diff options
Diffstat (limited to 'drivers/gpu/drm/i915/intel_dsi_pll.c')
| -rw-r--r-- | drivers/gpu/drm/i915/intel_dsi_pll.c | 300 |
1 files changed, 300 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/intel_dsi_pll.c b/drivers/gpu/drm/i915/intel_dsi_pll.c new file mode 100644 index 00000000000..ba79ec19da3 --- /dev/null +++ b/drivers/gpu/drm/i915/intel_dsi_pll.c @@ -0,0 +1,300 @@ +/* + * Copyright © 2013 Intel Corporation + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice (including the next + * paragraph) shall be included in all copies or substantial portions of the + * Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER + * DEALINGS IN THE SOFTWARE. + * + * Authors: + * Shobhit Kumar <shobhit.kumar@intel.com> + * Yogesh Mohan Marimuthu <yogesh.mohan.marimuthu@intel.com> + */ + +#include <linux/kernel.h> +#include "intel_drv.h" +#include "i915_drv.h" +#include "intel_dsi.h" + +#define DSI_HSS_PACKET_SIZE 4 +#define DSI_HSE_PACKET_SIZE 4 +#define DSI_HSA_PACKET_EXTRA_SIZE 6 +#define DSI_HBP_PACKET_EXTRA_SIZE 6 +#define DSI_HACTIVE_PACKET_EXTRA_SIZE 6 +#define DSI_HFP_PACKET_EXTRA_SIZE 6 +#define DSI_EOTP_PACKET_SIZE 4 + +struct dsi_mnp { + u32 dsi_pll_ctrl; + u32 dsi_pll_div; +}; + +static const u32 lfsr_converts[] = { + 426, 469, 234, 373, 442, 221, 110, 311, 411, /* 62 - 70 */ + 461, 486, 243, 377, 188, 350, 175, 343, 427, 213, /* 71 - 80 */ + 106, 53, 282, 397, 354, 227, 113, 56, 284, 142, /* 81 - 90 */ + 71, 35 /* 91 - 92 */ +}; + +#ifdef DSI_CLK_FROM_RR + +static u32 dsi_rr_formula(const struct drm_display_mode *mode, + int pixel_format, int video_mode_format, + int lane_count, bool eotp) +{ + u32 bpp; + u32 hactive, vactive, hfp, hsync, hbp, vfp, vsync, vbp; + u32 hsync_bytes, hbp_bytes, hactive_bytes, hfp_bytes; + u32 bytes_per_line, bytes_per_frame; + u32 num_frames; + u32 bytes_per_x_frames, bytes_per_x_frames_x_lanes; + u32 dsi_bit_clock_hz; + u32 dsi_clk; + + switch (pixel_format) { + default: + case VID_MODE_FORMAT_RGB888: + case VID_MODE_FORMAT_RGB666_LOOSE: + bpp = 24; + break; + case VID_MODE_FORMAT_RGB666: + bpp = 18; + break; + case VID_MODE_FORMAT_RGB565: + bpp = 16; + break; + } + + hactive = mode->hdisplay; + vactive = mode->vdisplay; + hfp = mode->hsync_start - mode->hdisplay; + hsync = mode->hsync_end - mode->hsync_start; + hbp = mode->htotal - mode->hsync_end; + + vfp = mode->vsync_start - mode->vdisplay; + vsync = mode->vsync_end - mode->vsync_start; + vbp = mode->vtotal - mode->vsync_end; + + hsync_bytes = DIV_ROUND_UP(hsync * bpp, 8); + hbp_bytes = DIV_ROUND_UP(hbp * bpp, 8); + hactive_bytes = DIV_ROUND_UP(hactive * bpp, 8); + hfp_bytes = DIV_ROUND_UP(hfp * bpp, 8); + + bytes_per_line = DSI_HSS_PACKET_SIZE + hsync_bytes + + DSI_HSA_PACKET_EXTRA_SIZE + DSI_HSE_PACKET_SIZE + + hbp_bytes + DSI_HBP_PACKET_EXTRA_SIZE + + hactive_bytes + DSI_HACTIVE_PACKET_EXTRA_SIZE + + hfp_bytes + DSI_HFP_PACKET_EXTRA_SIZE; + + /* + * XXX: Need to accurately calculate LP to HS transition timeout and add + * it to bytes_per_line/bytes_per_frame. + */ + + if (eotp && video_mode_format == VIDEO_MODE_BURST) + bytes_per_line += DSI_EOTP_PACKET_SIZE; + + bytes_per_frame = vsync * bytes_per_line + vbp * bytes_per_line + + vactive * bytes_per_line + vfp * bytes_per_line; + + if (eotp && + (video_mode_format == VIDEO_MODE_NON_BURST_WITH_SYNC_PULSE || + video_mode_format == VIDEO_MODE_NON_BURST_WITH_SYNC_EVENTS)) + bytes_per_frame += DSI_EOTP_PACKET_SIZE; + + num_frames = drm_mode_vrefresh(mode); + bytes_per_x_frames = num_frames * bytes_per_frame; + + bytes_per_x_frames_x_lanes = bytes_per_x_frames / lane_count; + + /* the dsi clock is divided by 2 in the hardware to get dsi ddr clock */ + dsi_bit_clock_hz = bytes_per_x_frames_x_lanes * 8; + dsi_clk = dsi_bit_clock_hz / 1000; + + if (eotp && video_mode_format == VIDEO_MODE_BURST) + dsi_clk *= 2; + + return dsi_clk; +} + +#else + +/* Get DSI clock from pixel clock */ +static u32 