On Wed, Mar 11, 2015 at 03:23:26PM +0200, 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 | 190 ++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 195 insertions(+) > create mode 100644 drivers/dma/ti-dma-crossbar.c > > diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig > index 074ffad334a7..519657a37ca1 100644 > --- a/drivers/dma/Kconfig > +++ b/drivers/dma/Kconfig > @@ -247,6 +247,9 @@ 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 > > @@ -332,6 +335,7 @@ 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 bf4485800c60..6ec7af6a416c 100644 > --- a/drivers/dma/Makefile > +++ b/drivers/dma/Makefile > @@ -39,6 +39,7 @@ 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..591307bd4370 > --- /dev/null > +++ b/drivers/dma/ti-dma-crossbar.c > @@ -0,0 +1,190 @@ > +/* > + * 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/regmap.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 Ideally this should be moved to DT. Will next revision of this chip always support these output and inputs? > + > +static DEFINE_IDR(map_idr); > + > +struct ti_dma_xbar_data { > + struct dma_router dmarouter; > + struct regmap *regmap; > + > + 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 */ > + > + void __iomem *iomem; > +}; > + > +struct ti_dma_xbar_map { > + int xbar_in; > + int xbar_out; > +}; > + > +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); > + > + regmap_write(xbar->regmap, map->xbar_out * 2, 0); just out of curiosity how much do you save using regmap :) > +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-device", 0); > + if (!dma_node) { > + dev_err(&pdev->dev, "Can't get target DMA node\n"); > + return -ENODEV; > + } > + > + xbar = devm_kzalloc(&pdev->dev, sizeof(*xbar), GFP_KERNEL); > + if (!xbar) > + return -ENOMEM; > + > + 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); _put here? > +int omap_dmaxbar_init(void) > +{ > + return platform_driver_register(&ti_dma_xbar_driver); > +} > +arch_initcall(omap_dmaxbar_init); why arch_initcall? -- ~Vinod -- To unsubscribe from this list: send the line "unsubscribe dmaengine" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
