/* * Allwinner SoCs SRAM Controller Driver * * Copyright (C) 2015 Maxime Ripard * * Author: Maxime Ripard <maxime.ripard@free-electrons.com> * * This file is licensed under the terms of the GNU General Public * License version 2. This program is licensed "as is" without any * warranty of any kind, whether express or implied. */ #include <linux/debugfs.h> #include <linux/io.h> #include <linux/module.h> #include <linux/of.h> #include <linux/of_address.h> #include <linux/of_device.h> #include <linux/platform_device.h> #include <linux/soc/sunxi/sunxi_sram.h> struct sunxi_sram_func { char *func; u8 val; }; struct sunxi_sram_data { char *name; u8 reg; u8 offset; u8 width; struct sunxi_sram_func *func; struct list_head list; }; struct sunxi_sram_desc { struct sunxi_sram_data data; bool claimed; }; #define SUNXI_SRAM_MAP(_val, _func) \ { \ .func = _func, \ .val = _val, \ } #define SUNXI_SRAM_DATA(_name, _reg, _off, _width, ...) \ { \ .name = _name, \ .reg = _reg, \ .offset = _off, \ .width = _width, \ .func = (struct sunxi_sram_func[]){ \ __VA_ARGS__, { } }, \ } static struct sunxi_sram_desc sun4i_a10_sram_a3_a4 = { .data = SUNXI_SRAM_DATA("A3-A4", 0x4, 0x4, 2, SUNXI_SRAM_MAP(0, "cpu"), SUNXI_SRAM_MAP(1, "emac")), }; static struct sunxi_sram_desc sun4i_a10_sram_d = { .data = SUNXI_SRAM_DATA("D", 0x4, 0x0, 1, SUNXI_SRAM_MAP(0, "cpu"), SUNXI_SRAM_MAP(1, "usb-otg")), }; static const struct of_device_id sunxi_sram_dt_ids[] = { { .compatible = "allwinner,sun4i-a10-sram-a3-a4", .data = &sun4i_a10_sram_a3_a4.data, }, { .compatible = "allwinner,sun4i-a10-sram-d", .data = &sun4i_a10_sram_d.data, }, {} }; static struct device *sram_dev; static LIST_HEAD(claimed_sram); static DEFINE_SPINLOCK(sram_lock); static void __iomem *base; static int sunxi_sram_show(struct seq_file *s, void *data) { struct device_node *sram_node, *section_node; const struct sunxi_sram_data *sram_data; const struct of_device_id *match; struct sunxi_sram_func *func; const __be32 *sram_addr_p, *section_addr_p; u32 val; seq_puts(s, "Allwinner sunXi SRAM\n"); seq_puts(s, "--------------------\n\n"); for_each_child_of_node(sram_dev->of_node, sram_node) { sram_addr_p = of_get_address(sram_node, 0, NULL, NULL); seq_printf(s, "sram@%08x\n", be32_to_cpu(*sram_addr_p)); for_each_child_of_node(sram_node, section_node) { match = of_match_node(sunxi_sram_dt_ids, section_node); if (!match) continue; sram_data = match->data; section_addr_p = of_get_address(section_node, 0, NULL, NULL); seq_printf(s, "\tsection@%04x\t(%s)\n", be32_to_cpu(*section_addr_p), sram_data->name); val = readl(base + sram_data->reg); val >>= sram_data->offset; val &= GENMASK(sram_data->width - 1, 0); for (func = sram_data->func; func->func; func++) { seq_printf(s, "\t\t%s%c\n", func->func, func->val == val ? '*' : ' '); } } seq_puts(s, "\n"); } return 0; } static int sunxi_sram_open(struct inode *inode, struct file *file) { return single_open(file, sunxi_sram_show, inode->i_private); } static const struct file_operations sunxi_sram_fops = { .open = sunxi_sram_open, .read = seq_read, .llseek = seq_lseek, .release = single_release, }; static inline struct sunxi_sram_desc *to_sram_desc(const struct sunxi_sram_data *data) { return container_of(data, struct sunxi_sram_desc, data); } static const struct sunxi_sram_data *sunxi_sram_of_parse(struct device_node *node, unsigned int *value) { const struct of_device_id *match; struct of_phandle_args args; int ret; ret = of_parse_phandle_with_fixed_args(node, "allwinner,sram", 1, 0, &args); if (ret) return ERR_PTR(ret); if (!of_device_is_available(args.np)) { ret = -EBUSY; goto err; } if (value) *value = args.args[0]; match = of_match_node(sunxi_sram_dt_ids, args.np); if (!match) { ret = -EINVAL; goto err; } of_node_put(args.np); return match->data; err: of_node_put(args.np); return ERR_PTR(ret); } int sunxi_sram_claim(struct device *dev) { const struct sunxi_sram_data *sram_data; struct sunxi_sram_desc *sram_desc; unsigned int device; u32 val, mask; if (IS_ERR(base)) return -EPROBE_DEFER; if (!dev || !dev->of_node) return -EINVAL; sram_data = sunxi_sram_of_parse(dev->of_node, &device); if (IS_ERR(sram_data)) return PTR_ERR(sram_data); sram_desc = to_sram_desc(sram_data); spin_lock(&sram_lock); if (sram_desc->claimed) { spin_unlock(&sram_lock); return -EBUSY; } mask = GENMASK(sram_data->offset + sram_data->width - 1, sram_data->offset); val = readl(base + sram_data->reg); val &= ~mask; writel(val | ((device << sram_data->offset) & mask), base + sram_data->reg); spin_unlock(&sram_lock); return 0; } EXPORT_SYMBOL(sunxi_sram_claim); int sunxi_sram_release(struct device *dev) { const struct sunxi_sram_data *sram_data; struct sunxi_sram_desc *sram_desc; if (!dev || !dev->of_node) return -EINVAL; sram_data = sunxi_sram_of_parse(dev->of_node, NULL); if (IS_ERR(sram_data)) return -EINVAL; sram_desc = to_sram_desc(sram_data); spin_lock(&sram_lock); sram_desc->claimed = false; spin_unlock(&sram_lock); return 0; } EXPORT_SYMBOL(sunxi_sram_release); static int sunxi_sram_probe(struct platform_device *pdev) { struct resource *res; struct dentry *d; sram_dev = &pdev->dev; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); base = devm_ioremap_resource(&pdev->dev, res); if (IS_ERR(base)) return PTR_ERR(base); of_platform_populate(pdev->dev.of_node, NULL, NULL, &pdev->dev); d = debugfs_create_file("sram", S_IRUGO, NULL, NULL, &sunxi_sram_fops); if (!d) return -ENOMEM; return 0; } static const struct of_device_id sunxi_sram_dt_match[] = { { .compatible = "allwinner,sun4i-a10-sram-controller" }, { }, }; MODULE_DEVICE_TABLE(of, sunxi_sram_dt_match); static struct platform_driver sunxi_sram_driver = { .driver = { .name = "sunxi-sram", .of_match_table = sunxi_sram_dt_match, }, .probe = sunxi_sram_probe, }; module_platform_driver(sunxi_sram_driver); MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>"); MODULE_DESCRIPTION("Allwinner sunXi SRAM Controller Driver"); MODULE_LICENSE("GPL");