diff options
Diffstat (limited to 'drivers/gpu/drm/sprd/megacores_pll.c')
-rw-r--r-- | drivers/gpu/drm/sprd/megacores_pll.c | 305 |
1 files changed, 305 insertions, 0 deletions
diff --git a/drivers/gpu/drm/sprd/megacores_pll.c b/drivers/gpu/drm/sprd/megacores_pll.c new file mode 100644 index 000000000..3091dfdc1 --- /dev/null +++ b/drivers/gpu/drm/sprd/megacores_pll.c @@ -0,0 +1,305 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2020 Unisoc Inc. + */ + +#include <asm/div64.h> +#include <linux/delay.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/regmap.h> +#include <linux/string.h> + +#include "sprd_dsi.h" + +#define L 0 +#define H 1 +#define CLK 0 +#define DATA 1 +#define INFINITY 0xffffffff +#define MIN_OUTPUT_FREQ (100) + +#define AVERAGE(a, b) (min(a, b) + abs((b) - (a)) / 2) + +/* sharkle */ +#define VCO_BAND_LOW 750 +#define VCO_BAND_MID 1100 +#define VCO_BAND_HIGH 1500 +#define PHY_REF_CLK 26000 + +static int dphy_calc_pll_param(struct dphy_pll *pll) +{ + const u32 khz = 1000; + const u32 mhz = 1000000; + const unsigned long long factor = 100; + unsigned long long tmp; + int i; + + pll->potential_fvco = pll->freq / khz; + pll->ref_clk = PHY_REF_CLK / khz; + + for (i = 0; i < 4; ++i) { + if (pll->potential_fvco >= VCO_BAND_LOW && + pll->potential_fvco <= VCO_BAND_HIGH) { + pll->fvco = pll->potential_fvco; + pll->out_sel = BIT(i); + break; + } + pll->potential_fvco <<= 1; + } + if (pll->fvco == 0) + return -EINVAL; + + if (pll->fvco >= VCO_BAND_LOW && pll->fvco <= VCO_BAND_MID) { + /* vco band control */ + pll->vco_band = 0x0; + /* low pass filter control */ + pll->lpf_sel = 1; + } else if (pll->fvco > VCO_BAND_MID && pll->fvco <= VCO_BAND_HIGH) { + pll->vco_band = 0x1; + pll->lpf_sel = 0; + } else { + return -EINVAL; + } + + pll->nint = pll->fvco / pll->ref_clk; + tmp = pll->fvco * factor * mhz; + do_div(tmp, pll->ref_clk); + tmp = tmp - pll->nint * factor * mhz; + tmp *= BIT(20); + do_div(tmp, 100000000); + pll->kint = (u32)tmp; + pll->refin = 3; /* pre-divider bypass */ + pll->sdm_en = true; /* use fraction N PLL */ + pll->fdk_s = 0x1; /* fraction */ + pll->cp_s = 0x0; + pll->det_delay = 0x1; + + return 0; +} + +static void dphy_set_pll_reg(struct dphy_pll *pll, struct regmap *regmap) +{ + u8 reg_val[9] = {0}; + int i; + + u8 reg_addr[] = { + 0x03, 0x04, 0x06, 0x08, 0x09, + 0x0a, 0x0b, 0x0e, 0x0f + }; + + reg_val[0] = 1 | (1 << 1) | (pll->lpf_sel << 2); + reg_val[1] = pll->div | (1 << 3) | (pll->cp_s << 5) | (pll->fdk_s << 7); + reg_val[2] = pll->nint; + reg_val[3] = pll->vco_band | (pll->sdm_en << 1) | (pll->refin << 2); + reg_val[4] = pll->kint >> 12; + reg_val[5] = pll->kint >> 4; + reg_val[6] = pll->out_sel | ((pll->kint << 4) & 0xf); + reg_val[7] = 1 << 4; + reg_val[8] = pll->det_delay; + + for (i = 0; i < sizeof(reg_addr); ++i) { + regmap_write(regmap, reg_addr[i], reg_val[i]); + DRM_DEBUG("%02x: %02x\n", reg_addr[i], reg_val[i]); + } +} + +int dphy_pll_config(struct dsi_context *ctx) +{ + struct sprd_dsi *dsi = container_of(ctx, struct sprd_dsi, ctx); + struct regmap *regmap = ctx->regmap; + struct dphy_pll *pll = &ctx->pll; + int ret; + + pll->freq = dsi->slave->hs_rate; + + /* FREQ = 26M * (NINT + KINT / 2^20) / out_sel */ + ret = dphy_calc_pll_param(pll); + if (ret) { + drm_err(dsi->drm, "failed to calculate dphy pll parameters\n"); + return ret; + } + dphy_set_pll_reg(pll, regmap); + + return 0; +} + +static void dphy_set_timing_reg(struct regmap *regmap, int type, u8 val[]) +{ + switch (type) { + case REQUEST_TIME: + regmap_write(regmap, 0x31, val[CLK]); + regmap_write(regmap, 0x41, val[DATA]); + regmap_write(regmap, 0x51, val[DATA]); + regmap_write(regmap, 0x61, val[DATA]); + regmap_write(regmap, 0x71, val[DATA]); + + regmap_write(regmap, 0x90, val[CLK]); + regmap_write(regmap, 0xa0, val[DATA]); + regmap_write(regmap, 0xb0, val[DATA]); + regmap_write(regmap, 0xc0, val[DATA]); + regmap_write(regmap, 0xd0, val[DATA]); + break; + case PREPARE_TIME: + regmap_write(regmap, 0x32, val[CLK]); + regmap_write(regmap, 0x42, val[DATA]); + regmap_write(regmap, 0x52, val[DATA]); + regmap_write(regmap, 0x62, val[DATA]); + regmap_write(regmap, 0x72, val[DATA]); + + regmap_write(regmap, 0x91, val[CLK]); + regmap_write(regmap, 0xa1, val[DATA]); + regmap_write(regmap, 0xb1, val[DATA]); + regmap_write(regmap, 0xc1, val[DATA]); + regmap_write(regmap, 0xd1, val[DATA]); + break; + case ZERO_TIME: + regmap_write(regmap, 0x33, val[CLK]); + regmap_write(regmap, 0x43, val[DATA]); + regmap_write(regmap, 0x53, val[DATA]); + regmap_write(regmap, 0x63, val[DATA]); + regmap_write(regmap, 0x73, val[DATA]); + + regmap_write(regmap, 0x92, val[CLK]); + regmap_write(regmap, 0xa2, val[DATA]); + regmap_write(regmap, 0xb2, val[DATA]); + regmap_write(regmap, 0xc2, val[DATA]); + regmap_write(regmap, 0xd2, val[DATA]); + break; + case TRAIL_TIME: + regmap_write(regmap, 0x34, val[CLK]); + regmap_write(regmap, 0x44, val[DATA]); + regmap_write(regmap, 0x54, val[DATA]); + regmap_write(regmap, 0x64, val[DATA]); + regmap_write(regmap, 0x74, val[DATA]); + + regmap_write(regmap, 0x93, val[CLK]); + regmap_write(regmap, 0xa3, val[DATA]); + regmap_write(regmap, 0xb3, val[DATA]); + regmap_write(regmap, 0xc3, val[DATA]); + regmap_write(regmap, 0xd3, val[DATA]); + break; + case EXIT_TIME: + regmap_write(regmap, 0x36, val[CLK]); + regmap_write(regmap, 0x46, val[DATA]); + regmap_write(regmap, 0x56, val[DATA]); + regmap_write(regmap, 0x66, val[DATA]); + regmap_write(regmap, 0x76, val[DATA]); + + regmap_write(regmap, 0x95, val[CLK]); + regmap_write(regmap, 0xA5, val[DATA]); + regmap_write(regmap, 0xB5, val[DATA]); + regmap_write(regmap, 0xc5, val[DATA]); + regmap_write(regmap, 0xd5, val[DATA]); + break; + case CLKPOST_TIME: + regmap_write(regmap, 0x35, val[CLK]); + regmap_write(regmap, 0x94, val[CLK]); + break; + + /* the following just use default value */ + case SETTLE_TIME: + fallthrough; + case TA_GET: + fallthrough; + case TA_GO: + fallthrough; + case