1 /* 2 * Copyright © 2013 Intel Corporation 3 * 4 * Permission is hereby granted, free of charge, to any person obtaining a 5 * copy of this software and associated documentation files (the "Software"), 6 * to deal in the Software without restriction, including without limitation 7 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 8 * and/or sell copies of the Software, and to permit persons to whom the 9 * Software is furnished to do so, subject to the following conditions: 10 * 11 * The above copyright notice and this permission notice (including the next 12 * paragraph) shall be included in all copies or substantial portions of the 13 * 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 OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 21 * DEALINGS IN THE SOFTWARE. 22 * 23 * Authors: 24 * Shobhit Kumar <shobhit.kumar@intel.com> 25 * Yogesh Mohan Marimuthu <yogesh.mohan.marimuthu@intel.com> 26 */ 27 28 #include <linux/kernel.h> 29 #include "intel_drv.h" 30 #include "i915_drv.h" 31 #include "intel_dsi.h" 32 33 #define DSI_HSS_PACKET_SIZE 4 34 #define DSI_HSE_PACKET_SIZE 4 35 #define DSI_HSA_PACKET_EXTRA_SIZE 6 36 #define DSI_HBP_PACKET_EXTRA_SIZE 6 37 #define DSI_HACTIVE_PACKET_EXTRA_SIZE 6 38 #define DSI_HFP_PACKET_EXTRA_SIZE 6 39 #define DSI_EOTP_PACKET_SIZE 4 40 41 struct dsi_mnp { 42 u32 dsi_pll_ctrl; 43 u32 dsi_pll_div; 44 }; 45 46 static const u32 lfsr_converts[] = { 47 426, 469, 234, 373, 442, 221, 110, 311, 411, /* 62 - 70 */ 48 461, 486, 243, 377, 188, 350, 175, 343, 427, 213, /* 71 - 80 */ 49 106, 53, 282, 397, 354, 227, 113, 56, 284, 142, /* 81 - 90 */ 50 71, 35 /* 91 - 92 */ 51 }; 52 53 #ifdef DSI_CLK_FROM_RR 54 55 static u32 dsi_rr_formula(const struct drm_display_mode *mode, 56 int pixel_format, int video_mode_format, 57 int lane_count, bool eotp) 58 { 59 u32 bpp; 60 u32 hactive, vactive, hfp, hsync, hbp, vfp, vsync, vbp; 61 u32 hsync_bytes, hbp_bytes, hactive_bytes, hfp_bytes; 62 u32 bytes_per_line, bytes_per_frame; 63 u32 num_frames; 64 u32 bytes_per_x_frames, bytes_per_x_frames_x_lanes; 65 u32 dsi_bit_clock_hz; 66 u32 dsi_clk; 67 68 switch (pixel_format) { 69 default: 70 case VID_MODE_FORMAT_RGB888: 71 case VID_MODE_FORMAT_RGB666_LOOSE: 72 bpp = 24; 73 break; 74 case VID_MODE_FORMAT_RGB666: 75 bpp = 18; 76 break; 77 case VID_MODE_FORMAT_RGB565: 78 bpp = 16; 79 break; 80 } 81 82 hactive = mode->hdisplay; 83 vactive = mode->vdisplay; 84 hfp = mode->hsync_start - mode->hdisplay; 85 hsync = mode->hsync_end - mode->hsync_start; 86 hbp = mode->htotal - mode->hsync_end; 87 88 vfp = mode->vsync_start - mode->vdisplay; 89 vsync = mode->vsync_end - mode->vsync_start; 90 vbp = mode->vtotal - mode->vsync_end; 91 92 hsync_bytes = DIV_ROUND_UP(hsync * bpp, 8); 93 hbp_bytes = DIV_ROUND_UP(hbp * bpp, 8); 94 hactive_bytes = DIV_ROUND_UP(hactive * bpp, 8); 95 hfp_bytes = DIV_ROUND_UP(hfp * bpp, 8); 96 97 bytes_per_line = DSI_HSS_PACKET_SIZE + hsync_bytes + 98 DSI_HSA_PACKET_EXTRA_SIZE + DSI_HSE_PACKET_SIZE + 99 hbp_bytes + DSI_HBP_PACKET_EXTRA_SIZE + 100 hactive_bytes + DSI_HACTIVE_PACKET_EXTRA_SIZE + 101 hfp_bytes + DSI_HFP_PACKET_EXTRA_SIZE; 102 103 /* 104 * XXX: Need to accurately calculate LP to HS transition timeout and add 105 * it to bytes_per_line/bytes_per_frame. 