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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
commit | 5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch) | |
tree | a94efe259b9009378be6d90eb30d2b019d95c194 /drivers/misc/sram.c | |
parent | Initial commit. (diff) | |
download | linux-upstream/5.10.209.tar.xz linux-upstream/5.10.209.zip |
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/misc/sram.c')
-rw-r--r-- | drivers/misc/sram.c | 429 |
1 files changed, 429 insertions, 0 deletions
diff --git a/drivers/misc/sram.c b/drivers/misc/sram.c new file mode 100644 index 000000000..202bf951e --- /dev/null +++ b/drivers/misc/sram.c @@ -0,0 +1,429 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Generic on-chip SRAM allocation driver + * + * Copyright (C) 2012 Philipp Zabel, Pengutronix + */ + +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/genalloc.h> +#include <linux/io.h> +#include <linux/list_sort.h> +#include <linux/of_address.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> +#include <linux/slab.h> +#include <linux/mfd/syscon.h> +#include <soc/at91/atmel-secumod.h> + +#include "sram.h" + +#define SRAM_GRANULARITY 32 + +static ssize_t sram_read(struct file *filp, struct kobject *kobj, + struct bin_attribute *attr, + char *buf, loff_t pos, size_t count) +{ + struct sram_partition *part; + + part = container_of(attr, struct sram_partition, battr); + + mutex_lock(&part->lock); + memcpy_fromio(buf, part->base + pos, count); + mutex_unlock(&part->lock); + + return count; +} + +static ssize_t sram_write(struct file *filp, struct kobject *kobj, + struct bin_attribute *attr, + char *buf, loff_t pos, size_t count) +{ + struct sram_partition *part; + + part = container_of(attr, struct sram_partition, battr); + + mutex_lock(&part->lock); + memcpy_toio(part->base + pos, buf, count); + mutex_unlock(&part->lock); + + return count; +} + +static int sram_add_pool(struct sram_dev *sram, struct sram_reserve *block, + phys_addr_t start, struct sram_partition *part) +{ + int ret; + + part->pool = devm_gen_pool_create(sram->dev, ilog2(SRAM_GRANULARITY), + NUMA_NO_NODE, block->label); + if (IS_ERR(part->pool)) + return PTR_ERR(part->pool); + + ret = gen_pool_add_virt(part->pool, (unsigned long)part->base, start, + block->size, NUMA_NO_NODE); + if (ret < 0) { + dev_err(sram->dev, "failed to register subpool: %d\n", ret); + return ret; + } + + return 0; +} + +static int sram_add_export(struct sram_dev *sram, struct sram_reserve *block, + phys_addr_t start, struct sram_partition *part) +{ + sysfs_bin_attr_init(&part->battr); + part->battr.attr.name = devm_kasprintf(sram->dev, GFP_KERNEL, + "%llx.sram", + (unsigned long long)start); + if (!part->battr.attr.name) + return -ENOMEM; + + part->battr.attr.mode = S_IRUSR | S_IWUSR; + part->battr.read = sram_read; + part->battr.write = sram_write; + part->battr.size = block->size; + + return device_create_bin_file(sram->dev, &part->battr); +} + +static int sram_add_partition(struct sram_dev *sram, struct sram_reserve *block, + phys_addr_t start) +{ + int ret; + struct sram_partition *part = &sram->partition[sram->partitions]; + + mutex_init(&part->lock); + part->base = sram->virt_base + block->start; + + if (block->pool) { + ret = sram_add_pool(sram, block, start, part); + if (ret) + return ret; + } + if (block->export) { + ret = sram_add_export(sram, block, start, part); + if (ret) + return ret; + } + if (block->protect_exec) { + ret = sram_check_protect_exec(sram, block, part); + if (ret) + return ret; + + ret = sram_add_pool(sram, block, start, part); + if (ret) + return ret; + + sram_add_protect_exec(part); + } + + sram->partitions++; + + return 