| From 3eb36dc9620cca5f185ec2e9af8476526b19c249 Mon Sep 17 00:00:00 2001 |
| From: Guennadi Liakhovetski <g.liakhovetski@gmx.de> |
| Date: Tue, 18 Jun 2013 18:16:57 +0200 |
| Subject: DMA: shdma: add DT support |
| |
| This patch adds Device Tree support to the shdma driver. No special DT |
| properties are used, only standard DMA DT bindings are implemented. Since |
| shdma controllers reside on SoCs, their configuration is SoC-specific and |
| shall be passed to the driver from the SoC platform data, using the |
| auxdata procedure. |
| |
| Signed-off-by: Guennadi Liakhovetski <g.liakhovetski+renesas@gmail.com> |
| Acked-by: Arnd Bergmann <arnd@arndb.de> |
| Signed-off-by: Vinod Koul <vinod.koul@intel.com> |
| (cherry picked from commit 67eacc1583909d0588c8d5d80c16298c899a6382) |
| Signed-off-by: Simon Horman <horms+renesas@verge.net.au> |
| --- |
| Documentation/devicetree/bindings/dma/shdma.txt | 75 ++++++++++++++++++++++ |
| drivers/dma/sh/Makefile | 2 +- |
| drivers/dma/sh/shdma-base.c | 26 ++++++-- |
| drivers/dma/sh/shdma-of.c | 82 +++++++++++++++++++++++++ |
| drivers/dma/sh/shdma.c | 31 ++++++++-- |
| include/linux/shdma-base.h | 2 + |
| 6 files changed, 205 insertions(+), 13 deletions(-) |
| create mode 100644 Documentation/devicetree/bindings/dma/shdma.txt |
| create mode 100644 drivers/dma/sh/shdma-of.c |
| |
| diff --git a/Documentation/devicetree/bindings/dma/shdma.txt b/Documentation/devicetree/bindings/dma/shdma.txt |
| new file mode 100644 |
| index 000000000000..c15994aa1939 |
| --- /dev/null |
| +++ b/Documentation/devicetree/bindings/dma/shdma.txt |
| @@ -0,0 +1,75 @@ |
| +* SHDMA Device Tree bindings |
| + |
| +Sh-/r-mobile and r-car systems often have multiple identical DMA controller |
| +instances, capable of serving any of a common set of DMA slave devices, using |
| +the same configuration. To describe this topology we require all compatible |
| +SHDMA DT nodes to be placed under a DMA multiplexer node. All such compatible |
| +DMAC instances have the same number of channels and use the same DMA |
| +descriptors. Therefore respective DMA DT bindings can also all be placed in the |
| +multiplexer node. Even if there is only one such DMAC instance on a system, it |
| +still has to be placed under such a multiplexer node. |
| + |
| +* DMA multiplexer |
| + |
| +Required properties: |
| +- compatible: should be "renesas,shdma-mux" |
| +- #dma-cells: should be <1>, see "dmas" property below |
| + |
| +Optional properties (currently unused): |
| +- dma-channels: number of DMA channels |
| +- dma-requests: number of DMA request signals |
| + |
| +* DMA controller |
| + |
| +Required properties: |
| +- compatible: should be "renesas,shdma" |
| + |
| +Example: |
| + dmac: dma-mux0 { |
| + compatible = "renesas,shdma-mux"; |
| + #dma-cells = <1>; |
| + dma-channels = <6>; |
| + dma-requests = <256>; |
| + reg = <0 0>; /* Needed for AUXDATA */ |
| + #address-cells = <1>; |
| + #size-cells = <1>; |
| + ranges; |
| + |
| + dma0: shdma@fe008020 { |
| + compatible = "renesas,shdma"; |
| + reg = <0xfe008020 0x270>, |
| + <0xfe009000 0xc>; |
| + interrupt-parent = <&gic>; |
| + interrupts = <0 34 4 |
| + 0 28 4 |
| + 0 29 4 |
| + 0 30 4 |
| + 0 31 4 |
| + 0 32 4 |
| + 0 33 4>; |
| + interrupt-names = "error", |
| + "ch0", "ch1", "ch2", "ch3", |
| + "ch4", "ch5"; |
| + }; |
| + |
| + dma1: shdma@fe018020 { |
| + ... |
| + }; |
| + |
| + dma2: shdma@fe028020 { |
| + ... |
| + }; |
| + }; |
| + |
| +* DMA client |
| + |
| +Required properties: |
| +- dmas: a list of <[DMA multiplexer phandle] [MID/RID value]> pairs, |
| + where MID/RID values are fixed handles, specified in the SoC |
| + manual |
| +- dma-names: a list of DMA channel names, one per "dmas" entry |
| + |
| +Example: |
| + dmas = <&dmac 0xd1 |
| + &dmac 0xd2>; |
| + dma-names = "tx", "rx"; |
| diff --git a/drivers/dma/sh/Makefile b/drivers/dma/sh/Makefile |
