From 56f13c0d9524c5816f5dc9c91b9d766d6b1064ca Mon Sep 17 00:00:00 2001 From: Peter Ujfalusi Date: Thu, 9 Apr 2015 12:35:47 +0300 Subject: [PATCH 1/7] dmaengine: of_dma: Support for DMA routers DMA routers are transparent devices used to mux DMA requests from peripherals to DMA controllers. They are used when the SoC integrates more devices with DMA requests then their controller can handle. DRA7x is one example of such SoC, where the sDMA can hanlde 128 DMA request lines, but in SoC level it has 205 DMA requests. The of_dma_router will be registered as of_dma_controller with special xlate function and additional parameters. The driver for the router is responsible to craft the dma_spec (in the of_dma_route_allocate callback) which can be used to requests a DMA channel from the real DMA controller. This way the router can be transparent for the system while remaining generic enough to be used in different environments. Signed-off-by: Peter Ujfalusi Signed-off-by: Vinod Koul --- Documentation/devicetree/bindings/dma/dma.txt | 28 ++++++ drivers/dma/dmaengine.c | 7 ++ drivers/dma/of-dma.c | 89 +++++++++++++++++++ include/linux/dmaengine.h | 17 ++++ include/linux/of_dma.h | 21 +++++ 5 files changed, 162 insertions(+) diff --git a/Documentation/devicetree/bindings/dma/dma.txt b/Documentation/devicetree/bindings/dma/dma.txt index 82104271e754..6312fb00ce8d 100644 --- a/Documentation/devicetree/bindings/dma/dma.txt +++ b/Documentation/devicetree/bindings/dma/dma.txt @@ -31,6 +31,34 @@ Example: dma-requests = <127>; }; +* DMA router + +DMA routers are transparent IP blocks used to route DMA request lines from +devices to the DMA controller. Some SoCs (like TI DRA7x) have more peripherals +integrated with DMA requests than what the DMA controller can handle directly. + +Required property: +- dma-masters: phandle of the DMA controller or list of phandles for + the DMA controllers the router can direct the signal to. +- #dma-cells: Must be at least 1. Used to provide DMA router specific + information. See DMA client binding below for more + details. + +Optional properties: +- dma-requests: Number of incoming request lines the router can handle. +- In the node pointed by the dma-masters: + - dma-requests: The router driver might need to look for this in order + to configure the routing. + +Example: + sdma_xbar: dma-router@4a002b78 { + compatible = "ti,dra7-dma-crossbar"; + reg = <0x4a002b78 0xfc>; + #dma-cells = <1>; + dma-requests = <205>; + ti,dma-safe-map = <0>; + dma-masters = <&sdma>; + }; * DMA client diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c index 0e035a8cf401..9e5949696b1b 100644 --- a/drivers/dma/dmaengine.c +++ b/drivers/dma/dmaengine.c @@ -267,6 +267,13 @@ static void dma_chan_put(struct dma_chan *chan) /* This channel is not in use anymore, free it */ if (!chan->client_count && chan->device->device_free_chan_resources) chan->device->device_free_chan_resources(chan); + + /* If the channel is used via a DMA request router, free the mapping */ + if (chan->router && chan->router->route_free) { + chan->router->route_free(chan->router->dev, chan->route_data); + chan->router = NULL; + chan->route_data = NULL; + } } enum dma_status dma_sync_wait(struct dma_chan *chan, dma_cookie_t cookie) diff --git a/drivers/dma/of-dma.c b/drivers/dma/of-dma.c index cbd4a8aff120..1e1f2986eba8 100644 --- a/drivers/dma/of-dma.c +++ b/drivers/dma/of-dma.c @@ -44,6 +44,50 @@ static struct of_dma *of_dma_find_controller(struct of_phandle_args *dma_spec) 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 @@ -109,6 +153,51 @@ void of_dma_controller_free(struct device_node *np) } 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 diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h index ad419757241f..abf63ceabef9 100644 --- a/include/linux/dmaengine.h +++ b/include/linux/dmaengine.h @@ -221,6 +221,16 @@ struct dma_chan_percpu { unsigned long bytes_transferred; }; +/** + * struct dma_router - DMA router structure + * @dev: pointer to the DMA router device + * @route_free: function to be called when the route can be disconnected + */ +struct dma_router { + struct device *dev; + void (*route_free)(struct device *dev, void *route_data); +}; + /** * struct dma_chan - devices supply DMA channels, clients use them * @device: ptr to the dma device who supplies this channel, always !%NULL @@ -232,6 +242,8 @@ struct dma_chan_percpu { * @local: per-cpu pointer to a struct dma_chan_percpu * @client_count: how many clients are using this channel * @table_count: number of appearances in the mem-to-mem allocation table + * @router: pointer to the DMA router structure + * @route_data: channel specific data for the router * @private: private data for certain client-channel associations */ struct dma_chan { @@ -247,6 +259,11 @@ struct dma_chan { struct dma_chan_percpu __percpu *local; int client_count; int table_count; + + /* DMA router */ + struct dma_router *router; + void *route_data; + void *private; }; diff --git a/include/linux/of_dma.h b/include/linux/of_dma.h index 56bc026c143f..98ba7525929e 100644 --- a/include/linux/of_dma.h +++ b/include/linux/of_dma.h @@ -23,6 +23,9 @@ struct of_dma { struct device_node *of_node; struct dma_chan *(*of_dma_xlate) (struct of_phandle_args *, struct of_dma *); + void *(*of_dma_route_allocate) + (struct of_phandle_args *, struct of_dma *); + struct dma_router *dma_router; void *of_dma_data; }; @@ -37,12 +40,20 @@ extern int of_dma_controller_register(struct device_node *np, (struct of_phandle_args *, struct of_dma *), void *data); extern void of_dma_controller_free(struct device_node *np); + +extern 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); +#define of_dma_router_free of_dma_controller_free + extern struct dma_chan *of_dma_request_slave_channel(struct device_node *np, const char *name); extern struct dma_chan *of_dma_simple_xlate(struct of_phandle_args *dma_spec, struct of_dma *ofdma); extern struct dma_chan *of_dma_xlate_by_chan_id(struct of_phandle_args *dma_spec, struct of_dma *ofdma); + #else static inline int of_dma_controller_register(struct device_node *np, struct dma_chan *(*of_dma_xlate) @@ -56,6 +67,16 @@ static inline void of_dma_controller_free(struct device_node *np) { } +static inline 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) +{ + return -ENODEV; +} + +#define of_dma_router_free of_dma_controller_free + static inline struct dma_chan *of_dma_request_slave_channel(struct device_node *np, const char *name) { From 73f67d35b5b96eaf6c5d90fc10527c15b135eda2 Mon Sep 17 00:00:00 2001 From: Peter Ujfalusi Date: Thu, 9 Apr 2015 12:35:48 +0300 Subject: [PATCH 2/7] Documentation: devicetree: dma: Binding documentation for TI DMA crossbar The DRA7x has more peripherals with DMA requests than the sDMA can handle: 205 vs 127. All DMA requests are routed through the DMA crossbar, which can be configured to route selected incoming DMA requests to specific request line of the DMA controller. Signed-off-by: Peter Ujfalusi Signed-off-by: Vinod Koul --- .../bindings/dma/ti-dma-crossbar.txt | 52 +++++++++++++++++++ 1 file changed, 52 insertions(+) create