst_lat = 80; /* Maximum allowable latency due
 121                                    * to the CRTC FIFO burst. (ns) */
 122
 123         pclk_freq = arb->pclk_khz;
 124         nvclk_freq = arb->nvclk_khz;
 125         mclk_freq = arb->mclk_khz;
 126
 127         fill_rate = mclk_freq * arb->memory_width / 8; /* kB/s */
 128         drain_rate = pclk_freq * arb->bpp / 8; /* kB/s */
 129
 130         fifo_len = arb->two_heads ? 1536 : 1024; /* B */
 131
 132         /* Fixed FIFO refill latency. */
 133
 134         pclks = 4;      /* lwm detect. */
 135
 136         nvclks = 3      /* lwm -> sync. */
 137                 + 2     /* fbi bus cycles (1 req + 1 busy) */
 138                 + 1     /* 2 edge sync.  may be very close to edge so
 139                          * just put one. */
 140                 + 1     /* fbi_d_rdv_n */
 141                 + 1     /* Fbi_d_rdata */
 142                 + 1;    /* crtfifo load */
 143
 144         mclks = 1       /* 2 edge sync.  may be very close to edge so
 145                          * just put one. */
 146                 + 1     /* arb_hp_req */
 147                 + 5     /* tiling pipeline */
 148                 + 2     /* latency fifo */
 149                 + 2     /* memory request to fbio block */
 150                 + 7;    /* data returned from fbio block */
 151
 152         /* Need to accumulate 256 bits for read */
 153         mclks += (arb->memory_type == 0 ? 2 : 1)
 154                 * arb->memory_width / 32;
 155
 156         fill_lat = mclks * 1000 * 1000 / mclk_freq   /* minimum mclk latency */
 157                 + nvclks * 1000 * 1000 / nvclk_freq  /* nvclk latency */
 158                 + pclks * 1000 * 1000 / pclk_freq;   /* pclk latency */
 159
 160         /* Conditional FIFO refill latency. */
 161
 162         xclks = 2 * arb->mem_page_miss + mclks /* Extra latency due to
 163                                                 * the overlay. */
 164                 + 2 * arb->mem_page_miss       /* Extra pagemiss latency. */
 165                 + (arb->bpp == 32 ? 8 : 4);    /* Margin of error. */
 166
 167         extra_lat = xclks * 1000 * 1000 / mclk_freq;
 168
 169         if (arb->two_heads)
 170                 /* Account for another CRTC. */
 171                 extra_lat += fill_lat + extra_lat + burst_lat;
 172
 173         /* FIFO burst */
 174
 175         /* Max burst not leading to overflows. */
 176         max_burst_o = (1 + fifo_len - extra_lat * drain_rate / (1000 * 1000))
 177                 * (fill_rate / 1000) / ((fill_rate - drain_rate) / 1000);
 178         fifo->burst = min(max_burst_o, 1024);
 179
 180         /* Max burst value with an acceptable latency. */
 181         max_burst_l = burst_lat * fill_rate / (1000 * 1000);
 182         fifo->burst = min(max_burst_l, fifo->burst);
 183
 184         fifo->burst = rounddown_pow_of_two(fifo->burst);
 185
 186         /* FIFO low watermark */
 187
 188         min_lwm = (fill_lat + extra_lat) * drain_rate / (1000 * 1000) + 1;
 189         max_lwm = fifo_len - fifo->burst
 190                 + fill_lat * drain_rate / (1000 * 1000)
 191                 + fifo->burst * drain_rate / fill_rate;
 192
 193         fifo->lwm = min_lwm + 10 * (max_lwm - min_lwm) / 100; /* Empirical. */
 194 }
 195
 196 static void
 197 nv04_update_arb(struct drm_device *dev, int VClk, int bpp,
 198                 int *burst, int *lwm)
 199 {
 200         struct nouveau_drm *drm = nouveau_drm(dev);
 201         struct nouveau_device *device = nouveau_dev(dev);
 202         struct nv_fifo_info fifo_data;
 203         struct nv_sim_state sim_data;
 204         int MClk = nouveau_hw_get_clock(dev, PLL_MEMORY);
 205         int NVClk = nouveau_hw_get_clock(dev, PLL_CORE);
 206         uint32_t cfg1 = nv_rd32(device, NV04_PFB_CFG1);
 207
 208         sim_data.pclk_khz = VClk;
 209         sim_data.mclk_khz = MClk;
 210         sim_data.nvclk_khz = NVClk;
 211         sim_data.bpp = bpp;
 212         sim_data.two_heads = nv_two_heads(dev);
 213         if ((dev->pdev->device & 0xffff) == 0x01a0 /*CHIPSET_NFORCE*/ ||
 214             (dev->pdev->device & 0xffff) == 0x01f0 /*CHIPSET_NFORCE2*/) {
 215                 uint32_t type;
 216
 217                 pci_read_config_dword(pci_get_bus_and_slot(0, 1), 0x7c, &type);
 218
 219                 sim_data.memory_type = (type >> 12) & 1;
 220                 sim_data.memory_width = 64;
 221                 sim_data.mem_latency = 3;
 222                 sim_data.mem_page_miss = 10;
 223         } else {
 224                 sim_data.memory_type = nv_rd32(device, NV04_PFB_CFG0) & 0x1;
 225                 sim_data.memory_width = (nv_rd32(device, NV_PEXTDEV_BOOT_0) & 0x10) ? 128 : 64;
 226                 sim_data.mem_latency = cfg1 & 0xf;
 227                 sim_data.mem_page_miss = ((cfg1 >> 4) & 0xf) + ((cfg1 >> 31) & 0x1);
 228         }
 229
 230         if (nv_device(drm->device)->card_type == NV_04)
 231                 nv04_calc_arb(&fifo_data, &sim_data);
 232         else
 233                 nv10_calc_arb(&fifo_data, &sim_data);
 234
 235         *burst = ilog2(fifo_data.burst >> 4);
 236         *lwm = fifo_data.lwm >> 3;
 237 }
 238
 239 static void
 240 nv20_update_arb(int *burst, int *lwm)
 241 {
 242         unsigned int fifo_size, burst_size, graphics_lwm;
 243
 244         fifo_size = 2048;
 245         burst_size = 512;
 246         graphics_lwm = fifo_size - burst_size;
 247
 248         *burst = ilog2(burst_size >> 5);
 249         *lwm = graphics_lwm >> 3;
 250 }
 251
 252 void
 253 nouveau_calc_arb(struct drm_device *dev, int vclk, int bpp, int *burst, int *lwm)
 254 {
 255         struct nouveau_drm *drm = nouveau_drm(dev);
 256
 257         if (nv_device(drm->device)->card_type < NV_20)
 258                 nv04_update_arb(dev, vclk, bpp, burst, lwm);
 259         else if ((dev->pdev->device & 0xfff0) == 0x0240 /*CHIPSET_C51*/ ||
 260                  (dev->pdev->device & 0xfff0) == 0x03d0 /*CHIPSET_C512*/) {
 261                 *burst = 128;
 262                 *lwm = 0x0480;
 263         } else
 264                 nv20_update_arb(burst, lwm);
 265 }