| index 3524b3056035..ccf17cb5af10 100644 |
| --- a/drivers/dma/sh/Makefile |
| +++ b/drivers/dma/sh/Makefile |
| @@ -1,4 +1,4 @@ |
| -obj-$(CONFIG_SH_DMAE_BASE) += shdma-base.o |
| +obj-$(CONFIG_SH_DMAE_BASE) += shdma-base.o shdma-of.o |
| obj-$(CONFIG_SH_DMAE) += shdma.o |
| obj-$(CONFIG_SUDMAC) += sudmac.o |
| obj-$(CONFIG_RCAR_HPB_DMAE) += rcar-hpbdma.o |
| diff --git a/drivers/dma/sh/shdma-base.c b/drivers/dma/sh/shdma-base.c |
| index 4acb85a10250..28ca36121631 100644 |
| --- a/drivers/dma/sh/shdma-base.c |
| +++ b/drivers/dma/sh/shdma-base.c |
| @@ -175,7 +175,18 @@ static int shdma_setup_slave(struct shdma_chan *schan, int slave_id) |
| { |
| struct shdma_dev *sdev = to_shdma_dev(schan->dma_chan.device); |
| const struct shdma_ops *ops = sdev->ops; |
| - int ret; |
| + int ret, match; |
| + |
| + if (schan->dev->of_node) { |
| + match = schan->hw_req; |
| + ret = ops->set_slave(schan, match, true); |
| + if (ret < 0) |
| + return ret; |
| + |
| + slave_id = schan->slave_id; |
| + } else { |
| + match = slave_id; |
| + } |
| |
| if (slave_id < 0 || slave_id >= slave_num) |
| return -EINVAL; |
| @@ -183,7 +194,7 @@ static int shdma_setup_slave(struct shdma_chan *schan, int slave_id) |
| if (test_and_set_bit(slave_id, shdma_slave_used)) |
| return -EBUSY; |
| |
| - ret = ops->set_slave(schan, slave_id, false); |
| + ret = ops->set_slave(schan, match, false); |
| if (ret < 0) { |
| clear_bit(slave_id, shdma_slave_used); |
| return ret; |
| @@ -206,23 +217,26 @@ static int shdma_setup_slave(struct shdma_chan *schan, int slave_id) |
| * services would have to provide their own filters, which first would check |
| * the device driver, similar to how other DMAC drivers, e.g., sa11x0-dma.c, do |
| * this, and only then, in case of a match, call this common filter. |
| + * NOTE 2: This filter function is also used in the DT case by shdma_of_xlate(). |
| + * In that case the MID-RID value is used for slave channel filtering and is |
| + * passed to this function in the "arg" parameter. |
| */ |
| bool shdma_chan_filter(struct dma_chan *chan, void *arg) |
| { |
| struct shdma_chan *schan = to_shdma_chan(chan); |
| struct shdma_dev *sdev = to_shdma_dev(schan->dma_chan.device); |
| const struct shdma_ops *ops = sdev->ops; |
| - int slave_id = (int)arg; |
| + int match = (int)arg; |
| int ret; |
| |
| - if (slave_id < 0) |
| + if (match < 0) |
| /* No slave requested - arbitrary channel */ |
| return true; |
| |
| - if (slave_id >= slave_num) |
| + if (!schan->dev->of_node && match >= slave_num) |
| return false; |
| |
| - ret = ops->set_slave(schan, slave_id, true); |
| + ret = ops->set_slave(schan, match, true); |
| if (ret < 0) |
| return false; |
| |
| diff --git a/drivers/dma/sh/shdma-of.c b/drivers/dma/sh/shdma-of.c |
| new file mode 100644 |
| index 000000000000..11bcb05cd79c |
| --- /dev/null |
| +++ b/drivers/dma/sh/shdma-of.c |
| @@ -0,0 +1,82 @@ |
| +/* |
| + * SHDMA Device Tree glue |
| + * |
| + * Copyright (C) 2013 Renesas Electronics Inc. |
| + * Author: Guennadi Liakhovetski <g.liakhovetski@gmx.de> |
| + * |
| + * This is free software; you can redistribute it and/or modify |
| + * it under the terms of version 2 of the GNU General Public License as |
| + * published by the Free Software Foundation. |
| + */ |
| + |
| +#include <linux/dmaengine.h> |
| +#include <linux/module.h> |
| +#include <linux/of.h> |
| +#include <linux/of_dma.h> |
| +#include <linux/of_platform.h> |
| +#include <linux/platform_device.h> |
| +#include <linux/shdma-base.h> |
| + |
| +#define to_shdma_chan(c) container_of(c, struct shdma_chan, dma_chan) |
| + |
| +static struct dma_chan *shdma_of_xlate(struct of_phandle_args *dma_spec, |
| + struct of_dma *ofdma) |
| +{ |
| + u32 id = dma_spec->args[0]; |
| + dma_cap_mask_t mask; |
| + struct dma_chan *chan; |
| + |
| + if (dma_spec->args_count != 1) |
| + return NULL; |
| + |