mode 100644 Documentation/devicetree/bindings/dma/ti-dma-crossbar.txt diff --git a/Documentation/devicetree/bindings/dma/ti-dma-crossbar.txt b/Documentation/devicetree/bindings/dma/ti-dma-crossbar.txt new file mode 100644 index 000000000000..63a48928f3a8 --- /dev/null +++ b/Documentation/devicetree/bindings/dma/ti-dma-crossbar.txt @@ -0,0 +1,52 @@ +Texas Instruments DMA Crossbar (DMA request router) + +Required properties: +- compatible: "ti,dra7-dma-crossbar" for DRA7xx DMA crossbar +- reg: Memory map for accessing module +- #dma-cells: Should be set to <1>. + Clients should use the crossbar request number (input) +- dma-requests: Number of DMA requests the crossbar can receive +- dma-masters: phandle pointing to the DMA controller + +The DMA controller node need to have the following poroperties: +- dma-requests: Number of DMA requests the controller can handle + +Optional properties: +- ti,dma-safe-map: Safe routing value for unused request lines + +Example: + +/* DMA controller */ +sdma: dma-controller@4a056000 { + compatible = "ti,omap4430-sdma"; + reg = <0x4a056000 0x1000>; + interrupts = , + , + , + ; + #dma-cells = <1>; + dma-channels = <32>; + dma-requests = <127>; +}; + +/* DMA crossbar */ +sdma_xbar: dma-router@4a002b78 { + compatible = "ti,dra7-dma-crossbar"; + reg = <0x4a002b78 0xfc>; + #dma-cells = <1>; + dma-requests = <205>; + ti,dma-safe-map = <0>; + dma-masters = <&sdma>; +}; + +/* DMA client */ +uart1: serial@4806a000 { + compatible = "ti,omap4-uart"; + reg = <0x4806a000 0x100>; + interrupts-extended = <&gic GIC_SPI 67 IRQ_TYPE_LEVEL_HIGH>; + ti,hwmods = "uart1"; + clock-frequency = <48000000>; + status = "disabled"; + dmas = <&sdma_xbar 49>, <&sdma_xbar 50>; + dma-names = "tx", "rx"; +}; From 341ce712868d90fd68cc4635b7c9963a026f9207 Mon Sep 17 00:00:00 2001 From: Peter Ujfalusi Date: Thu, 9 Apr 2015 12:35:50 +0300 Subject: [PATCH 3/7] dmaengine: omap-dma: Use defines for dma channels and request count Instead of magic numbers in the code, use define for number of logical DMA channels and DMA requests. Signed-off-by: Peter Ujfalusi Signed-off-by: Vinod Koul --- drivers/dma/omap-dma.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/dma/omap-dma.c b/drivers/dma/omap-dma.c index 167dbaf65742..4065963fbffb 100644 --- a/drivers/dma/omap-dma.c +++ b/drivers/dma/omap-dma.c @@ -22,6 +22,9 @@ #include "virt-dma.h" +#define OMAP_SDMA_REQUESTS 127 +#define OMAP_SDMA_CHANNELS 32 + struct omap_dmadev { struct dma_device ddev; spinlock_t lock; @@ -33,7 +36,7 @@ struct omap_dmadev { bool legacy; spinlock_t irq_lock; uint32_t irq_enable_mask; - struct omap_chan *lch_map[32]; + struct omap_chan *lch_map[OMAP_SDMA_CHANNELS]; }; struct omap_chan { @@ -1116,7 +1119,7 @@ static int omap_dma_probe(struct platform_device *pdev) tasklet_init(&od->task, omap_dma_sched, (unsigned long)od); - for (i = 0; i < 127; i++) { + for (i = 0; i < OMAP_SDMA_REQUESTS; i++) { rc = omap_dma_chan_init(od, i); if (rc) { omap_dma_free(od); From de506089e78bc7cea77c64a836f6cfc7fa592219 Mon Sep 17 00:00:00 2001 From: Peter Ujfalusi Date: Thu, 9 Apr 2015 12:35:51 +0300 Subject: [PATCH 4/7] dmaengine: omap-dma: Take DMA request number from DT if it is available Use the dma-requests property from DT to get the number of DMA requests. In case of legacy boot or failure to find the property, use the default 127 as number of requests. Signed-off-by: Peter Ujfalusi Signed-off-by: Vinod Koul --- drivers/dma/omap-dma.