TA_SURE: + fallthrough; + default: + break; + } +} + +void dphy_timing_config(struct dsi_context *ctx) +{ + struct regmap *regmap = ctx->regmap; + struct dphy_pll *pll = &ctx->pll; + const u32 factor = 2; + const u32 scale = 100; + u32 t_ui, t_byteck, t_half_byteck; + u32 range[2], constant; + u8 val[2]; + u32 tmp = 0; + + /* t_ui: 1 ui, byteck: 8 ui, half byteck: 4 ui */ + t_ui = 1000 * scale / (pll->freq / 1000); + t_byteck = t_ui << 3; + t_half_byteck = t_ui << 2; + constant = t_ui << 1; + + /* REQUEST_TIME: HS T-LPX: LP-01 + * For T-LPX, mipi spec defined min value is 50ns, + * but maybe it shouldn't be too small, because BTA, + * LP-10, LP-00, LP-01, all of this is related to T-LPX. + */ + range[L] = 50 * scale; + range[H] = INFINITY; + val[CLK] = DIV_ROUND_UP(range[L] * (factor << 1), t_byteck) - 2; + val[DATA] = val[CLK]; + dphy_set_timing_reg(regmap, REQUEST_TIME, val); + + /* PREPARE_TIME: HS sequence: LP-00 */ + range[L] = 38 * scale; + range[H] = 95 * scale; + tmp = AVERAGE(range[L], range[H]); + val[CLK] = DIV_ROUND_UP(AVERAGE(range[L], range[H]), t_half_byteck) - 1; + range[L] = 40 * scale + 4 * t_ui; + range[H] = 85 * scale + 6 * t_ui; + tmp |= AVERAGE(range[L], range[H]) << 16; + val[DATA] = DIV_ROUND_UP(AVERAGE(range[L], range[H]), t_half_byteck) - 1; + dphy_set_timing_reg(regmap, PREPARE_TIME, val); + + /* ZERO_TIME: HS-ZERO */ + range[L] = 300 * scale; + range[H] = INFINITY; + val[CLK] = DIV_ROUND_UP(range[L] * factor + (tmp & 0xffff) + - 525 * t_byteck / 100, t_byteck) - 2; + range[L] = 145 * scale + 10 * t_ui; + val[DATA] = DIV_ROUND_UP(range[L] * factor + + ((tmp >> 16) & 0xffff) - 525 * t_byteck / 100, + t_byteck) - 2; + dphy_set_timing_reg(regmap, ZERO_TIME, val); + + /* TRAIL_TIME: HS-TRAIL */ + range[L] = 60 * scale; + range[H] = INFINITY; + val[CLK] = DIV_ROUND_UP(range[L] * factor - constant, t_half_byteck); + range[L] = max(8 * t_ui, 60 * scale + 4 * t_ui); + val[DATA] = DIV_ROUND_UP(range[L] * 3 / 2 - constant, t_half_byteck) - 2; + dphy_set_timing_reg(regmap, TRAIL_TIME, val); + + /* EXIT_TIME: */ + range[L] = 100 * scale; + range[H] = INFINITY; + val[CLK] = DIV_ROUND_UP(range[L] * factor, t_byteck) - 2; + val[DATA] = val[CLK]; + dphy_set_timing_reg(regmap, EXIT_TIME, val); + + /* CLKPOST_TIME: */ + range[L] = 60 * scale + 52 * t_ui; + range[H] = INFINITY; + val[CLK] = DIV_ROUND_UP(range[L] * factor, t_byteck) - 2; + val[DATA] = val[CLK]; + dphy_set_timing_reg(regmap, CLKPOST_TIME, val); + + /* SETTLE_TIME: + * This time is used for receiver. So for transmitter, + * it can be ignored. + */ + + /* TA_GO: + * transmitter drives bridge state(LP-00) before releasing control, + * reg 0x1f default value: 0x04, which is good. + */ + + /* TA_SURE: + * After LP-10 state and before bridge state(LP-00), + * reg 0x20 default value: 0x01, which is good. + */ + + /* TA_GET: + * receiver drives Bridge state(LP-00) before releasing control + * reg 0x21 default value: 0x03, which is good. + */ +} |