Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754505AbbDHPZM (ORCPT ); Wed, 8 Apr 2015 11:25:12 -0400 Received: from down.free-electrons.com ([37.187.137.238]:51794 "EHLO mail.free-electrons.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754250AbbDHPZF (ORCPT ); Wed, 8 Apr 2015 11:25:05 -0400 Date: Wed, 8 Apr 2015 17:23:49 +0200 From: Maxime Ripard To: Peter Ujfalusi Cc: vinod.koul@intel.com, tony@atomide.com, linux@arm.linux.org.uk, grant.likely@linaro.org, dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org, robh+dt@kernel.org, nm@ti.com, arnd@arndb.de Subject: Re: [PATCH v4 3/8] dmaengine: Add driver for TI DMA crossbar on DRA7x Message-ID: <20150408152349.GD26727@lukather> References: <1428498892-28471-1-git-send-email-peter.ujfalusi@ti.com> <1428498892-28471-4-git-send-email-peter.ujfalusi@ti.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="iVCmgExH7+hIHJ1A" Content-Disposition: inline In-Reply-To: <1428498892-28471-4-git-send-email-peter.ujfalusi@ti.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 9096 Lines: 304 --iVCmgExH7+hIHJ1A Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable 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 c= an > be configured to route selected incoming DMA requests to specific sDMA > request. >=20 > Signed-off-by: Peter Ujfalusi > --- > 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 >=20 > 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. > =20 > +config TI_DMA_CROSSBAR > + bool > + > config ARCH_HAS_ASYNC_TX_FIND_CHANNEL > bool > =20 > @@ -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 > =20 > 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-$(CONFIG_EP93XX_DMA) +=3D ep93xx_dma.o > obj-$(CONFIG_DMA_SA11X0) +=3D sa11x0-dma.o > obj-$(CONFIG_MMP_TDMA) +=3D mmp_tdma.o > obj-$(CONFIG_DMA_OMAP) +=3D omap-dma.o > +obj-$(CONFIG_TI_DMA_CROSSBAR) +=3D ti-dma-crossbar.o > obj-$(CONFIG_DMA_BCM2835) +=3D bcm2835-dma.o > obj-$(CONFIG_MMP_PDMA) +=3D mmp_pdma.o > obj-$(CONFIG_DMA_JZ4740) +=3D 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 > + * > + * 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; > + > + 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 =3D dev_get_drvdata(dev); > + struct ti_dma_xbar_map *map =3D 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 =3D of_find_device_by_node(ofdma->of_node); > + struct ti_dma_xbar_data *xbar =3D platform_get_drvdata(pdev); > + struct ti_dma_xbar_map *map; > + > + if (dma_spec->args[0] >=3D xbar->xbar_requests) { > + dev_err(&pdev->dev, "Invalid XBAR request number: %d\n", > + dma_spec->args[0]); > + return NULL; > + } > + > + dma_spec->np =3D 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 =3D kzalloc(sizeof(*map), GFP_KERNEL); > + if (!map) > + return NULL; You're leaking dma_spec->np. > + > + map->xbar_out =3D idr_alloc(&map_idr, NULL, 0, xbar->dma_requests, > + GFP_KERNEL); > + map->xbar_in =3D dma_spec->args[0]; > + > + /* The DMA request is 1 based in sDMA */ > + dma_spec->args[0] =3D 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 =3D 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 =3D of_parse_phandle(node, "dma-masters", 0); > + if (!dma_node) { > + dev_err(&pdev->dev, "Can't get DMA master node\n"); > + return -ENODEV; > + } > + > + xbar =3D 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 =3D 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 =3D TI_XBAR_INPUTS; > + } > + > + if (of_property_read_u32(node, "ti,dma-safe-map", &xbar->safe_val)) > + xbar->safe_val =3D 0; > + > + res =3D 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 =3D devm_ioremap(&pdev->dev, res->start, resource_size(res)); > + if (!iomem) > + return -ENOMEM; You can use devm_ioremap_resource here. > + xbar->iomem =3D iomem; > + > + xbar->dmarouter.dev =3D &pdev->dev; > + xbar->dmarouter.route_free =3D ti_dma_xbar_free; > + > + platform_set_drvdata(pdev, xbar); > + > + ret =3D 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 =3D 0; i < xbar->dma_requests; i++) > + ti_dma_xbar_write(xbar->iomem, i, xbar->safe_val); =2E.. however, the hardware doesn't seem ready. Isn't it a race? > + return 0; > +} > + > +static const struct of_device_id ti_dma_xbar_match[] =3D { > + { .compatible =3D "ti,dra7-dma-crossbar" }, > + {}, > +}; > + > +static struct platform_driver ti_dma_xbar_driver =3D { > + .driver =3D { > + .name =3D "ti-dma-crossbar", > + .of_match_table =3D of_match_ptr(ti_dma_xbar_match), > + }, > + .probe =3D ti_dma_xbar_probe, > +}; > + > +int omap_dmaxbar_init(void) > +{ > + return platform_driver_register(&ti_dma_xbar_driver); > +} > +arch_initcall(omap_dmaxbar_init); Thanks, Maxime --=20 Maxime Ripard, Free Electrons Embedded Linux, Kernel and Android engineering http://free-electrons.com --iVCmgExH7+hIHJ1A Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAEBAgAGBQJVJUgFAAoJEBx+YmzsjxAg+z0P/itU07/W23Ad4LdqSi482rOj rUR5Nm/ui0rK+aJcRLL/nskybcD+XdpNskX1wsWeqgAge66nQllMQrN8DlCDfGLx 9DXbbEYsbJlzvXFPqgz0H5IiFLkinvTguXO4ptTMR5Z83e/Vc8aczSawpNPlXSgS 82HEINAhNxZujydU8OTBqnVp6E020aE/TKKnkOoGoULOe8YdLZdoJOZOa9UZK5/2 JjLFQyCtUx33tSTCxZi6NoZTUpmLwZKSDirn9opNeFuGfisw5dGsJGHD96olLhvr 15DUSHJKWFpCjlnErhnJSCQ74Q7lXYvKiX35gC2vf4OTNOmZBrYX0OOLC8WbI1tl twOkVWG49nWhQl4uX3P/fDxkNnoROyJ+O8lbEff3soJ8NuSrKlRUqm5TPDPmzlRn +ustTfy1FH12q52/9jN3zF0v5XGSl5u/FbqKBJ6SCOOviz3wTM2ncWaGeBCq9fAZ Nyuxgy73ftcJUpw/5/PvzWmd3Tnx4i106Lcjwm6EJbn/ofqYHWFkjqnryviVAiYz VGtd1wcrYfRvrKgaD8nPWeQLrr6jE2Kj3SzSbJegtn6myvX4XkQX6OMta/iGos2f 5rpydU/hyalcGN5n3ldN/mjFnu6JcWL9dcrcHMMLeAjr87XOJrFjgGVhL18Bafii i6d25NUx1s/V/XwZMR4L =ba92 -----END PGP SIGNATURE----- --iVCmgExH7+hIHJ1A-- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/