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/drivers/dma/omap-dma.c b/drivers/dma/omap-dma.c index 4065963fbffb..211c9c1edf08 100644 --- a/drivers/dma/omap-dma.c +++ b/drivers/dma/omap-dma.c @@ -34,6 +34,7 @@ struct omap_dmadev { const struct omap_dma_reg *reg_map; struct omap_system_dma_plat_info *plat; bool legacy; + unsigned dma_requests; spinlock_t irq_lock; uint32_t irq_enable_mask; struct omap_chan *lch_map[OMAP_SDMA_CHANNELS]; @@ -1119,7 +1120,16 @@ static int omap_dma_probe(struct platform_device *pdev) tasklet_init(&od->task, omap_dma_sched, (unsigned long)od); - for (i = 0; i < OMAP_SDMA_REQUESTS; i++) { + od->dma_requests = OMAP_SDMA_REQUESTS; + if (pdev->dev.of_node && of_property_read_u32(pdev->dev.of_node, + "dma-requests", + &od->dma_requests)) { + dev_info(&pdev->dev, + "Missing dma-requests property, using %u.\n", + OMAP_SDMA_REQUESTS); + } + + for (i = 0; i < od->dma_requests; i++) { rc = omap_dma_chan_init(od, i); if (rc) { omap_dma_free(od); From eea531ea4147f60708c7ee9e53b5735ec387adb6 Mon Sep 17 00:00:00 2001 From: Peter Ujfalusi Date: Thu, 9 Apr 2015 12:35:52 +0300 Subject: [PATCH 5/7] dmaengine: omap-dma: Remove mapping between virtual channels and requests Do not direct map the virtual channels to sDMA request number. When the sDMA is behind of a crossbar this direct mapping can cause situations when certain channel can not be requested since the crossbar request number will no longer match with the sDMA request line. The direct mapping for virtual channels with HW request lines will make it harder to implement MEM_TO_MEM mode for the driver. Signed-off-by: Peter Ujfalusi Signed-off-by: Vinod Koul --- drivers/dma/omap-dma.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/drivers/dma/omap-dma.c b/drivers/dma/omap-dma.c index 211c9c1edf08..b19b9ee8f1d1 100644 --- a/drivers/dma/omap-dma.c +++ b/drivers/dma/omap-dma.c @@ -593,6 +593,7 @@ static void omap_dma_free_chan_resources(struct dma_chan *chan) omap_free_dma(c->dma_ch); dev_dbg(od->ddev.dev, "freeing channel for %u\n", c->dma_sig); + c->dma_sig = 0; } static size_t omap_dma_sg_size(struct omap_sg *sg) @@ -1041,7 +1042,7 @@ static int omap_dma_resume(struct dma_chan *chan) return 0; } -static int omap_dma_chan_init(struct omap_dmadev *od, int dma_sig) +static int omap_dma_chan_init(struct omap_dmadev *od) { struct omap_chan *c; @@ -1050,7 +1051,6 @@ static int omap_dma_chan_init(struct omap_dmadev *od, int dma_sig) return -ENOMEM; c->reg_map = od->reg_map; - c->dma_sig = dma_sig; c->vc.desc_free = omap_dma_desc_free; vchan_init(&c->vc, &od->ddev); INIT_LIST_HEAD(&c->node); @@ -1130,7 +1130,7 @@ static int omap_dma_probe(struct platform_device *pdev) } for (i = 0; i < od->dma_requests; i++) { - rc = omap_dma_chan_init(od, i); + rc = omap_dma_chan_init(od); if (rc) { omap_dma_free(od); return rc; @@ -1221,10 +1221,14 @@ static struct platform_driver omap_dma_driver = { bool omap_dma_filter_fn(struct dma_chan *chan, void *param) { if (chan->device->dev->driver == &omap_dma_driver.driver) { + struct omap_dmadev *od = to_omap_dma_dev(chan->device); struct omap_chan *c = to_omap_dma_chan(chan); unsigned req = *(unsigned *)param; - return req == c->dma_sig; + if (req <= od->dma_requests) { + c->dma_sig = req; + return true; + } } return false; } From 8a32222693af0edf4ad0ed2c6c4c9e383fd922dd Mon Sep 17 00:00:00 2001 From: Peter Ujfalusi Date: Thu, 9 Apr 2015 12:35:53 +0300 Subject: [PATCH 6/7] dmaengine: omap-dma: Reduce the number of virtual channels Since the mapping between the hardware request lines and channels has been removed it no longer make sense to have too many channels. Set the number of channels to match with the number of logical channels supported by sDMA. Signed-off-by: Peter Ujfalusi Signed-off-by: Vinod Koul --- drivers/dma/omap-dma.