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 "nouveau_drv.h"
25#include "nouveau_reg.h"
26#include "hw.h"
27
28/****************************************************************************\
29* *
30* The video arbitration routines calculate some "magic" numbers. Fixes *
31* the snow seen when accessing the framebuffer without it. *
32* It just works (I hope). *
33* *
34\****************************************************************************/
35
36struct nv_fifo_info {
37 int lwm;
38 int burst;
39};
40
41struct nv_sim_state {
42 int pclk_khz;
43 int mclk_khz;
44 int nvclk_khz;
45 int bpp;
46 int mem_page_miss;
47 int mem_latency;
48 int memory_type;
49 int memory_width;
50 int two_heads;
51};
52
53static void
54nv04_calc_arb(struct nv_fifo_info *fifo, struct nv_sim_state *arb)
55{
56 int pagemiss, cas, bpp;
57 int nvclks, mclks, crtpagemiss;
58 int found, mclk_extra, mclk_loop, cbs, m1, p1;
59 int mclk_freq, pclk_freq, nvclk_freq;
60 int us_m, us_n, us_p, crtc_drain_rate;
61 int cpm_us, us_crt, clwm;
62
63 pclk_freq = arb->pclk_khz;
64 mclk_freq = arb->mclk_khz;
65 nvclk_freq = arb->nvclk_khz;
66 pagemiss = arb->mem_page_miss;
67 cas = arb->mem_latency;
68 bpp = arb->bpp;
69 cbs = 128;
70
71 nvclks = 10;
72 mclks = 13 + cas;
73 mclk_extra = 3;
74 found = 0;
75
76 while (!found) {
77 found = 1;
78
79 mclk_loop = mclks + mclk_extra;
80 us_m = mclk_loop * 1000 * 1000 / mclk_freq;
81 us_n = nvclks * 1000 * 1000 / nvclk_freq;
82 us_p = nvclks * 1000 * 1000 / pclk_freq;
83
84 crtc_drain_rate = pclk_freq * bpp / 8;
85 crtpagemiss = 2;
86 crtpagemiss += 1;
87 cpm_us = crtpagemiss * pagemiss * 1000 * 1000 / mclk_freq;
88 us_crt = cpm_us + us_m + us_n + us_p;
89 clwm = us_crt * crtc_drain_rate / (1000 * 1000);
90 clwm++;
91
92 m1 = clwm + cbs - 512;
93 p1 = m1 * pclk_freq / mclk_freq;
94 p1 = p1 * bpp / 8;
95 if ((p1 < m1 && m1 > 0) || clwm > 519) {
96 found = !mclk_extra;
97 mclk_extra--;
98 }
99 if (clwm < 384)
100 clwm = 384;
101
102 fifo->lwm = clwm;
103 fifo->burst = cbs;
104 }
105}
106
107static void
108nv10_calc_arb(struct nv_fifo_info *fifo, struct nv_sim_state *arb)
109{
110 int fill_rate, drain_rate;
111 int pclks, nvclks, mclks, xclks;
112 int pclk_freq, nvclk_freq, mclk_freq;
113 int fill_lat, extra_lat;
114 int max_burst_o, max_burst_l;
115 int fifo_len, min_lwm, max_lwm;
116 const int burst_lat = 80; /* Maximum allowable latency due
117 * to the CRTC FIFO burst. (ns) */
118
119 pclk_freq = arb->pclk_khz;
120 nvclk_freq = arb->nvclk_khz;
121 mclk_freq = arb->mclk_khz;
122
123 fill_rate = mclk_freq * arb->memory_width / 8; /* kB/s */
124 drain_rate = pclk_freq * arb->bpp / 8; /* kB/s */
125
126 fifo_len = arb->two_heads ? 1536 : 1024; /* B */
127
128 /* Fixed FIFO refill latency. */
129
130 pclks = 4; /* lwm detect. */
131
132 nvclks = 3 /* lwm -> sync. */
133 + 2 /* fbi bus cycles (1 req + 1 busy) */
134 + 1 /* 2 edge sync. may be very close to edge so
135 * just put one. */
136 + 1 /* fbi_d_rdv_n */
137 + 1 /* Fbi_d_rdata */
138 + 1; /* crtfifo load */
139
140 mclks = 1 /* 2 edge sync. may be very close to edge so
141 * just put one. */
142 + 1 /* arb_hp_req */
143 + 5 /* tiling pipeline */
144 + 2 /* latency fifo */
145 + 2 /* memory request to fbio block */
146 + 7; /* data returned from fbio block */
147
148 /* Need to accumulate 256 bits for read */
149 mclks += (arb->memory_type == 0 ? 2 : 1)
150 * arb->memory_width / 32;
151
152 fill_lat = mclks * 1000 * 1000 / mclk_freq /* minimum mclk latency */
153 + nvclks * 1000 * 1000 / nvclk_freq /* nvclk latency */
154 + pclks * 1000 * 1000 / pclk_freq; /* pclk latency */
155
156 /* Conditional FIFO refill latency. */
157