0; +} + +static void sram_free_partitions(struct sram_dev *sram) +{ + struct sram_partition *part; + + if (!sram->partitions) + return; + + part = &sram->partition[sram->partitions - 1]; + for (; sram->partitions; sram->partitions--, part--) { + if (part->battr.size) + device_remove_bin_file(sram->dev, &part->battr); + + if (part->pool && + gen_pool_avail(part->pool) < gen_pool_size(part->pool)) + dev_err(sram->dev, "removed pool while SRAM allocated\n"); + } +} + +static int sram_reserve_cmp(void *priv, const struct list_head *a, + const struct list_head *b) +{ + struct sram_reserve *ra = list_entry(a, struct sram_reserve, list); + struct sram_reserve *rb = list_entry(b, struct sram_reserve, list); + + return ra->start - rb->start; +} + +static int sram_reserve_regions(struct sram_dev *sram, struct resource *res) +{ + struct device_node *np = sram->dev->of_node, *child; + unsigned long size, cur_start, cur_size; + struct sram_reserve *rblocks, *block; + struct list_head reserve_list; + unsigned int nblocks, exports = 0; + const char *label; + int ret = 0; + + INIT_LIST_HEAD(&reserve_list); + + size = resource_size(res); + + /* + * We need an additional block to mark the end of the memory region + * after the reserved blocks from the dt are processed. + */ + nblocks = (np) ? of_get_available_child_count(np) + 1 : 1; + rblocks = kcalloc(nblocks, sizeof(*rblocks), GFP_KERNEL); + if (!rblocks) + return -ENOMEM; + + block = &rblocks[0]; + for_each_available_child_of_node(np, child) { + struct resource child_res; + + ret = of_address_to_resource(child, 0, &child_res); + if (ret < 0) { + dev_err(sram->dev, + "could not get address for node %pOF\n", + child); + goto err_chunks; + } + + if (child_res.start < res->start || child_res.end > res->end) { + dev_err(sram->dev, + "reserved block %pOF outside the sram area\n", + child); + ret = -EINVAL; + goto err_chunks; + } + + block->start = child_res.start - res->start; + block->size = resource_size(&child_res); + list_add_tail(&block->list, &reserve_list); + + if (of_find_property(child, "export", NULL)) + block->export = true; + + if (of_find_property(child, "pool", NULL)) + block->pool = true; + + if (of_find_property(child, "protect-exec", NULL)) + block->protect_exec = true; + + if ((block->export || block->pool || block->protect_exec) && + block->size) { + exports++; + + label = NULL; + ret = of_property_read_string(child, "label", &label); + if (ret && ret != -EINVAL) { + dev_err(sram->dev, + "%pOF has invalid label name\n", + child); + goto err_chunks; + } + if (!label) + label = child->name; + + block->label = devm_kstrdup(sram->dev, + label, GFP_KERNEL); + if (!block->label) { + ret = -ENOMEM; + goto err_chunks; + } + + dev_dbg(sram->dev, "found %sblock '%s' 0x%x-0x%x\n", + block->export ? "exported " : "", block->label, + block->start, block->start + block->size); + } else { + dev_dbg(sram->dev, "found reserved block 0x%x-0x%x\n", + block->start, block->start + block->size); + } + + block++; + } + child = NULL; + + /* the last chunk marks the end of the region */ + rblocks[nblocks - 1].start = size; + rblocks[nblocks - 1].size = 0; + list_add_tail(&rblocks[nblocks - 1].list, &reserve_list); + + list_sort(NULL, &reserve_list, sram_reserve_cmp); + + if (exports) { + sram->partition = devm_kcalloc(sram->dev, + exports, sizeof(*sram->partition), + GFP_KERNEL); + if (!sram->partition) { + ret = -ENOMEM; + goto err_chunks; + } + } + + cur_start = 0; + list_for_each_entry(block, &reserve_list, list) { + /* can only happen if sections overlap */ + if (block->start < cur_start) { + dev_err(sram->dev, + "block at 0x%x starts after current offset 