dsi_clk_from_pclk(const struct drm_display_mode *mode, + int pixel_format, int lane_count) +{ + u32 dsi_clk_khz; + u32 bpp; + + switch (pixel_format) { + default: + case VID_MODE_FORMAT_RGB888: + case VID_MODE_FORMAT_RGB666_LOOSE: + bpp = 24; + break; + case VID_MODE_FORMAT_RGB666: + bpp = 18; + break; + case VID_MODE_FORMAT_RGB565: + bpp = 16; + break; + } + + /* DSI data rate = pixel clock * bits per pixel / lane count + pixel clock is converted from KHz to Hz */ + dsi_clk_khz = DIV_ROUND_CLOSEST(mode->clock * bpp, lane_count); + + return dsi_clk_khz; +} + +#endif + +static int dsi_calc_mnp(u32 dsi_clk, struct dsi_mnp *dsi_mnp) +{ + u32 m, n, p; + u32 ref_clk; + u32 error; + u32 tmp_error; + int target_dsi_clk; + int calc_dsi_clk; + u32 calc_m; + u32 calc_p; + u32 m_seed; + + /* dsi_clk is expected in KHZ */ + if (dsi_clk < 300000 || dsi_clk > 1150000) { + DRM_ERROR("DSI CLK Out of Range\n"); + return -ECHRNG; + } + + ref_clk = 25000; + target_dsi_clk = dsi_clk; + error = 0xFFFFFFFF; + tmp_error = 0xFFFFFFFF; + calc_m = 0; + calc_p = 0; + + for (m = 62; m <= 92; m++) { + for (p = 2; p <= 6; p++) { + /* Find the optimal m and p divisors + with minimal error +/- the required clock */ + calc_dsi_clk = (m * ref_clk) / p; + if (calc_dsi_clk == target_dsi_clk) { + calc_m = m; + calc_p = p; + error = 0; + break; + } else + tmp_error = abs(target_dsi_clk - calc_dsi_clk); + + if (tmp_error < error) { + error = tmp_error; + calc_m = m; + calc_p = p; + } + } + + if (error == 0) + break; + } + + m_seed = lfsr_converts[calc_m - 62]; + n = 1; + dsi_mnp->dsi_pll_ctrl = 1 << (DSI_PLL_P1_POST_DIV_SHIFT + calc_p - 2); + dsi_mnp->dsi_pll_div = (n - 1) << DSI_PLL_N1_DIV_SHIFT | + m_seed << DSI_PLL_M1_DIV_SHIFT; + + return 0; +} + +/* + * XXX: The muxing and gating is hard coded for now. Need to add support for + * sharing PLLs with two DSI outputs. + */ +static void vlv_configure_dsi_pll(struct intel_encoder *encoder) +{ + struct drm_i915_private *dev_priv = encoder->base.dev->dev_private; + struct intel_crtc *intel_crtc = to_intel_crtc(encoder->base.crtc); + const struct drm_display_mode *mode = &intel_crtc->config.adjusted_mode; + struct intel_dsi *intel_dsi = enc_to_intel_dsi(&encoder->base); + int ret; + struct dsi_mnp dsi_mnp; + u32 dsi_clk; + + dsi_clk = dsi_clk_from_pclk(mode, intel_dsi->pixel_format, + intel_dsi->lane_count); + + ret = dsi_calc_mnp(dsi_clk, &dsi_mnp); + if (ret) { + DRM_DEBUG_KMS("dsi_calc_mnp failed\n"); + return; + } + + dsi_mnp.dsi_pll_ctrl |= DSI_PLL_CLK_GATE_DSI0_DSIPLL; + + DRM_DEBUG_KMS("dsi pll div %08x, ctrl %08x\n", + dsi_mnp.dsi_pll_div, dsi_mnp.dsi_pll_ctrl); + + vlv_cck_write(dev_priv, CCK_REG_DSI_PLL_CONTROL, 0); + vlv_cck_write(dev_priv, CCK_REG_DSI_PLL_DIVIDER, dsi_mnp.dsi_pll_div); + vlv_cck_write(dev_priv, CCK_REG_DSI_PLL_CONTROL, dsi_mnp.dsi_pll_ctrl); +} + +void vlv_enable_dsi_pll(struct intel_encoder *encoder) +{ + struct drm_i915_private *dev_priv = encoder->base.dev->dev_private; + u32 tmp; + + DRM_DEBUG_KMS("\n"); + + mutex_lock(&dev_priv->dpio_lock); + + vlv_configure_dsi_pll(encoder); + + /* wait at least 0.5 us after ungating before enabling VCO */ + usleep_range(1, 10); + + tmp = vlv_cck_read(dev_priv, CCK_REG_DSI_PLL_CONTROL); + tmp |= DSI_PLL_VCO_EN; + vlv_cck_write(dev_priv, CCK_REG_DSI_PLL_CONTROL, tmp); + + mutex_unlock(&dev_priv->dpio_lock); + + if (wait_for(I915_READ(PIPECONF(PIPE_A)) & PIPECONF_DSI_PLL_LOCKED, 20)) { + DRM_ERROR("DSI PLL lock failed\n"); + return; + } + + DRM_DEBUG_KMS("DSI PLL locked\n"); +} + +void vlv_disable_dsi_pll(struct intel_encoder *encoder) +{ + struct drm_i915_private *dev_priv = encoder->base.dev->dev_private; + u32 tmp; + + DRM_DEBUG_KMS("\n"); + + mutex_lock(&dev_priv->dpio_lock); + + tmp = vlv_cck_read(dev_priv, CCK_REG_DSI_PLL_CONTROL); + tmp &= ~DSI_PLL_VCO_EN; + tmp |= DSI_PLL_LDO_GATE; + vlv_cck_write(dev_priv, CCK_REG_DSI_PLL_CONTROL, tmp); + + mutex_unlock(&dev_priv->dpio_lock); +} |