| + dma_cap_zero(mask); |
| + /* Only slave DMA channels can be allocated via DT */ |
| + dma_cap_set(DMA_SLAVE, mask); |
| + |
| + chan = dma_request_channel(mask, shdma_chan_filter, (void *)id); |
| + if (chan) |
| + to_shdma_chan(chan)->hw_req = id; |
| + |
| + return chan; |
| +} |
| + |
| +static int shdma_of_probe(struct platform_device *pdev) |
| +{ |
| + const struct of_dev_auxdata *lookup = pdev->dev.platform_data; |
| + int ret; |
| + |
| + if (!lookup) |
| + return -EINVAL; |
| + |
| + ret = of_dma_controller_register(pdev->dev.of_node, |
| + shdma_of_xlate, pdev); |
| + if (ret < 0) |
| + return ret; |
| + |
| + ret = of_platform_populate(pdev->dev.of_node, NULL, lookup, &pdev->dev); |
| + if (ret < 0) |
| + of_dma_controller_free(pdev->dev.of_node); |
| + |
| + return ret; |
| +} |
| + |
| +static const struct of_device_id shdma_of_match[] = { |
| + { .compatible = "renesas,shdma-mux", }, |
| + { } |
| +}; |
| +MODULE_DEVICE_TABLE(of, sh_dmae_of_match); |
| + |
| +static struct platform_driver shdma_of = { |
| + .driver = { |
| + .owner = THIS_MODULE, |
| + .name = "shdma-of", |
| + .of_match_table = shdma_of_match, |
| + }, |
| + .probe = shdma_of_probe, |
| +}; |
| + |
| +module_platform_driver(shdma_of); |
| + |
| +MODULE_LICENSE("GPL v2"); |
| +MODULE_DESCRIPTION("SH-DMA driver DT glue"); |
| +MODULE_AUTHOR("Guennadi Liakhovetski <g.liakhovetski@gmx.de>"); |
| diff --git a/drivers/dma/sh/shdma.c b/drivers/dma/sh/shdma.c |
| index a5a1887c34b5..b67f45f5c271 100644 |
| --- a/drivers/dma/sh/shdma.c |
| +++ b/drivers/dma/sh/shdma.c |
| @@ -301,20 +301,32 @@ static void sh_dmae_setup_xfer(struct shdma_chan *schan, |
| } |
| } |
| |
| +/* |
| + * Find a slave channel configuration from the contoller list by either a slave |
| + * ID in the non-DT case, or by a MID/RID value in the DT case |
| + */ |
| static const struct sh_dmae_slave_config *dmae_find_slave( |
| - struct sh_dmae_chan *sh_chan, int slave_id) |
| + struct sh_dmae_chan *sh_chan, int match) |
| { |
| struct sh_dmae_device *shdev = to_sh_dev(sh_chan); |
| struct sh_dmae_pdata *pdata = shdev->pdata; |
| const struct sh_dmae_slave_config *cfg; |
| int i; |
| |
| - if (slave_id >= SH_DMA_SLAVE_NUMBER) |
| - return NULL; |
| + if (!sh_chan->shdma_chan.dev->of_node) { |
| + if (match >= SH_DMA_SLAVE_NUMBER) |
| + return NULL; |
| |
| - for (i = 0, cfg = pdata->slave; i < pdata->slave_num; i++, cfg++) |
| - if (cfg->slave_id == slave_id) |
| - return cfg; |
| + for (i = 0, cfg = pdata->slave; i < pdata->slave_num; i++, cfg++) |
| + if (cfg->slave_id == match) |
| + return cfg; |
| + } else { |
| + for (i = 0, cfg = pdata->slave; i < pdata->slave_num; i++, cfg++) |
| + if (cfg->mid_rid == match) { |
| + sh_chan->shdma_chan.slave_id = cfg->slave_id; |
| + return cfg; |
| + } |
| + } |
| |
| return NULL; |
| } |
| @@ -920,11 +932,18 @@ static int sh_dmae_remove(struct platform_device *pdev) |
| return 0; |
| } |
| |
| +static const struct of_device_id sh_dmae_of_match[] = { |
| + { .compatible = "renesas,shdma", }, |
| + { } |
| +}; |
| +MODULE_DEVICE_TABLE(of, sh_dmae_of_match); |
| + |
| static struct platform_driver sh_dmae_driver = { |
| .driver = { |
| .owner = THIS_MODULE, |
| .pm = &sh_dmae_pm, |
| .name = SH_DMAE_DRV_NAME, |
| + .of_match_table = sh_dmae_of_match, |
| }, |
| .remove = sh_dmae_remove, |
| .shutdown = sh_dmae_shutdown, |
| diff --git a/include/linux/shdma-base.h b/include/linux/shdma-base.h |
| index e212720567b3..5b1c9848124c 100644 |
| --- a/include/linux/shdma-base.h |
| +++ b/include/linux/shdma-base.h |
| @@ -68,6 +68,8 @@ struct shdma_chan { |
| int id; /* Raw id of this channel */ |
| int irq; /* Channel IRQ */ |
| int slave_id; /* Client ID for slave DMA */ |
| + int hw_req; /* DMA request line for slave DMA - same |
| + * as MID/RID, used with DT */ |
| enum shdma_pm_state pm_state; |
| }; |
| |
| -- |
| 1.8.5.rc3 |
| |