Hi, On Wed, Apr 08, 2015 at 04:14:47PM +0300, Peter Ujfalusi wrote: > 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 <peter.ujfalusi@xxxxxx> > --- > drivers/dma/Kconfig | 4 + > drivers/dma/Makefile | 1 + > drivers/dma/ti-dma-crossbar.c | 185 ++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 190 insertions(+) > create mode 100644 drivers/dma/ti-dma-crossbar.c > > diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig > index 91eced044321..33a7401597be 100644 > --- a/drivers/dma/Kconfig > +++ b/drivers/dma/Kconfig > @@ -234,6 +234,9 @@ 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 > > @@ -319,6 +322,7 @@ 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 7e8301cb489d..19ac70b8af0a 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..5cb1eb7e86d2 > --- /dev/null > +++ b/drivers/dma/ti-dma-crossbar.c > @@ -0,0 +1,185 @@ > +/* > + * Copyright (C) 2015 Texas Instruments Incorporated - http://www.ti.com > + * Author: Peter Ujfalusi <peter.ujfalusi@xxxxxx> > + * > + * 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/slab.h> > +#include <linux/err.h> > +#include <linux/init.h> > +#include <linux/list.h> > +#include <linux/io.h> > +#include <linux/idr.h> > +#include <linux/of_address.h> > +#include <linux/of_device.h> > +#include <linux/of_dma.h> > + > +#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; > + > + uint safe_val; /* Value to rest the crossbar lines */ > + uint xbar_requests; /* number of DMA requests connected to XBAR */ > + uint dma_requests; /* number of DMA requests forwarded to DMA */ > +}; > + > +struct ti_dma_xbar_map { > + int xbar_in; > + int xbar_out; > +}; > + > +static inline void ti_dma_xbar_write(void __iomem *iomem, int xbar, int val) > +{ > + writew_relaxed(val, iomem + (xbar * 2)); Silently casting val (an integer) to a u16 isn't really nice I guess. At least you could be upfront about it in the prototype. > +} > + > +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%d (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 NULL; > + } > + > + 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 NULL; > + } > + > + map = kzalloc(sizeof(*map), GFP_KERNEL); > + if (!map) > + return NULL; You're leaking dma_spec->np. > + > + map->xbar_out = idr_alloc(&map_idr, NULL, 0, xbar->dma_requests, > + GFP_KERNEL); > + map->xbar_in = 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%d 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; > + void __iomem *iomem; > + int i, ret; > + > + if (!node) > + return -ENODEV; > + > + 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; > + } > + > + xbar = devm_kzalloc(&pdev->dev, sizeof(*xbar), GFP_KERNEL); > + if (!xbar) > + return -ENOMEM; And here too. > + 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", &xbar->safe_val)) > + xbar->safe_val = 0; > + > + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > + if (!res) > + return -ENODEV; > + > + if (!devm_request_mem_region(&pdev->dev, res->start, resource_size(res), > + dev_name(&pdev->dev))) > + return -ENODEV; > + > + iomem = devm_ioremap(&pdev->dev, res->start, resource_size(res)); > + if (!iomem) > + return -ENOMEM; You can use devm_ioremap_resource here. > + xbar->iomem = iomem; > + > + xbar->dmarouter.dev = &pdev->dev; > + xbar->dmarouter.route_free = ti_dma_xbar_free; > + > + platform_set_drvdata(pdev, xbar); > + > + ret = of_dma_router_register(node, ti_dma_xbar_route_allocate, > + &xbar->dmarouter); > + if (ret) > + return -ENODEV; Starting here, I'd expect that your driver can be used.... > + > + /* Reset the crossbar */ > + for (i = 0; i < xbar->dma_requests; i++) > + ti_dma_xbar_write(xbar->iomem, i, xbar->safe_val); ... however, the hardware doesn't seem ready. Isn't it a race? > + return 0; > +} > + > +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); Thanks, Maxime -- Maxime Ripard, Free Electrons Embedded Linux, Kernel and Android engineering http://free-electrons.com
Attachment:
signature.asc
Description: Digital signature
