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1// SPDX-License-Identifier: GPL-2.02/*3 * Copyright (c) 2020, NVIDIA CORPORATION. All rights reserved.4 */5 6#include <linux/of_reserved_mem.h>7 8#include "tegra210-emc.h"9 10#define TEGRA_EMC_MAX_FREQS 1611 12static int tegra210_emc_table_device_init(struct reserved_mem *rmem,13 struct device *dev)14{15 struct tegra210_emc *emc = dev_get_drvdata(dev);16 struct tegra210_emc_timing *timings;17 unsigned int i, count = 0;18 19 timings = memremap(rmem->base, rmem->size, MEMREMAP_WB);20 if (!timings) {21 dev_err(dev, "failed to map EMC table\n");22 return -ENOMEM;23 }24 25 for (i = 0; i < TEGRA_EMC_MAX_FREQS; i++) {26 if (timings[i].revision == 0)27 break;28 29 count++;30 }31 32 /* only the nominal and derated tables are expected */33 if (emc->derated) {34 dev_warn(dev, "excess EMC table '%s'\n", rmem->name);35 goto out;36 }37 38 if (emc->nominal) {39 if (count != emc->num_timings) {40 dev_warn(dev, "%u derated vs. %u nominal entries\n",41 count, emc->num_timings);42 memunmap(timings);43 return -EINVAL;44 }45 46 emc->derated = timings;47 } else {48 emc->num_timings = count;49 emc->nominal = timings;50 }51 52out:53 /* keep track of which table this is */54 rmem->priv = timings;55 56 return 0;57}58 59static void tegra210_emc_table_device_release(struct reserved_mem *rmem,60 struct device *dev)61{62 struct tegra210_emc_timing *timings = rmem->priv;63 struct tegra210_emc *emc = dev_get_drvdata(dev);64 65 if ((emc->nominal && timings != emc->nominal) &&66 (emc->derated && timings != emc->derated))67 dev_warn(dev, "trying to release unassigned EMC table '%s'\n",68 rmem->name);69 70 memunmap(timings);71}72 73static const struct reserved_mem_ops tegra210_emc_table_ops = {74 .device_init = tegra210_emc_table_device_init,75 .device_release = tegra210_emc_table_device_release,76};77 78static int tegra210_emc_table_init(struct reserved_mem *rmem)79{80 pr_debug("Tegra210 EMC table at %pa, size %lu bytes\n", &rmem->base,81 (unsigned long)rmem->size);82 83 rmem->ops = &tegra210_emc_table_ops;84 85 return 0;86}87RESERVEDMEM_OF_DECLARE(tegra210_emc_table, "nvidia,tegra210-emc-table",88 tegra210_emc_table_init);89