diff options
Diffstat (limited to 'drivers/soc/sunxi')
-rw-r--r-- | drivers/soc/sunxi/Kconfig | 10 | ||||
-rw-r--r-- | drivers/soc/sunxi/Makefile | 1 | ||||
-rw-r--r-- | drivers/soc/sunxi/sunxi_sram.c | 284 |
3 files changed, 295 insertions, 0 deletions
diff --git a/drivers/soc/sunxi/Kconfig b/drivers/soc/sunxi/Kconfig new file mode 100644 index 000000000000..353b07e40176 --- /dev/null +++ b/drivers/soc/sunxi/Kconfig @@ -0,0 +1,10 @@ +# +# Allwinner sunXi SoC drivers +# +config SUNXI_SRAM + bool + default ARCH_SUNXI + help + Say y here to enable the SRAM controller support. This + device is responsible on mapping the SRAM in the sunXi SoCs + whether to the CPU/DMA, or to the devices. diff --git a/drivers/soc/sunxi/Makefile b/drivers/soc/sunxi/Makefile new file mode 100644 index 000000000000..4cf9dbdf346e --- /dev/null +++ b/drivers/soc/sunxi/Makefile @@ -0,0 +1 @@ +obj-$(CONFIG_SUNXI_SRAM) += sunxi_sram.o diff --git a/drivers/soc/sunxi/sunxi_sram.c b/drivers/soc/sunxi/sunxi_sram.c new file mode 100644 index 000000000000..bc52670c8f4b --- /dev/null +++ b/drivers/soc/sunxi/sunxi_sram.c @@ -0,0 +1,284 @@ +/* + * 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 &= sram_data->width; + + 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, 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"); |