| /* |
| * Device tree helpers for DMA request / controller |
| * |
| * Based on of_gpio.c |
| * |
| * Copyright (C) 2012 Texas Instruments Incorporated - http://www.ti.com/ |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 as |
| * published by the Free Software Foundation. |
| */ |
| |
| #include <linux/device.h> |
| #include <linux/err.h> |
| #include <linux/module.h> |
| #include <linux/mutex.h> |
| #include <linux/slab.h> |
| #include <linux/of.h> |
| #include <linux/of_dma.h> |
| |
| static LIST_HEAD(of_dma_list); |
| static DEFINE_MUTEX(of_dma_lock); |
| |
| /** |
| * of_dma_find_controller - Get a DMA controller in DT DMA helpers list |
| * @dma_spec: pointer to DMA specifier as found in the device tree |
| * |
| * Finds a DMA controller with matching device node and number for dma cells |
| * in a list of registered DMA controllers. If a match is found a valid pointer |
| * to the DMA data stored is retuned. A NULL pointer is returned if no match is |
| * found. |
| */ |
| static struct of_dma *of_dma_find_controller(struct of_phandle_args *dma_spec) |
| { |
| struct of_dma *ofdma; |
| |
| list_for_each_entry(ofdma, &of_dma_list, of_dma_controllers) |
| if (ofdma->of_node == dma_spec->np) |
| return ofdma; |
| |
| pr_debug("%s: can't find DMA controller %s\n", __func__, |
| dma_spec->np->full_name); |
| |
| return NULL; |
| } |
| |
| /** |
| * of_dma_router_xlate - translation function for router devices |
| * @dma_spec: pointer to DMA specifier as found in the device tree |
| * @of_dma: pointer to DMA controller data (router information) |
| * |
| * The function creates new dma_spec to be passed to the router driver's |
| * of_dma_route_allocate() function to prepare a dma_spec which will be used |
| * to request channel from the real DMA controller. |
| */ |
| static struct dma_chan *of_dma_router_xlate(struct of_phandle_args *dma_spec, |
| struct of_dma *ofdma) |
| { |
| struct dma_chan *chan; |
| struct of_dma *ofdma_target; |
| struct of_phandle_args dma_spec_target; |
| void *route_data; |
| |
| /* translate the request for the real DMA controller */ |
| memcpy(&dma_spec_target, dma_spec, sizeof(dma_spec_target)); |
| route_data = ofdma->of_dma_route_allocate(&dma_spec_target, ofdma); |
| if (IS_ERR(route_data)) |
| return NULL; |
| |
| ofdma_target = of_dma_find_controller(&dma_spec_target); |
| if (!ofdma_target) |
| return NULL; |
| |
| chan = ofdma_target->of_dma_xlate(&dma_spec_target, ofdma_target); |
| if (chan) { |
| chan->router = ofdma->dma_router; |
| chan->route_data = route_data; |
| } else { |
| ofdma->dma_router->route_free(ofdma->dma_router->dev, |
| route_data); |
| } |
| |
| /* |
| * Need to put the node back since the ofdma->of_dma_route_allocate |
| * has taken it for generating the new, translated dma_spec |
| */ |
| of_node_put(dma_spec_target.np); |
| return chan; |
| } |
| |
| /** |
| * of_dma_controller_register - Register a DMA controller to DT DMA helpers |
| * @np: device node of DMA controller |
| * @of_dma_xlate: translation function which converts a phandle |
| * arguments list into a dma_chan structure |
| * @data pointer to controller specific data to be used by |
| * translation function |
| * |
| * Returns 0 on success or appropriate errno value on error. |
| * |
| * Allocated memory should be freed with appropriate of_dma_controller_free() |
| * call. |
| */ |
| int of_dma_controller_register(struct device_node *np, |
| struct dma_chan *(*of_dma_xlate) |
| (struct of_phandle_args *, struct of_dma *), |
| void *data) |
| { |
| struct of_dma *ofdma; |
| |
| if (!np || !of_dma_xlate) { |
| pr_err("%s: not enough information provided\n", __func__); |
| return -EINVAL; |
| } |
| |
| ofdma = kzalloc(sizeof(*ofdma), GFP_KERNEL); |
| if (!ofdma) |
| return -ENOMEM; |
| |
| ofdma->of_node = np; |
| ofdma->of_dma_xlate = of_dma_xlate; |
