From 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 Mon Sep 17 00:00:00 2001 From: Yunhong Jiang Date: Tue, 4 Aug 2015 12:17:53 -0700 Subject: Add the rt linux 4.1.3-rt3 as base Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang --- kernel/drivers/misc/sram.c | 239 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 239 insertions(+) create mode 100644 kernel/drivers/misc/sram.c (limited to 'kernel/drivers/misc/sram.c') diff --git a/kernel/drivers/misc/sram.c b/kernel/drivers/misc/sram.c new file mode 100644 index 000000000..eeaaf5fca --- /dev/null +++ b/kernel/drivers/misc/sram.c @@ -0,0 +1,239 @@ +/* + * Generic on-chip SRAM allocation driver + * + * Copyright (C) 2012 Philipp Zabel, Pengutronix + * + * 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. + * 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 Street, Fifth Floor, Boston, + * MA 02110-1301, USA. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define SRAM_GRANULARITY 32 + +struct sram_dev { + struct gen_pool *pool; + struct clk *clk; +}; + +struct sram_reserve { + struct list_head list; + u32 start; + u32 size; +}; + +static int sram_reserve_cmp(void *priv, struct list_head *a, + 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_probe(struct platform_device *pdev) +{ + void __iomem *virt_base; + struct sram_dev *sram; + struct resource *res; + struct device_node *np = pdev->dev.of_node, *child; + unsigned long size, cur_start, cur_size; + struct sram_reserve *rblocks, *block; + struct list_head reserve_list; + unsigned int nblocks; + int ret; + + INIT_LIST_HEAD(&reserve_list); + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) { + dev_err(&pdev->dev, "found no memory resource\n"); + return -EINVAL; + } + + size = resource_size(res); + + if (!devm_request_mem_region(&pdev->dev, + res->start, size, pdev->name)) { + dev_err(&pdev->dev, "could not request region for resource\n"); + return -EBUSY; + } + + virt_base = devm_ioremap_wc(&pdev->dev, res->start, size); + if (IS_ERR(virt_base)) + return PTR_ERR(virt_base); + + sram = devm_kzalloc(&pdev->dev, sizeof(*sram), GFP_KERNEL); + if (!sram) + return -ENOMEM; + + sram->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(sram->clk)) + sram->clk = NULL; + else + clk_prepare_enable(sram->clk); + + sram->pool = devm_gen_pool_create(&pdev->dev, ilog2(SRAM_GRANULARITY), -1); + if (!sram->pool) + return -ENOMEM; + + /* + * 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 = kmalloc((nblocks) * sizeof(*rblocks), GFP_KERNEL); + if (!rblocks) { + ret = -ENOMEM; + goto err_alloc; + } + + 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(&pdev->dev, + "could not get address for node %s\n", + child->full_name); + goto err_chunks; + } + + if (child_res.start < res->start || child_res.end > res->end) { + dev_err(&pdev->dev, + "reserved block %s outside the sram area\n", + child->full_name); + 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); + + dev_dbg(&pdev->dev, "found reserved block 0x%x-0x%x\n", + block->start, + block->start + block->size); + + block++; + } + + /* 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); + + cur_start = 0; + + list_for_each_entry(block, &reserve_list, list) { + /* can only happen if sections overlap */ + if (block->start < cur_start) { + dev_err(&pdev->dev, + "block at 0x%x starts after current offset 0x%lx\n", + block->start, cur_start); + ret = -EINVAL; + 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(&pdev->dev, "adding chunk 0x%lx-0x%lx\n", + cur_start, cur_start + cur_size); + ret = gen_pool_add_virt(sram->pool, + (unsigned long)virt_base + cur_start, + res->start + cur_start, cur_size, -1); + if (ret < 0) + goto err_chunks; + + /* next allocation after this reserved block */ + cur_start = block->start + block->size; + } + + kfree(rblocks); + + platform_set_drvdata(pdev, sram); + + dev_dbg(&pdev->dev, "SRAM pool: %ld KiB @ 0x%p\n", size / 1024, virt_base); + + return 0; + +err_chunks: + kfree(rblocks); +err_alloc: + 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); + + if (gen_pool_avail(sram->pool) < gen_pool_size(sram->pool)) + dev_dbg(&pdev->dev, "removed while SRAM allocated\n"); + + if (sram->clk) + clk_disable_unprepare(sram->clk); + + return 0; +} + +#ifdef CONFIG_OF +static const struct of_device_id sram_dt_ids[] = { + { .compatible = "mmio-sram" }, + {} +}; +#endif + +static struct platform_driver sram_driver = { + .driver = { + .name = "sram", + .of_match_table = of_match_ptr(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); -- cgit 1.2.3-korg