106 */ 107 108 if (eotp && video_mode_format == VIDEO_MODE_BURST) 109 bytes_per_line += DSI_EOTP_PACKET_SIZE; 110 111 bytes_per_frame = vsync * bytes_per_line + vbp * bytes_per_line + 112 vactive * bytes_per_line + vfp * bytes_per_line; 113 114 if (eotp && 115 (video_mode_format == VIDEO_MODE_NON_BURST_WITH_SYNC_PULSE || 116 video_mode_format == VIDEO_MODE_NON_BURST_WITH_SYNC_EVENTS)) 117 bytes_per_frame += DSI_EOTP_PACKET_SIZE; 118 119 num_frames = drm_mode_vrefresh(mode); 120 bytes_per_x_frames = num_frames * bytes_per_frame; 121 122 bytes_per_x_frames_x_lanes = bytes_per_x_frames / lane_count; 123 124 /* the dsi clock is divided by 2 in the hardware to get dsi ddr clock */ 125 dsi_bit_clock_hz = bytes_per_x_frames_x_lanes * 8; 126 dsi_clk = dsi_bit_clock_hz / 1000; 127 128 if (eotp && video_mode_format == VIDEO_MODE_BURST) 129 dsi_clk *= 2; 130 131 return dsi_clk; 132 } 133 134 #else 135 136 /* Get DSI clock from pixel clock */ 137 static u32 dsi_clk_from_pclk(const struct drm_display_mode *mode, 138 int pixel_format, int lane_count) 139 { 140 u32 dsi_clk_khz; 141 u32 bpp; 142 143 switch (pixel_format) { 144 default: 145 case VID_MODE_FORMAT_RGB888: 146 case VID_MODE_FORMAT_RGB666_LOOSE: 147 bpp = 24; 148 break; 149 case VID_MODE_FORMAT_RGB666: 150 bpp = 18; 151 break; 152 case VID_MODE_FORMAT_RGB565: 153 bpp = 16; 154 break; 155 } 156 157 /* DSI data rate = pixel clock * bits per pixel / lane count 158 pixel clock is converted from KHz to Hz */ 159 dsi_clk_khz = DIV_ROUND_CLOSEST(mode->clock * bpp, lane_count); 160 161 return dsi_clk_khz; 162 } 163 164 #endif 165 166 static int dsi_calc_mnp(u32 dsi_clk, struct dsi_mnp *dsi_mnp) 167 { 168 u32 m, n, p; 169 u32 ref_clk; 170 u32 error; 171 u32 tmp_error; 172 int target_dsi_clk; 173 int calc_dsi_clk; 174 u32 calc_m; 175 u32 calc_p; 176 u32 m_seed; 177 178 /* dsi_clk is expected in KHZ */ 179 if (dsi_clk < 300000 || dsi_clk > 1150000) { 180 DRM_ERROR("DSI CLK Out of Range\n"); 181 return -ECHRNG; 182 } 183 184 ref_clk = 25000; 185 target_dsi_clk = dsi_clk; 186 error = 0xFFFFFFFF; 187 tmp_error = 0xFFFFFFFF; 188 calc_m = 0; 189 calc_p = 0; 190 191 for (m = 62; m <= 92; m++) { 192 for (p = 2; p <= 6; p++) { 193 /* Find the optimal m and p divisors 194 with minimal error +/- the required clock */ 195 calc_dsi_clk = (m * ref_clk) / p; 196 if (calc_dsi_clk == target_dsi_clk) { 197 calc_m = m; 198 calc_p = p; 199 error = 0; 200 