| ofdma->of_dma_data = data; |
| |
| /* Now queue of_dma controller structure in list */ |
| mutex_lock(&of_dma_lock); |
| list_add_tail(&ofdma->of_dma_controllers, &of_dma_list); |
| mutex_unlock(&of_dma_lock); |
| |
| return 0; |
| } |
| EXPORT_SYMBOL_GPL(of_dma_controller_register); |
| |
| /** |
| * of_dma_controller_free - Remove a DMA controller from DT DMA helpers list |
| * @np: device node of DMA controller |
| * |
| * Memory allocated by of_dma_controller_register() is freed here. |
| */ |
| void of_dma_controller_free(struct device_node *np) |
| { |
| struct of_dma *ofdma; |
| |
| mutex_lock(&of_dma_lock); |
| |
| list_for_each_entry(ofdma, &of_dma_list, of_dma_controllers) |
| if (ofdma->of_node == np) { |
| list_del(&ofdma->of_dma_controllers); |
| kfree(ofdma); |
| break; |
| } |
| |
| mutex_unlock(&of_dma_lock); |
| } |
| EXPORT_SYMBOL_GPL(of_dma_controller_free); |
| |
| /** |
| * of_dma_router_register - Register a DMA router to DT DMA helpers as a |
| * controller |
| * @np: device node of DMA router |
| * @of_dma_route_allocate: setup function for the router which need to |
| * modify the dma_spec for the DMA controller to |
| * use and to set up the requested route. |
| * @dma_router: pointer to dma_router structure to be used when |
| * the route need to be free up. |
| * |
| * Returns 0 on success or appropriate errno value on error. |
| * |
| * Allocated memory should be freed with appropriate of_dma_controller_free() |
| * call. |
| */ |
| int of_dma_router_register(struct device_node *np, |
| void *(*of_dma_route_allocate) |
| (struct of_phandle_args *, struct of_dma *), |
| struct dma_router *dma_router) |
| { |
| struct of_dma *ofdma; |
| |
| if (!np || !of_dma_route_allocate || !dma_router) { |
| pr_err("%s: not enough information provided\n", __func__); |
| return -EINVAL; |
| } |
| |
| ofdma = kzalloc(sizeof(*ofdma), GFP_KERNEL); |
| if (!ofdma) |
| return -ENOMEM; |
| |
| ofdma->of_node = np; |
| ofdma->of_dma_xlate = of_dma_router_xlate; |
| ofdma->of_dma_route_allocate = of_dma_route_allocate; |
| ofdma->dma_router = dma_router; |
| |
| /* Now queue of_dma controller structure in list */ |
| mutex_lock(&of_dma_lock); |
| list_add_tail(&ofdma->of_dma_controllers, &of_dma_list); |
| mutex_unlock(&of_dma_lock); |
| |
| return 0; |
| } |
| EXPORT_SYMBOL_GPL(of_dma_router_register); |
| |
| /** |
| * of_dma_match_channel - Check if a DMA specifier matches name |
| * @np: device node to look for DMA channels |
| * @name: channel name to be matched |
| * @index: index of DMA specifier in list of DMA specifiers |
| * @dma_spec: pointer to DMA specifier as found in the device tree |
| * |
| * Check if the DMA specifier pointed to by the index in a list of DMA |
| * specifiers, matches the name provided. Returns 0 if the name matches and |
| * a valid pointer to the DMA specifier is found. Otherwise returns -ENODEV. |
| */ |
| static int of_dma_match_channel(struct device_node *np, const char *name, |
| int index, struct of_phandle_args *dma_spec) |
| { |
| const char *s; |
| |
| if (of_property_read_string_index(np, "dma-names", index, &s)) |
| return -ENODEV; |
| |
| if (strcmp(name, s)) |
| return -ENODEV; |
| |
| if (of_parse_phandle_with_args(np, "dmas", "#dma-cells", index, |
| dma_spec)) |
| return -ENODEV; |
| |
| return 0; |
| } |
| |
| /** |
| * of_dma_get_mcode_addr - Get the DMA micro code buffer address. |
| * @np: device node of DMA controller |
| * |
| * Return the physical address. |
| */ |
| unsigned int of_dma_get_mcode_addr(struct device_node *np) |
| { |
| unsigned int addr = 0; |
| const __be32 *prop; |
| |
| prop = of_get_property(np, "#dma-mcode-addr", NULL); |
| if (prop) |
| addr = be32_to_cpup(prop); |
| |
| return addr; |
| } |
| EXPORT_SYMBOL_GPL(of_dma_get_mcode_addr); |
| |
| /** |
| * of_dma_secure_dma_ch- Get the DMA micro code buffer address. |
