From: Sakari Ailus <sakari.ai...@maxwell.research.nokia.com> Calculate PLL configuration based on input data: sensor configuration, board properties and sensor-specific limits.
Signed-off-by: Sakari Ailus <sakari.ai...@maxwell.research.nokia.com> --- drivers/media/video/Kconfig | 3 + drivers/media/video/Makefile | 2 + drivers/media/video/smiapp-pll.c | 419 ++++++++++++++++++++++++++++++++++++++ drivers/media/video/smiapp-pll.h | 103 ++++++++++ 4 files changed, 527 insertions(+), 0 deletions(-) create mode 100644 drivers/media/video/smiapp-pll.c create mode 100644 drivers/media/video/smiapp-pll.h diff --git a/drivers/media/video/Kconfig b/drivers/media/video/Kconfig index 9495b6a..7eac873 100644 --- a/drivers/media/video/Kconfig +++ b/drivers/media/video/Kconfig @@ -459,6 +459,9 @@ config VIDEO_AK881X comment "Camera sensor devices" +config VIDEO_SMIAPP_PLL + tristate + config VIDEO_OV7670 tristate "OmniVision OV7670 sensor support" depends on I2C && VIDEO_V4L2 diff --git a/drivers/media/video/Makefile b/drivers/media/video/Makefile index 563443c..2fed63d 100644 --- a/drivers/media/video/Makefile +++ b/drivers/media/video/Makefile @@ -76,6 +76,8 @@ obj-$(CONFIG_VIDEO_S5K6AA) += s5k6aa.o obj-$(CONFIG_VIDEO_ADP1653) += adp1653.o obj-$(CONFIG_VIDEO_AS3645A) += as3645a.o +obj-$(CONFIG_VIDEO_SMIAPP_PLL) += smiapp-pll.o + obj-$(CONFIG_SOC_CAMERA_IMX074) += imx074.o obj-$(CONFIG_SOC_CAMERA_MT9M001) += mt9m001.o obj-$(CONFIG_SOC_CAMERA_MT9M111) += mt9m111.o diff --git a/drivers/media/video/smiapp-pll.c b/drivers/media/video/smiapp-pll.c new file mode 100644 index 0000000..c8ffdc9 --- /dev/null +++ b/drivers/media/video/smiapp-pll.c @@ -0,0 +1,419 @@ +/* + * drivers/media/video/smiapp-pll.c + * + * Generic driver for SMIA/SMIA++ compliant camera modules + * + * Copyright (C) 2011--2012 Nokia Corporation + * Contact: Sakari Ailus <sakari.ai...@maxwell.research.nokia.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * version 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA + * 02110-1301 USA + * + */ + +#include <linux/gcd.h> +#include <linux/lcm.h> +#include <linux/module.h> + +#include "smiapp-pll.h" + +/* Return an even number or one. */ +static inline uint32_t clk_div_even(uint32_t a) +{ + return max_t(uint32_t, 1, a & ~1); +} + +/* Return an even number or one. */ +static inline uint32_t clk_div_even_up(uint32_t a) +{ + if (a == 1) + return 1; + return (a + 1) & ~1; +} + +static inline uint32_t is_one_or_even(uint32_t a) +{ + if (a == 1) + return 1; + if (a & 1) + return 0; + + return 1; +} + +static int bounds_check(struct device *dev, uint32_t val, + uint32_t min, uint32_t max, char *str) +{ + if (val >= min && val <= max) + return 0; + + dev_warn(dev, "%s out of bounds: %d (%d--%d)\n", str, val, min, max); + + return -EINVAL; +} + +static void print_pll(struct device *dev, struct smiapp_pll *pll) +{ + dev_dbg(dev, "pre_pll_clk_div\t%d\n", pll->pre_pll_clk_div); + dev_dbg(dev, "pll_multiplier \t%d\n", pll->pll_multiplier); + if (pll->flags != SMIAPP_PLL_FLAG_NO_OP_CLOCKS) { + dev_dbg(dev, "op_sys_clk_div \t%d\n", pll->op_sys_clk_div); + dev_dbg(dev, "op_pix_clk_div \t%d\n", pll->op_pix_clk_div); + } + dev_dbg(dev, "vt_sys_clk_div \t%d\n", pll->vt_sys_clk_div); + dev_dbg(dev, "vt_pix_clk_div \t%d\n", pll->vt_pix_clk_div); + + dev_dbg(dev, "ext_clk_freq_hz \t%d\n", pll->ext_clk_freq_hz); + dev_dbg(dev, "pll_ip_clk_freq_hz \t%d\n", pll->pll_ip_clk_freq_hz); + dev_dbg(dev, "pll_op_clk_freq_hz \t%d\n", pll->pll_op_clk_freq_hz); + if (pll->flags & SMIAPP_PLL_FLAG_NO_OP_CLOCKS) { + dev_dbg(dev, "op_sys_clk_freq_hz \t%d\n", + pll->op_sys_clk_freq_hz); + dev_dbg(dev, "op_pix_clk_freq_hz \t%d\n", + pll->op_pix_clk_freq_hz); + } + dev_dbg(dev, "vt_sys_clk_freq_hz \t%d\n", pll->vt_sys_clk_freq_hz); + dev_dbg(dev, "vt_pix_clk_freq_hz \t%d\n", pll->vt_pix_clk_freq_hz); +} + +int smiapp_pll_calculate(struct device *dev, struct smiapp_pll_limits *limits, + struct smiapp_pll *pll) +{ + uint32_t sys_div; + uint32_t best_pix_div = INT_MAX >> 1; + uint32_t vt_op_binning_div; + uint32_t lane_op_clock_ratio; + uint32_t mul, div; + uint32_t more_mul_min, more_mul_max; + uint32_t more_mul_factor; + uint32_t min_vt_div, max_vt_div, vt_div; + uint32_t min_sys_div, max_sys_div; + unsigned i; + int rval; + + if (pll->flags & SMIAPP_PLL_FLAG_OP_PIX_CLOCK_PER_LANE) + lane_op_clock_ratio = pll->lanes; + else + lane_op_clock_ratio = 1; + dev_dbg(dev, "lane_op_clock_ratio: %d\n", lane_op_clock_ratio); + + dev_dbg(dev, "binning: %dx%d\n", pll->binning_horizontal, + pll->binning_vertical); + + /* CSI transfers 2 bits per clock per lane; thus times 2 */ + pll->pll_op_clk_freq_hz = pll->link_freq * 2 + * (pll->lanes / lane_op_clock_ratio); + + /* Figure out limits for pre-pll divider based on extclk */ + dev_dbg(dev, "min / max pre_pll_clk_div: %d / %d\n", + limits->min_pre_pll_clk_div, limits->max_pre_pll_clk_div); + limits->max_pre_pll_clk_div = + min_t(uint16_t, limits->max_pre_pll_clk_div, + clk_div_even(pll->ext_clk_freq_hz / + limits->min_pll_ip_freq_hz)); + limits->min_pre_pll_clk_div = + max_t(uint16_t, limits->min_pre_pll_clk_div, + clk_div_even(pll->ext_clk_freq_hz / + limits->max_pll_ip_freq_hz)); + dev_dbg(dev, "pre-pll check: min / max pre_pll_clk_div: %d / %d\n", + limits->min_pre_pll_clk_div, limits->max_pre_pll_clk_div); + + i = gcd(pll->pll_op_clk_freq_hz, pll->ext_clk_freq_hz); + mul = div_u64(pll->pll_op_clk_freq_hz, i); + div = pll->ext_clk_freq_hz / i; + dev_dbg(dev, "mul %d / div %d\n", mul, div); + + limits->min_pre_pll_clk_div = + max_t(uint16_t, limits->min_pre_pll_clk_div, + clk_div_even_up( + DIV_ROUND_UP(mul * pll->ext_clk_freq_hz, + limits->max_pll_op_freq_hz))); + dev_dbg(dev, "pll_op check: min / max pre_pll_clk_div: %d / %d\n", + limits->min_pre_pll_clk_div, limits->max_pre_pll_clk_div); + + if (limits->min_pre_pll_clk_div > limits->max_pre_pll_clk_div) { + dev_err(dev, "unable to compute pre_pll divisor\n"); + return -EINVAL; + } + + pll->pre_pll_clk_div = limits->min_pre_pll_clk_div; + + /* + * Get pre_pll_clk_div so that our pll_op_clk_freq_hz won't be + * too high. + */ + dev_dbg(dev, "pre_pll_clk_div %d\n", pll->pre_pll_clk_div); + + /* Don't go above max pll multiplier. */ + more_mul_max = limits->max_pll_multiplier / mul; + dev_dbg(dev, "more_mul_max: max_pll_multiplier check: %d\n", + more_mul_max); + /* Don't go above max pll op frequency. */ + more_mul_max = + min_t(int, + more_mul_max, + limits->max_pll_op_freq_hz + / (pll->ext_clk_freq_hz / pll->pre_pll_clk_div * mul)); + dev_dbg(dev, "more_mul_max: max_pll_op_freq_hz check: %d\n", + more_mul_max); + /* Don't go above the division capability of op sys clock divider. */ + more_mul_max = min(more_mul_max, + limits->max_op_sys_clk_div * pll->pre_pll_clk_div + / div); + dev_dbg(dev, "more_mul_max: max_op_sys_clk_div check: %d\n", + more_mul_max); + /* Ensure we won't go above min_pll_multiplier. */ + more_mul_max = min(more_mul_max, + DIV_ROUND_UP(limits->max_pll_multiplier, mul)); + dev_dbg(dev, "more_mul_max: min_pll_multiplier check: %d\n", + more_mul_max); + + /* Ensure we won't go below min_pll_op_freq_hz. */ + more_mul_min = DIV_ROUND_UP(limits->min_pll_op_freq_hz, + pll->ext_clk_freq_hz / pll->pre_pll_clk_div + * mul); + dev_dbg(dev, "more_mul_min: min_pll_op_freq_hz check: %d\n", + more_mul_min); + /* Ensure we won't go below min_pll_multiplier. */ + more_mul_min = max(more_mul_min, + DIV_ROUND_UP(limits->min_pll_multiplier, mul)); + dev_dbg(dev, "more_mul_min: min_pll_multiplier check: %d\n", + more_mul_min); + + if (more_mul_min > more_mul_max) { + dev_warn(dev, + "unable to compute more_mul_min and more_mul_max"); + return -EINVAL; + } + + more_mul_factor = lcm(div, pll->pre_pll_clk_div) / div; + dev_dbg(dev, "more_mul_factor: %d\n", more_mul_factor); + more_mul_factor = lcm(more_mul_factor, limits->min_op_sys_clk_div); + dev_dbg(dev, "more_mul_factor: min_op_sys_clk_div: %d\n", + more_mul_factor); + i = ALIGN(more_mul_min, more_mul_factor); + if (!is_one_or_even(i)) + i <<= 1; + + dev_dbg(dev, "final more_mul: %d\n", i); + if (i > more_mul_max) { + dev_warn(dev, "final more_mul is bad, max %d", more_mul_max); + return -EINVAL; + } + + pll->pll_multiplier = mul * i; + pll->op_sys_clk_div = div * i / pll->pre_pll_clk_div; + dev_dbg(dev, "op_sys_clk_div: %d\n", pll->op_sys_clk_div); + + pll->pll_ip_clk_freq_hz = pll->ext_clk_freq_hz + / pll->pre_pll_clk_div; + + pll->pll_op_clk_freq_hz = pll->pll_ip_clk_freq_hz + * pll->pll_multiplier; + + /* Derive pll_op_clk_freq_hz. */ + pll->op_sys_clk_freq_hz = + pll->pll_op_clk_freq_hz / pll->op_sys_clk_div; + + pll->op_pix_clk_div = pll->bits_per_pixel; + dev_dbg(dev, "op_pix_clk_div: %d\n", pll->op_pix_clk_div); + + pll->op_pix_clk_freq_hz = + pll->op_sys_clk_freq_hz / pll->op_pix_clk_div; + + /* + * Some sensors perform analogue binning and some do this + * digitally. The ones doing this digitally can be roughly be + * found out using this formula. The ones doing this digitally + * should run at higher clock rate, so smaller divisor is used + * on video timing side. + */ + if (limits->min_line_length_pck_bin > limits->min_line_length_pck + / pll->binning_horizontal) + vt_op_binning_div = pll->binning_horizontal; + else + vt_op_binning_div = 1; + dev_dbg(dev, "vt_op_binning_div: %d\n", vt_op_binning_div); + + /* + * Profile 2 supports vt_pix_clk_div E [4, 10] + * + * Horizontal binning can be used as a base for difference in + * divisors. One must make sure that horizontal blanking is + * enough to accommodate the CSI-2 sync codes. + * + * Take scaling factor into account as well. + * + * Find absolute limits for the factor of vt divider. + */ + dev_dbg(dev, "scale_m: %d\n", pll->scale_m); + min_vt_div = DIV_ROUND_UP(pll->op_pix_clk_div * pll->op_sys_clk_div + * pll->scale_n, + lane_op_clock_ratio * vt_op_binning_div + * pll->scale_m); + + /* Find smallest and biggest allowed vt divisor. */ + dev_dbg(dev, "min_vt_div: %d\n", min_vt_div); + min_vt_div = max(min_vt_div, + DIV_ROUND_UP(pll->pll_op_clk_freq_hz, + limits->max_vt_pix_clk_freq_hz)); + dev_dbg(dev, "min_vt_div: max_vt_pix_clk_freq_hz: %d\n", + min_vt_div); + min_vt_div = max_t(uint32_t, min_vt_div, + limits->min_vt_pix_clk_div + * limits->min_vt_sys_clk_div); + dev_dbg(dev, "min_vt_div: min_vt_clk_div: %d\n", min_vt_div); + + max_vt_div = limits->max_vt_sys_clk_div * limits->max_vt_pix_clk_div; + dev_dbg(dev, "max_vt_div: %d\n", max_vt_div); + max_vt_div = min(max_vt_div, + DIV_ROUND_UP(pll->pll_op_clk_freq_hz, + limits->min_vt_pix_clk_freq_hz)); + dev_dbg(dev, "max_vt_div: min_vt_pix_clk_freq_hz: %d\n", + max_vt_div); + + /* + * Find limitsits for sys_clk_div. Not all values are possible + * with all values of pix_clk_div. + */ + min_sys_div = limits->min_vt_sys_clk_div; + dev_dbg(dev, "min_sys_div: %d\n", min_sys_div); + min_sys_div = max(min_sys_div, + DIV_ROUND_UP(min_vt_div, + limits->max_vt_pix_clk_div)); + dev_dbg(dev, "min_sys_div: max_vt_pix_clk_div: %d\n", min_sys_div); + min_sys_div = max(min_sys_div, + pll->pll_op_clk_freq_hz + / limits->max_vt_sys_clk_freq_hz); + dev_dbg(dev, "min_sys_div: max_pll_op_clk_freq_hz: %d\n", min_sys_div); + min_sys_div = clk_div_even_up(min_sys_div); + dev_dbg(dev, "min_sys_div: one or even: %d\n", min_sys_div); + + max_sys_div = limits->max_vt_sys_clk_div; + dev_dbg(dev, "max_sys_div: %d\n", max_sys_div); + max_sys_div = min(max_sys_div, + DIV_ROUND_UP(max_vt_div, + limits->min_vt_pix_clk_div)); + dev_dbg(dev, "max_sys_div: min_vt_pix_clk_div: %d\n", max_sys_div); + max_sys_div = min(max_sys_div, + DIV_ROUND_UP(pll->pll_op_clk_freq_hz, + limits->min_vt_pix_clk_freq_hz)); + dev_dbg(dev, "max_sys_div: min_vt_pix_clk_freq_hz: %d\n", max_sys_div); + + /* + * Find pix_div such that a legal pix_div * sys_div results + * into a value which is not smaller than div, the desired + * divisor. + */ + for (vt_div = min_vt_div; vt_div <= max_vt_div; + vt_div += 2 - (vt_div & 1)) { + for (sys_div = min_sys_div; + sys_div <= max_sys_div; + sys_div += 2 - (sys_div & 1)) { + int pix_div = DIV_ROUND_UP(vt_div, sys_div); + + if (pix_div < + limits->min_vt_pix_clk_div + || pix_div + > limits->max_vt_pix_clk_div) { + dev_dbg(dev, + "pix_div %d too small or too big (%d--%d)\n", + pix_div, + limits->min_vt_pix_clk_div, + limits->max_vt_pix_clk_div); + continue; + } + + /* Check if this one is better. */ + if (pix_div * sys_div + <= ALIGN(min_vt_div, best_pix_div)) + best_pix_div = pix_div; + } + if (best_pix_div < INT_MAX >> 1) + break; + } + + pll->vt_sys_clk_div = DIV_ROUND_UP(min_vt_div, best_pix_div); + pll->vt_pix_clk_div = best_pix_div; + + pll->vt_sys_clk_freq_hz = + pll->pll_op_clk_freq_hz / pll->vt_sys_clk_div; + pll->vt_pix_clk_freq_hz = + pll->vt_sys_clk_freq_hz / pll->vt_pix_clk_div; + + pll->pixel_rate_csi = + pll->op_pix_clk_freq_hz * lane_op_clock_ratio; + + print_pll(dev, pll); + + rval = bounds_check(dev, pll->pre_pll_clk_div, + limits->min_pre_pll_clk_div, + limits->max_pre_pll_clk_div, "pre_pll_clk_div"); + if (!rval) + rval = bounds_check( + dev, pll->pll_ip_clk_freq_hz, + limits->min_pll_ip_freq_hz, limits->max_pll_ip_freq_hz, + "pll_ip_clk_freq_hz"); + if (!rval) + rval = bounds_check( + dev, pll->pll_multiplier, + limits->min_pll_multiplier, limits->max_pll_multiplier, + "pll_multiplier"); + if (!rval) + rval = bounds_check( + dev, pll->pll_op_clk_freq_hz, + limits->min_pll_op_freq_hz, limits->max_pll_op_freq_hz, + "pll_op_clk_freq_hz"); + if (!rval) + rval = bounds_check( + dev, pll->op_sys_clk_div, + limits->min_op_sys_clk_div, limits->max_op_sys_clk_div, + "op_sys_clk_div"); + if (!rval) + rval = bounds_check( + dev, pll->op_pix_clk_div, + limits->min_op_pix_clk_div, limits->max_op_pix_clk_div, + "op_pix_clk_div"); + if (!rval) + rval = bounds_check( + dev, pll->op_sys_clk_freq_hz, + limits->min_op_sys_clk_freq_hz, + limits->max_op_sys_clk_freq_hz, + "op_sys_clk_freq_hz"); + if (!rval) + rval = bounds_check( + dev, pll->op_pix_clk_freq_hz, + limits->min_op_pix_clk_freq_hz, + limits->max_op_pix_clk_freq_hz, + "op_pix_clk_freq_hz"); + if (!rval) + rval = bounds_check( + dev, pll->vt_sys_clk_freq_hz, + limits->min_vt_sys_clk_freq_hz, + limits->max_vt_sys_clk_freq_hz, + "vt_sys_clk_freq_hz"); + if (!rval) + rval = bounds_check( + dev, pll->vt_pix_clk_freq_hz, + limits->min_vt_pix_clk_freq_hz, + limits->max_vt_pix_clk_freq_hz, + "vt_pix_clk_freq_hz"); + + return rval; +} +EXPORT_SYMBOL_GPL(smiapp_pll_calculate); + +MODULE_AUTHOR("Sakari Ailus <sakari.ai...