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/dma/omap-dma.c b/drivers/dma/omap-dma.c index b19b9ee8f1d1..7f154c138200 100644 --- a/drivers/dma/omap-dma.c +++ b/drivers/dma/omap-dma.c @@ -1129,7 +1129,7 @@ static int omap_dma_probe(struct platform_device *pdev) OMAP_SDMA_REQUESTS); } - for (i = 0; i < od->dma_requests; i++) { + for (i = 0; i < OMAP_SDMA_CHANNELS; i++) { rc = omap_dma_chan_init(od); if (rc) { omap_dma_free(od); From a074ae38f859b90bd259f5df43784834b44412d1 Mon Sep 17 00:00:00 2001 From: Peter Ujfalusi Date: Thu, 9 Apr 2015 12:35:49 +0300 Subject: [PATCH 7/7] dmaengine: Add driver for TI DMA crossbar on DRA7x The DRA7x has more peripherals with DMA requests than the sDMA can handle: 205 vs 127. All DMA requests are routed through the DMA crossbar, which can be configured to route selected incoming DMA requests to specific sDMA request. Signed-off-by: Peter Ujfalusi Signed-off-by: Vinod Koul --- drivers/dma/Kconfig | 4 + drivers/dma/Makefile | 1 + drivers/dma/ti-dma-crossbar.c | 188 ++++++++++++++++++++++++++++++++++ 3 files changed, 193 insertions(+) create mode 100644 drivers/dma/ti-dma-crossbar.c diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig index fd7ac13f2574..681651aed320 100644 --- a/drivers/dma/Kconfig +++ b/drivers/dma/Kconfig @@ -245,6 +245,9 @@ config TI_EDMA Enable support for the TI EDMA controller. This DMA engine is found on TI DaVinci and AM33xx parts. +config TI_DMA_CROSSBAR + bool + config ARCH_HAS_ASYNC_TX_FIND_CHANNEL bool @@ -330,6 +333,7 @@ config DMA_OMAP depends on ARCH_OMAP select DMA_ENGINE select DMA_VIRTUAL_CHANNELS + select TI_DMA_CROSSBAR if SOC_DRA7XX config DMA_BCM2835 tristate "BCM2835 DMA engine support" diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile index 69f77d5ba53b..535919559f12 100644 --- a/drivers/dma/Makefile +++ b/drivers/dma/Makefile @@ -38,6 +38,7 @@ obj-$(CONFIG_EP93XX_DMA) += ep93xx_dma.o obj-$(CONFIG_DMA_SA11X0) += sa11x0-dma.o obj-$(CONFIG_MMP_TDMA) += mmp_tdma.o obj-$(CONFIG_DMA_OMAP) += omap-dma.o +obj-$(CONFIG_TI_DMA_CROSSBAR) += ti-dma-crossbar.o obj-$(CONFIG_DMA_BCM2835) += bcm2835-dma.o obj-$(CONFIG_MMP_PDMA) += mmp_pdma.o obj-$(CONFIG_DMA_JZ4740) += dma-jz4740.o diff --git a/drivers/dma/ti-dma-crossbar.c b/drivers/dma/ti-dma-crossbar.c new file mode 100644 index 000000000000..24f5ca2356bf --- /dev/null +++ b/drivers/dma/ti-dma-crossbar.c @@ -0,0 +1,188 @@ +/* + * Copyright (C) 2015 Texas Instruments Incorporated - http://www.ti.com + * Author: Peter Ujfalusi + * + * 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 +#include +#include +#include +#include +#include +#include +#include +#include + +#define TI_XBAR_OUTPUTS 127 +#define TI_XBAR_INPUTS 256 + +static DEFINE_IDR(map_idr); + +struct ti_dma_xbar_data { + void __iomem *iomem; + + struct dma_router dmarouter; + + u16 safe_val; /* Value to rest the crossbar lines */ + u32 xbar_requests; /* number of DMA requests connected to XBAR */ + u32 dma_requests; /* number of DMA requests forwarded to DMA */ +}; + +struct ti_dma_xbar_map { + u16 xbar_in; + int xbar_out; +}; + +static inline void ti_dma_xbar_write(void __iomem *iomem, int xbar, u16 val) +{ + writew_relaxed(val, iomem + (xbar * 2)); +} + +static void ti_dma_xbar_free(struct device *dev, void *route_data) +{ + struct ti_dma_xbar_data *xbar = dev_get_drvdata(dev); + struct ti_dma_xbar_map *map = route_data; + + dev_dbg(dev, "Unmapping XBAR%u (was routed to %d)\n", + map->xbar_in, map->xbar_out); + + ti_dma_xbar_write(xbar->iomem, map->xbar_out, xbar->safe_val); + idr_remove(&map_idr, map->xbar_out); + kfree(map); +} + +static void *ti_dma_xbar_route_allocate(struct of_phandle_args *dma_spec, + struct of_dma *ofdma) +{ + struct platform_device *pdev = of_find_device_by_node(ofdma->of_node); + struct ti_dma_xbar_data *xbar = platform_get_drvdata(pdev); + struct ti_dma_xbar_map *map; + + if (dma_spec->args[0] >= xbar->xbar_requests) { + dev_err(&pdev->dev, "Invalid XBAR request number: %d\n", + dma_spec->args[0]); + return ERR_PTR(-EINVAL); + } + + /* The of_node_put() will be done in the core for the node */ + dma_spec->np = of_parse_phandle(ofdma->of_node, "dma-masters", 0); + if (!dma_spec->np) { + dev_err(&pdev->dev, "Can't get DMA master\n"); + return ERR_PTR(-EINVAL); + } + + map = kzalloc(sizeof(*map), GFP_KERNEL); + if (!map) { + of_node_put(dma_spec->np); + return ERR_PTR(-ENOMEM); + } + + map->xbar_out = idr_alloc(&map_idr, NULL, 0, xbar->dma_requests, + GFP_KERNEL); + map->xbar_in = (u16)dma_spec->args[0]; + + /* The DMA request is 1 based in sDMA */ + dma_spec->args[0] = map->xbar_out + 1; + + dev_dbg(&pdev->dev, "Mapping XBAR%u to DMA%d\n", + map->xbar_in, map->xbar_out); + + ti_dma_xbar_write(xbar->iomem, map->xbar_out, map->xbar_in); + + return map; +} + +static int ti_dma_xbar_probe(struct platform_device *pdev) +{ + struct device_node *node = pdev->dev.of_node; + struct device_node *dma_node; + struct ti_dma_xbar_data *xbar; + struct resource *res; + u32 safe_val; + void __iomem *iomem; + int i, ret; + + if (!node) + return -ENODEV; + + xbar = devm_kzalloc(&pdev->dev, sizeof(*xbar), GFP_KERNEL); + if (!xbar) + return -ENOMEM; + + dma_node = of_parse_phandle(node, "dma-masters", 0); + if (!dma_node) { + dev_err(&pdev->dev, "Can't get DMA master node\n"); + return -ENODEV; + } + + if (of_property_read_u32(dma_node, "dma-requests", + &xbar->dma_requests)) { + dev_info(&pdev->dev, + "Missing XBAR output information, using %u.\n", + TI_XBAR_OUTPUTS); + xbar->dma_requests = TI_XBAR_OUTPUTS; + } + of_node_put(dma_node); + + if (of_property_read_u32(node, "dma-requests", &xbar->xbar_requests)) { + dev_info(&pdev->dev, + "Missing XBAR input information, using %u.\n", + TI_XBAR_INPUTS); + xbar->xbar_requests = TI_XBAR_INPUTS; + } + + if (!of_property_read_u32(node, "ti,dma-safe-map", &safe_val)) + xbar->safe_val = (u16)safe_val; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) + return -ENODEV; + + iomem = devm_ioremap_resource(&pdev->dev, res); + if (!iomem) + return -ENOMEM; + + xbar->iomem = iomem; + + xbar->dmarouter.dev = &pdev->dev; + xbar->dmarouter.route_free = ti_dma_xbar_free; + + platform_set_drvdata(pdev, xbar); + + /* Reset the crossbar */ + for (i = 0; i < xbar->dma_requests; i++) + ti_dma_xbar_write(xbar->iomem, i, xbar->safe_val); + + ret = of_dma_router_register(node, ti_dma_xbar_route_allocate, + &xbar->dmarouter); + if (ret) { + /* Restore the defaults for the crossbar */ + for (i = 0; i < xbar->dma_requests; i++) + ti_dma_xbar_write(xbar->iomem, i, i); + } + + return ret; +} + +static const struct of_device_id ti_dma_xbar_match[] = { + { .compatible = "ti,dra7-dma-crossbar" }, + {}, +}; + +static struct platform_driver ti_dma_xbar_driver = { + .driver = { + .name = "ti-dma-crossbar", + .of_match_table = of_match_ptr(ti_dma_xbar_match), + }, + .probe = ti_dma_xbar_probe, +}; + +int omap_dmaxbar_init(void) +{ + return platform_driver_register(&ti_dma_xbar_driver); +} +arch_initcall(omap_dmaxbar_init);