| * @np: device node of DMA controller |
| * |
| * Return the physical address. |
| */ |
| bool of_dma_secure_mode(struct device_node *np) |
| { |
| bool ret = 0; |
| const __be32 *prop; |
| |
| prop = of_get_property(np, "#dma-secure-mode", NULL); |
| if (prop) |
| ret = be32_to_cpup(prop); |
| |
| return ret; |
| } |
| EXPORT_SYMBOL_GPL(of_dma_secure_mode); |
| |
| #ifdef CONFIG_SOC_EXYNOS8895 |
| void __iomem *of_dma_get_sel_chan_address(struct device_node *np) |
| { |
| const __be32 *reg_list; |
| int ret = 0; |
| |
| reg_list = of_get_property(np, "dma-selchan", NULL); |
| |
| if (!reg_list) |
| return NULL; |
| |
| ret = be32_to_cpup(reg_list); |
| if (!ret) |
| return NULL; |
| |
| return ioremap(ret, SZ_32); |
| } |
| EXPORT_SYMBOL_GPL(of_dma_get_sel_chan_address); |
| #endif |
| |
| /** |
| * of_dma_get_arwrapper_address - Get the DMA WAPPER AR address |
| * @np: device node of DMA controller |
| * @num: DMA channel thread number |
| * |
| * Return the virtual address. |
| */ |
| void __iomem *of_dma_get_arwrapper_address(struct device_node *np, unsigned int num) |
| { |
| const __be32 *reg_list; |
| unsigned int length, count; |
| |
| reg_list = of_get_property(np, "dma-arwrapper", &length); |
| count = (unsigned int)(length / sizeof(unsigned int)); |
| |
| if (!reg_list || num >= count) |
| return NULL; |
| |
| return ioremap(be32_to_cpup(reg_list + num), SZ_32); |
| } |
| EXPORT_SYMBOL_GPL(of_dma_get_arwrapper_address); |
| |
| /** |
| * of_dma_get_arwrapper_address - Get the DMA WAPPER AW address |
| * @np: device node of DMA controller |
| * @num: DMA channel thread number |
| * |
| * Return the virtual address. |
| */ |
| void __iomem *of_dma_get_awwrapper_address(struct device_node *np, unsigned int num) |
| { |
| const __be32 *reg_list; |
| unsigned int length, count; |
| |
| reg_list = of_get_property(np, "dma-awwrapper", &length); |
| count = (unsigned int)(length / sizeof(unsigned int)); |
| |
| if (!reg_list || num >= count) |
| return NULL; |
| |
| return ioremap(be32_to_cpup(reg_list + num), SZ_32); |
| } |
| EXPORT_SYMBOL_GPL(of_dma_get_awwrapper_address); |
| |
| /** |
| * of_dma_get_arwrapper_address - Get the DMA WAPPER AR address of DMA instruction |
| * @np: device node of DMA controller |
| * |
| * Return the virtual address. |
| */ |
| void __iomem *of_dma_get_instwrapper_address(struct device_node *np) |
| { |
| const __be32 *reg_list; |
| int ret = 0; |
| |
| reg_list = of_get_property(np, "dma-instwrapper", NULL); |
| |
| if (!reg_list) |
| return NULL; |
| |
| ret = be32_to_cpup(reg_list); |
| if (!ret) |
| return NULL; |
| |
| return ioremap(ret, SZ_32); |
| } |
| EXPORT_SYMBOL_GPL(of_dma_get_instwrapper_address); |
| |
| /** |
| * of_dma_get_arwrapper_address - Get the DMA WAPPER availableilable |
| * @np: device node of DMA controller |
| * |
| */ |
| bool of_dma_get_wrapper_available(struct device_node *np) |
| { |
| const __be32 *reg_list; |
| int ret = 0; |
| |
| reg_list = of_get_property(np, "dma-instwrapper", NULL); |
| |
| if (!reg_list) |
| return false; |
| |
| ret = be32_to_cpup(reg_list); |
| if (ret) |
| return true; |
| else |
| return false; |
| } |
| EXPORT_SYMBOL_GPL(of_dma_get_wrapper_available); |
| |
| /** |
| * of_dma_get_arwrapper_address - Get the DMA WAPPER availableilable |
| * @np: device node of DMA controller |
| * |
| */ |
| u64 of_dma_get_mask(struct device_node *np, char *name) |
| { |
| int bit_cnt = 0; |
| |
| of_property_read_u32(np, name, &bit_cnt); |
| |
| if (bit_cnt) |
| return ((u64)1 << bit_cnt) - 1; |
| else |
| return -1; |
| } |
| EXPORT_SYMBOL_GPL(of_dma_get_mask); |
| |
| /** |
| * of_dma_request_slave_channel - Get the DMA slave channel |
| * @np: device node to get DMA request from |
| * @name: name of desired channel |
| * |
| * Returns pointer to appropriate DMA channel on success or an error pointer. |