break; 201 } else 202 tmp_error = abs(target_dsi_clk - calc_dsi_clk); 203 204 if (tmp_error < error) { 205 error = tmp_error; 206 calc_m = m; 207 calc_p = p; 208 } 209 } 210 211 if (error == 0) 212 break; 213 } 214 215 m_seed = lfsr_converts[calc_m - 62]; 216 n = 1; 217 dsi_mnp->dsi_pll_ctrl = 1 << (DSI_PLL_P1_POST_DIV_SHIFT + calc_p - 2); 218 dsi_mnp->dsi_pll_div = (n - 1) << DSI_PLL_N1_DIV_SHIFT | 219 m_seed << DSI_PLL_M1_DIV_SHIFT; 220 221 return 0; 222 } 223 224 /* 225 * XXX: The muxing and gating is hard coded for now. Need to add support for 226 * sharing PLLs with two DSI outputs. 227 */ 228 static void vlv_configure_dsi_pll(struct intel_encoder *encoder) 229 { 230 struct drm_i915_private *dev_priv = encoder->base.dev->dev_private; 231 struct intel_crtc *intel_crtc = to_intel_crtc(encoder->base.crtc); 232 const struct drm_display_mode *mode = &intel_crtc->config.adjusted_mode; 233 struct intel_dsi *intel_dsi = enc_to_intel_dsi(&encoder->base); 234 int ret; 235 struct dsi_mnp dsi_mnp; 236 u32 dsi_clk; 237 238 dsi_clk = dsi_clk_from_pclk(mode, intel_dsi->pixel_format, 239 intel_dsi->lane_count); 240 241 ret = dsi_calc_mnp(dsi_clk, &dsi_mnp); 242 if (ret) { 243 DRM_DEBUG_KMS("dsi_calc_mnp failed\n"); 244 return; 245 } 246 247 dsi_mnp.dsi_pll_ctrl |= DSI_PLL_CLK_GATE_DSI0_DSIPLL; 248 249 DRM_DEBUG_KMS("dsi pll div %08x, ctrl %08x\n", 250 dsi_mnp.dsi_pll_div, dsi_mnp.dsi_pll_ctrl); 251 252 vlv_cck_write(dev_priv, CCK_REG_DSI_PLL_CONTROL, 0); 253 vlv_cck_write(dev_priv, CCK_REG_DSI_PLL_DIVIDER, dsi_mnp.dsi_pll_div); 254 vlv_cck_write(dev_priv, CCK_REG_DSI_PLL_CONTROL, dsi_mnp.dsi_pll_ctrl); 255 } 256 257 void vlv_enable_dsi_pll(struct intel_encoder *encoder) 258 { 259 struct drm_i915_private *dev_priv = encoder->base.dev->dev_private; 260 u32 tmp; 261 262 DRM_DEBUG_KMS("\n"); 263 264 mutex_lock(&dev_priv->dpio_lock); 265 266 vlv_configure_dsi_pll(encoder); 267 268 /* wait at least 0.5 us after ungating before enabling VCO */ 269 usleep_range(1, 10); 270 271 tmp = vlv_cck_read(dev_priv, CCK_REG_DSI_PLL_CONTROL); 272 tmp |= DSI_PLL_VCO_EN; 273 vlv_cck_write(dev_priv, CCK_REG_DSI_PLL_CONTROL, tmp); 274 275 mutex_unlock(&dev_priv->dpio_lock); 276 277 if (wait_for(I915_READ(PIPECONF(PIPE_A)) & PIPECONF_DSI_PLL_LOCKED, 20)) { 278 DRM_ERROR("DSI PLL lock failed\n"); 279 return; 280 } 281 282 DRM_DEBUG_KMS("DSI PLL locked\n"); 283 } 284 285 void vlv_disable_dsi_pll(struct intel_encoder *encoder) 286 { 287 struct drm_i915_private *dev_priv = encoder->base.dev->dev_private; 288 u32 tmp; 289 290 DRM_DEBUG_KMS("\n"); 291 292 mutex_lock(&dev_priv->dpio_lock); 293 294 tmp = vlv_cck_read(dev_priv, CCK_REG_DSI_PLL_CONTROL); 295 tmp &= ~DSI_PLL_VCO_EN; 296 tmp |= DSI_PLL_LDO_GATE; 297 vlv_cck_write(dev_priv, CCK_REG_DSI_PLL_CONTROL, tmp); 298 299 mutex_unlock(&dev_priv->dpio_lock); 300 } 301