/* * OpenFirmware helpers for memory drivers * * Copyright (C) 2012 Texas Instruments, Inc. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. */ #include <linux/device.h>#include <linux/platform_device.h>#include <linux/list.h>#include <linux/of.h>#include <linux/gfp.h>#include <memory/jedec_ddr.h>#include <linux/export.h> /** * of_get_min_tck() - extract min timing values for ddr * @np: pointer to ddr device tree node * @device: device requesting for min timing values * * Populates the lpddr2_min_tck structure by extracting data * from device tree node. Returns a pointer to the populated * structure. If any error in populating the structure, returns * default min timings provided by JEDEC. */const struct lpddr2_min_tck *of_get_min_tck(struct device_node *np,		struct device *dev){	int			ret = 0;	struct lpddr2_min_tck	*min; 	min = devm_kzalloc(dev, sizeof(*min), GFP_KERNEL);	if (!min)		goto default_min_tck; 	ret |= of_property_read_u32(np, "tRPab-min-tck", &min->tRPab);	ret |= of_property_read_u32(np, "tRCD-min-tck", &min->tRCD);	ret |= of_property_read_u32(np, "tWR-min-tck", &min->tWR);	ret |= of_property_read_u32(np, "tRASmin-min-tck", &min->tRASmin);	ret |= of_property_read_u32(np, "tRRD-min-tck", &min->tRRD);	ret |= of_property_read_u32(np, "tWTR-min-tck", &min->tWTR);	ret |= of_property_read_u32(np, "tXP-min-tck", &min->tXP);	ret |= of_property_read_u32(np, "tRTP-min-tck", &min->tRTP);	ret |= of_property_read_u32(np, "tCKE-min-tck", &min->tCKE);	ret |= of_property_read_u32(np, "tCKESR-min-tck", &min->tCKESR);	ret |= of_property_read_u32(np, "tFAW-min-tck", &min->tFAW); 	if (ret) {		devm_kfree(dev, min);		goto default_min_tck;	} 	return min; default_min_tck:	dev_warn(dev, "%s: using default min-tck values\n", __func__);	return &lpddr2_jedec_min_tck;}EXPORT_SYMBOL(of_get_min_tck); static int of_do_get_timings(struct device_node *np,		struct lpddr2_timings *tim){	int ret; 	ret = of_property_read_u32(np, "max-freq", &tim->max_freq);	ret |= of_property_read_u32(np, "min-freq", &tim->min_freq);	ret |= of_property_read_u32(np, "tRPab", &tim->tRPab);	ret |= of_property_read_u32(np, "tRCD", &tim->tRCD);	ret |= of_property_read_u32(np, "tWR", &tim->tWR);	ret |= of_property_read_u32(np, "tRAS-min", &tim->tRAS_min);	ret |= of_property_read_u32(np, "tRRD", &tim->tRRD);	ret |= of_property_read_u32(np, "tWTR", &tim->tWTR);	ret |= of_property_read_u32(np, "tXP", &tim->tXP);	ret |= of_property_read_u32(np, "tRTP", &tim->tRTP);	ret |= of_property_read_u32(np, "tCKESR", &tim->tCKESR);	ret |= of_property_read_u32(np, "tDQSCK-max", &tim->tDQSCK_max);	ret |= of_property_read_u32(np, "tFAW", &tim->tFAW);	ret |= of_property_read_u32(np, "tZQCS", &tim->tZQCS);	ret |= of_property_read_u32(np, "tZQCL", &tim->tZQCL);	ret |= of_property_read_u32(np, "tZQinit", &tim->tZQinit);	ret |= of_property_read_u32(np, "tRAS-max-ns", &tim->tRAS_max_ns);	ret |= of_property_read_u32(np, "tDQSCK-max-derated",		&tim->tDQSCK_max_derated); 	return ret;} /** * of_get_ddr_timings() - extracts the ddr timings and updates no of * frequencies available. * @np_ddr: Pointer to ddr device tree node * @dev: Device requesting for ddr timings * @device_type: Type of ddr(LPDDR2 S2/S4) * @nr_frequencies: No of frequencies available for ddr * (updated by this function) * * Populates lpddr2_timings structure by extracting data from device * tree node. Returns pointer to populated structure. If any error * while populating, returns default timings provided by JEDEC. */const struct lpddr2_timings *of_get_ddr_timings(struct device_node *np_ddr,		struct device *dev, u32 device_type, u32 *nr_frequencies){	struct lpddr2_timings	*timings = NULL;	u32			arr_sz = 0, i = 0;	struct device_node	*np_tim;	char			*tim_compat = NULL; 	switch (device_type) {	case DDR_TYPE_LPDDR2_S2:	case DDR_TYPE_LPDDR2_S4:		tim_compat = "jedec,lpddr2-timings";		break;	default:		dev_warn(dev, "%s: un-supported memory type\n", __func__);	} 	for_each_child_of_node(np_ddr, np_tim)		if (of_device_is_compatible(np_tim, tim_compat))			arr_sz++; 	if (arr_sz)		timings = devm_kzalloc(dev, sizeof(*timings) * arr_sz,			GFP_KERNEL); 	if (!timings)		goto default_timings; 	for_each_child_of_node(np_ddr, np_tim) {		if (of_device_is_compatible(np_tim, tim_compat)) {			if (of_do_get_timings(np_tim, &timings[i])) {				devm_kfree(dev, timings);				goto default_timings;			}			i++;		}	} 	*nr_frequencies = arr_sz; 	return timings; default_timings:	dev_warn(dev, "%s: using default timings\n", __func__);	*nr_frequencies = ARRAY_SIZE(lpddr2_jedec_timings);	return lpddr2_jedec_timings;}EXPORT_SYMBOL(of_get_ddr_timings);