| */ |
| struct dma_chan *of_dma_request_slave_channel(struct device_node *np, |
| const char *name) |
| { |
| struct of_phandle_args dma_spec; |
| struct of_dma *ofdma; |
| struct dma_chan *chan; |
| int count, i; |
| int ret_no_channel = -ENODEV; |
| |
| if (!np || !name) { |
| pr_err("%s: not enough information provided\n", __func__); |
| return ERR_PTR(-ENODEV); |
| } |
| |
| /* Silently fail if there is not even the "dmas" property */ |
| if (!of_find_property(np, "dmas", NULL)) |
| return ERR_PTR(-ENODEV); |
| |
| count = of_property_count_strings(np, "dma-names"); |
| if (count < 0) { |
| pr_err("%s: dma-names property of node '%s' missing or empty\n", |
| __func__, np->full_name); |
| return ERR_PTR(-ENODEV); |
| } |
| |
| for (i = 0; i < count; i++) { |
| if (of_dma_match_channel(np, name, i, &dma_spec)) |
| continue; |
| |
| mutex_lock(&of_dma_lock); |
| ofdma = of_dma_find_controller(&dma_spec); |
| |
| if (ofdma) { |
| chan = ofdma->of_dma_xlate(&dma_spec, ofdma); |
| } else { |
| ret_no_channel = -EPROBE_DEFER; |
| chan = NULL; |
| } |
| |
| mutex_unlock(&of_dma_lock); |
| |
| of_node_put(dma_spec.np); |
| |
| if (chan) |
| return chan; |
| } |
| |
| return ERR_PTR(ret_no_channel); |
| } |
| EXPORT_SYMBOL_GPL(of_dma_request_slave_channel); |
| |
| /** |
| * of_dma_simple_xlate - Simple DMA engine translation function |
| * @dma_spec: pointer to DMA specifier as found in the device tree |
| * @of_dma: pointer to DMA controller data |
| * |
| * A simple translation function for devices that use a 32-bit value for the |
| * filter_param when calling the DMA engine dma_request_channel() function. |
| * Note that this translation function requires that #dma-cells is equal to 1 |
| * and the argument of the dma specifier is the 32-bit filter_param. Returns |
| * pointer to appropriate dma channel on success or NULL on error. |
| */ |
| struct dma_chan *of_dma_simple_xlate(struct of_phandle_args *dma_spec, |
| struct of_dma *ofdma) |
| { |
| int count = dma_spec->args_count; |
| struct of_dma_filter_info *info = ofdma->of_dma_data; |
| |
| if (!info || !info->filter_fn) |
| return NULL; |
| |
| if (count != 1) |
| return NULL; |
| |
| return dma_request_channel(info->dma_cap, info->filter_fn, |
| &dma_spec->args[0]); |
| } |
| EXPORT_SYMBOL_GPL(of_dma_simple_xlate); |
| |
| /** |
| * of_dma_xlate_by_chan_id - Translate dt property to DMA channel by channel id |
| * @dma_spec: pointer to DMA specifier as found in the device tree |
| * @of_dma: pointer to DMA controller data |
| * |
| * This function can be used as the of xlate callback for DMA driver which wants |
| * to match the channel based on the channel id. When using this xlate function |
| * the #dma-cells propety of the DMA controller dt node needs to be set to 1. |
| * The data parameter of of_dma_controller_register must be a pointer to the |
| * dma_device struct the function should match upon. |
| * |
| * Returns pointer to appropriate dma channel on success or NULL on error. |
| */ |
| struct dma_chan *of_dma_xlate_by_chan_id(struct of_phandle_args *dma_spec, |
| struct of_dma *ofdma) |
| { |
| struct dma_device *dev = ofdma->of_dma_data; |
| struct dma_chan *chan, *candidate = NULL; |
| |
| if (!dev || dma_spec->args_count != 1) |
| return NULL; |
| |
| list_for_each_entry(chan, &dev->channels, device_node) |
| if (chan->chan_id == dma_spec->args[0]) { |
| candidate = chan; |
| break; |
| } |
| |
| if (!candidate) |
| return NULL; |
| |
| return dma_get_slave_channel(candidate); |
| } |
| EXPORT_SYMBOL_GPL(of_dma_xlate_by_chan_id); |
| |
| bool of_dma_multi_irq(struct device_node *np) |
| { |
| bool ret = 0; |
| const __be32 *prop; |
| |
| prop = of_get_property(np, "#dma-multi-irq", NULL); |
| if (prop) |
| ret = be32_to_cpup(prop); |
| |
| return ret; |
| } |
| EXPORT_SYMBOL_GPL(of_dma_multi_irq); |