@maxwell.research.nokia.com>"); +MODULE_DESCRIPTION("Generic SMIA/SMIA++ PLL calculator"); +MODULE_LICENSE("GPL"); diff --git a/drivers/media/video/smiapp-pll.h b/drivers/media/video/smiapp-pll.h new file mode 100644 index 0000000..9eab63f --- /dev/null +++ b/drivers/media/video/smiapp-pll.h @@ -0,0 +1,103 @@ +/* + * drivers/media/video/smiapp-pll.h + * + * Generic driver for SMIA/SMIA++ compliant camera modules + * + * Copyright (C) 2012 Nokia Corporation + * Contact: Sakari Ailus <sakari.ai...@maxwell.research.nokia.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * version 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA + * 02110-1301 USA + * + */ + +#ifndef SMIAPP_PLL_H +#define SMIAPP_PLL_H + +#include <linux/device.h> + +struct smiapp_pll { + uint8_t lanes; + uint8_t binning_horizontal; + uint8_t binning_vertical; + uint8_t scale_m; + uint8_t scale_n; + uint8_t bits_per_pixel; + uint16_t flags; + uint32_t link_freq; + + uint16_t pre_pll_clk_div; + uint16_t pll_multiplier; + uint16_t op_sys_clk_div; + uint16_t op_pix_clk_div; + uint16_t vt_sys_clk_div; + uint16_t vt_pix_clk_div; + + uint32_t ext_clk_freq_hz; + uint32_t pll_ip_clk_freq_hz; + uint32_t pll_op_clk_freq_hz; + uint32_t op_sys_clk_freq_hz; + uint32_t op_pix_clk_freq_hz; + uint32_t vt_sys_clk_freq_hz; + uint32_t vt_pix_clk_freq_hz; + + uint32_t pixel_rate_csi; +}; + +struct smiapp_pll_limits { + /* Strict PLL limits */ + uint32_t min_ext_clk_freq_hz; + uint32_t max_ext_clk_freq_hz; + uint16_t min_pre_pll_clk_div; + uint16_t max_pre_pll_clk_div; + uint32_t min_pll_ip_freq_hz; + uint32_t max_pll_ip_freq_hz; + uint16_t min_pll_multiplier; + uint16_t max_pll_multiplier; + uint32_t min_pll_op_freq_hz; + uint32_t max_pll_op_freq_hz; + + uint16_t min_vt_sys_clk_div; + uint16_t max_vt_sys_clk_div; + uint32_t min_vt_sys_clk_freq_hz; + uint32_t max_vt_sys_clk_freq_hz; + uint16_t min_vt_pix_clk_div; + uint16_t max_vt_pix_clk_div; + uint32_t min_vt_pix_clk_freq_hz; + uint32_t max_vt_pix_clk_freq_hz; + + uint16_t min_op_sys_clk_div; + uint16_t max_op_sys_clk_div; + uint32_t min_op_sys_clk_freq_hz; + uint32_t max_op_sys_clk_freq_hz; + uint16_t min_op_pix_clk_div; + uint16_t max_op_pix_clk_div; + uint32_t min_op_pix_clk_freq_hz; + uint32_t max_op_pix_clk_freq_hz; + + /* Other relevant limits */ + uint32_t min_line_length_pck_bin; + uint32_t min_line_length_pck; +}; + +/* op pix clock is for all lanes in total normally */ +#define SMIAPP_PLL_FLAG_OP_PIX_CLOCK_PER_LANE (1 << 0) +#define SMIAPP_PLL_FLAG_NO_OP_CLOCKS (1 << 1) + +struct device; + +int smiapp_pll_calculate(struct device *dev, struct smiapp_pll_limits *limits, + struct smiapp_pll *pll); + +#endif /* SMIAPP_PLL_H */ -- 1.7.2.5 -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html