0x%lx\n", + block->start, cur_start); + ret = -EINVAL; + sram_free_partitions(sram); + goto err_chunks; + } + + if ((block->export || block->pool || block->protect_exec) && + block->size) { + ret = sram_add_partition(sram, block, + res->start + block->start); + if (ret) { + sram_free_partitions(sram); + goto err_chunks; + } + } + + /* current start is in a reserved block, so continue after it */ + if (block->start == cur_start) { + cur_start = block->start + block->size; + continue; + } + + /* + * allocate the space between the current starting + * address and the following reserved block, or the + * end of the region. + */ + cur_size = block->start - cur_start; + + dev_dbg(sram->dev, "adding chunk 0x%lx-0x%lx\n", + cur_start, cur_start + cur_size); + + ret = gen_pool_add_virt(sram->pool, + (unsigned long)sram->virt_base + cur_start, + res->start + cur_start, cur_size, -1); + if (ret < 0) { + sram_free_partitions(sram); + goto err_chunks; + } + + /* next allocation after this reserved block */ + cur_start = block->start + block->size; + } + +err_chunks: + of_node_put(child); + kfree(rblocks); + + return ret; +} + +static int atmel_securam_wait(void) +{ + struct regmap *regmap; + u32 val; + + regmap = syscon_regmap_lookup_by_compatible("atmel,sama5d2-secumod"); + if (IS_ERR(regmap)) + return -ENODEV; + + return regmap_read_poll_timeout(regmap, AT91_SECUMOD_RAMRDY, val, + val & AT91_SECUMOD_RAMRDY_READY, + 10000, 500000); +} + +static const struct of_device_id sram_dt_ids[] = { + { .compatible = "mmio-sram" }, + { .compatible = "atmel,sama5d2-securam", .data = atmel_securam_wait }, + {} +}; + +static int sram_probe(struct platform_device *pdev) +{ + struct sram_dev *sram; + int ret; + int (*init_func)(void); + + sram = devm_kzalloc(&pdev->dev, sizeof(*sram), GFP_KERNEL); + if (!sram) + return -ENOMEM; + + sram->dev = &pdev->dev; + + if (of_property_read_bool(pdev->dev.of_node, "no-memory-wc")) + sram->virt_base = devm_platform_ioremap_resource(pdev, 0); + else + sram->virt_base = devm_platform_ioremap_resource_wc(pdev, 0); + if (IS_ERR(sram->virt_base)) { + dev_err(&pdev->dev, "could not map SRAM registers\n"); + return PTR_ERR(sram->virt_base); + } + + sram->pool = devm_gen_pool_create(sram->dev, ilog2(SRAM_GRANULARITY), + NUMA_NO_NODE, NULL); + if (IS_ERR(sram->pool)) + return PTR_ERR(sram->pool); + + sram->clk = devm_clk_get(sram->dev, NULL); + if (IS_ERR(sram->clk)) + sram->clk = NULL; + else + clk_prepare_enable(sram->clk); + + ret = sram_reserve_regions(sram, + platform_get_resource(pdev, IORESOURCE_MEM, 0)); + if (ret) + goto err_disable_clk; + + platform_set_drvdata(pdev, sram); + + init_func = of_device_get_match_data(&pdev->dev); + if (init_func) { + ret = init_func(); + if (ret) + goto err_free_partitions; + } + + dev_dbg(sram->dev, "SRAM pool: %zu KiB @ 0x%p\n", + gen_pool_size(sram->pool) / 1024, sram->virt_base); + + return 0; + +err_free_partitions: + sram_free_partitions(sram); +err_disable_clk: + if (sram->clk) + clk_disable_unprepare(sram->clk); + + return ret; +} + +static int sram_remove(struct platform_device *pdev) +{ + struct sram_dev *sram = platform_get_drvdata(pdev); + + sram_free_partitions(sram); + + if (gen_pool_avail(sram->pool) < gen_pool_size(sram->pool)) + dev_err(sram->dev, "removed while SRAM allocated\n"); + + if (sram->clk) + clk_disable_unprepare(sram->clk); + + return 0; +} + +static struct platform_driver sram_driver = { + .driver = { + .name = "sram", + .of_match_table = sram_dt_ids, + }, + .probe = sram_probe, + .remove = sram_remove, +}; + +static int __init sram_init(void) +{ + return platform_driver_register(&sram_driver); +} + +postcore_initcall(sram_init); |