158 xclks = 2 * arb->mem_page_miss + mclks /* Extra latency due to
159 * the overlay. */
160 + 2 * arb->mem_page_miss /* Extra pagemiss latency. */
161 + (arb->bpp == 32 ? 8 : 4); /* Margin of error. */
162
163 extra_lat = xclks * 1000 * 1000 / mclk_freq;
164
165 if (arb->two_heads)
166 /* Account for another CRTC. */
167 extra_lat += fill_lat + extra_lat + burst_lat;
168
169 /* FIFO burst */
170
171 /* Max burst not leading to overflows. */
172 max_burst_o = (1 + fifo_len - extra_lat * drain_rate / (1000 * 1000))
173 * (fill_rate / 1000) / ((fill_rate - drain_rate) / 1000);
174 fifo->burst = min(max_burst_o, 1024);
175
176 /* Max burst value with an acceptable latency. */
177 max_burst_l = burst_lat * fill_rate / (1000 * 1000);
178 fifo->burst = min(max_burst_l, fifo->burst);
179
180 fifo->burst = rounddown_pow_of_two(fifo->burst);
181
182 /* FIFO low watermark */
183
184 min_lwm = (fill_lat + extra_lat) * drain_rate / (1000 * 1000) + 1;
185 max_lwm = fifo_len - fifo->burst
186 + fill_lat * drain_rate / (1000 * 1000)
187 + fifo->burst * drain_rate / fill_rate;
188
189 fifo->lwm = min_lwm + 10 * (max_lwm - min_lwm) / 100; /* Empirical. */
190}
191
192static void
193nv04_update_arb(struct drm_device *dev, int VClk, int bpp,
194 int *burst, int *lwm)
195{
196 struct nouveau_drm *drm = nouveau_drm(dev);
197 struct nvif_object *device = &nouveau_drm(dev)->client.device.object;
198 struct nv_fifo_info fifo_data;
199 struct nv_sim_state sim_data;
200 int MClk = nouveau_hw_get_clock(dev, PLL_MEMORY);
201 int NVClk = nouveau_hw_get_clock(dev, PLL_CORE);
202 uint32_t cfg1 = nvif_rd32(device, NV04_PFB_CFG1);
203 struct pci_dev *pdev = to_pci_dev(dev->dev);
204
205 sim_data.pclk_khz = VClk;
206 sim_data.mclk_khz = MClk;
207 sim_data.nvclk_khz = NVClk;
208 sim_data.bpp = bpp;
209 sim_data.two_heads = nv_two_heads(dev);
210 if ((pdev->device & 0xffff) == 0x01a0 /*CHIPSET_NFORCE*/ ||
211 (pdev->device & 0xffff) == 0x01f0 /*CHIPSET_NFORCE2*/) {
212 uint32_t type;
213 int domain = pci_domain_nr(pdev->bus);
214
215 pci_read_config_dword(pci_get_domain_bus_and_slot(domain, 0, 1),
216 0x7c, &type);
217
218 sim_data.memory_type = (type >> 12) & 1;
219 sim_data.memory_width = 64;
220 sim_data.mem_latency = 3;
221 sim_data.mem_page_miss = 10;
222 } else {
223 sim_data.memory_type = nvif_rd32(device, NV04_PFB_CFG0) & 0x1;
224 sim_data.memory_width = (nvif_rd32(device, NV_PEXTDEV_BOOT_0) & 0x10) ? 128 : 64;
225 sim_data.mem_latency = cfg1 & 0xf;
226 sim_data.mem_page_miss = ((cfg1 >> 4) & 0xf) + ((cfg1 >> 31) & 0x1);
227 }
228
229 if (drm->client.device.info.family == NV_DEVICE_INFO_V0_TNT)
230 nv04_calc_arb(fifo: &fifo_data, arb: &sim_data);
231 else
232 nv10_calc_arb(fifo: &fifo_data, arb: &sim_data);
233
234 *burst = ilog2(fifo_data.burst >> 4);
235 *lwm = fifo_data.lwm >> 3;
236}
237
238static void
239nv20_update_arb(int *burst, int *lwm)
240{
241 unsigned int fifo_size, burst_size, graphics_lwm;
242
243 fifo_size = 2048;
244 burst_size = 512;
245 graphics_lwm = fifo_size - burst_size;
246
247 *burst = ilog2(burst_size >> 5);
248 *lwm = graphics_lwm >> 3;
249}
250
251void
252nouveau_calc_arb(struct drm_device *dev, int vclk, int bpp, int *burst, int *lwm)
253{
254 struct nouveau_drm *drm = nouveau_drm(dev);
255 struct pci_dev *pdev = to_pci_dev(dev->dev);
256
257 if (drm->client.device.info.family < NV_DEVICE_INFO_V0_KELVIN)
258 nv04_update_arb(dev, VClk: vclk, bpp, burst, lwm);
259 else if ((pdev->device & 0xfff0) == 0x0240 /*CHIPSET_C51*/ ||
260 (pdev->device & 0xfff0) == 0x03d0 /*CHIPSET_C512*/) {
261 *burst = 128;
262 *lwm = 0x0480;
263 } else
264 nv20_update_arb(burst, lwm);
265}
266

source code of linux/drivers/gpu/drm/nouveau/dispnv04/arb.c