Re: [PATCH v8 3/3] dmaengine: fsl-edma: add ColdFire mcf5441x edma support

[Krzysztof Kozlowski <krzk@kernel.org>]

On 3 August 2018 at 21:32, Angelo Dureghello <angelo@sysam.it> wrote:
> This patch adds support for ColdFire mcf5441x-family edma
> module.
>
> The ColdFire edma module is slightly different from fsl-edma,
> so a new driver is added. But most of the code is common
> between fsl-edma and mcf-edma so it has been collected into a
> separate common module fsl-edma-common (patch 1/3).
>
> Signed-off-by: Angelo Dureghello <angelo@sysam.it>
> ---
> Changes for v7:
> - patch rewritten from scratch, this patch (3/3) has just been added.
> ---
>  drivers/dma/Kconfig                        |  11 +
>  drivers/dma/Makefile                       |   1 +
>  drivers/dma/fsl-edma-common.c              |  24 +-
>  drivers/dma/mcf-edma.c                     | 315 +++++++++++++++++++++
>  include/linux/platform_data/dma-mcf-edma.h |  38 +++
>  5 files changed, 385 insertions(+), 4 deletions(-)
>  create mode 100644 drivers/dma/mcf-edma.c
>  create mode 100644 include/linux/platform_data/dma-mcf-edma.h
>
> diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
> index ca1680afa20a..b45008e9c7e9 100644
> --- a/drivers/dma/Kconfig
> +++ b/drivers/dma/Kconfig
> @@ -320,6 +320,17 @@ config LPC18XX_DMAMUX
>           Enable support for DMA on NXP LPC18xx/43xx platforms
>           with PL080 and multiplexed DMA request lines.
>
> +config MCF_EDMA
> +       tristate "Freescale eDMA engine support, ColdFire mcf5441x SoCs"
> +       depends on M5441x
> +       select DMA_ENGINE
> +       select DMA_VIRTUAL_CHANNELS
> +       help
> +         Support the Freescale ColdFire eDMA engine, 64-channel
> +         implementation that performs complex data transfers with
> +         minimal intervention from a host processor.
> +         This module can be found on Freescale ColdFire mcf5441x SoCs.
> +
>  config MMP_PDMA
>         bool "MMP PDMA support"
>         depends on ARCH_MMP || ARCH_PXA || COMPILE_TEST
> diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile
> index 66022f59fca4..d97f317f4b34 100644
> --- a/drivers/dma/Makefile
> +++ b/drivers/dma/Makefile
> @@ -32,6 +32,7 @@ obj-$(CONFIG_DW_DMAC_CORE) += dw/
>  obj-$(CONFIG_EP93XX_DMA) += ep93xx_dma.o
>  obj-$(CONFIG_FSL_DMA) += fsldma.o
>  obj-$(CONFIG_FSL_EDMA) += fsl-edma.o fsl-edma-common.o
> +obj-$(CONFIG_MCF_EDMA) += mcf-edma.o fsl-edma-common.o
>  obj-$(CONFIG_FSL_RAID) += fsl_raid.o
>  obj-$(CONFIG_HSU_DMA) += hsu/
>  obj-$(CONFIG_IMG_MDC_DMA) += img-mdc-dma.o
> diff --git a/drivers/dma/fsl-edma-common.c b/drivers/dma/fsl-edma-common.c
> index 948a3ee51bbb..5a830a238a0c 100644
> --- a/drivers/dma/fsl-edma-common.c
> +++ b/drivers/dma/fsl-edma-common.c
> @@ -102,8 +102,16 @@ static void fsl_edma_enable_request(struct fsl_edma_chan *fsl_chan)
>         struct edma_regs *regs = &fsl_chan->edma->regs;
>         u32 ch = fsl_chan->vchan.chan.chan_id;
>
> -       edma_writeb(fsl_chan->edma, EDMA_SEEI_SEEI(ch), regs->seei);
> -       edma_writeb(fsl_chan->edma, ch, regs->serq);
> +       if (fsl_chan->edma->version == v1) {
> +               edma_writeb(fsl_chan->edma, EDMA_SEEI_SEEI(ch), regs->seei);
> +               edma_writeb(fsl_chan->edma, ch, regs->serq);
> +       } else {
> +               /* ColdFire is big endian, and accesses natively
> +                * big endian I/O peripherals
> +                */
> +               iowrite8(EDMA_SEEI_SEEI(ch), regs->seei);
> +               iowrite8(ch, regs->serq);
> +       }
>  }
>
>  void fsl_edma_disable_request(struct fsl_edma_chan *fsl_chan)
> @@ -111,8 +119,16 @@ void fsl_edma_disable_request(struct fsl_edma_chan *fsl_chan)
>         struct edma_regs *regs = &fsl_chan->edma->regs;
>         u32 ch = fsl_chan->vchan.chan.chan_id;
>
> -       edma_writeb(fsl_chan->edma, ch, regs->cerq);
> -       edma_writeb(fsl_chan->edma, EDMA_CEEI_CEEI(ch), regs->ceei);
> +       if (fsl_chan->edma->version == v1) {
> +               edma_writeb(fsl_chan->edma, ch, regs->cerq);
> +               edma_writeb(fsl_chan->edma, EDMA_CEEI_CEEI(ch), regs->ceei);
> +       } else {
> +               /* ColdFire is big endian, and accesses natively
> +                * big endian I/O peripherals
> +                */
> +               iowrite8(ch, regs->cerq);
> +               iowrite8(EDMA_CEEI_CEEI(ch), regs->ceei);
> +       }
>  }
>  EXPORT_SYMBOL_GPL(fsl_edma_disable_request);
>
> diff --git a/drivers/dma/mcf-edma.c b/drivers/dma/mcf-edma.c
> new file mode 100644
> index 000000000000..31e5317a8f90
> --- /dev/null
> +++ b/drivers/dma/mcf-edma.c
> @@ -0,0 +1,315 @@
> +// SPDX-License-Identifier: GPL-2.0
> +//
> +// Copyright (c) 2013-2014 Freescale Semiconductor, Inc

Same comment as to 1/3 - if this is derivative work...

> +// Copyright (c) 2017 Sysam, Angelo Dureghello  <angelo@sysam.it>
> +
> +#include <linux/module.h>
> +#include <linux/interrupt.h>
> +#include <linux/dmaengine.h>
> +#include <linux/platform_device.h>
> +#include <linux/platform_data/dma-mcf-edma.h>
> +
> +#include "fsl-edma-common.h"
> +
> +#define EDMA_CHANNELS          64
> +#define EDMA_MASK_CH(x)                ((x) & GENMASK(5, 0))
> +
> +static irqreturn_t mcf_edma_tx_handler(int irq, void *dev_id)
> +{
> +       struct fsl_edma_engine *mcf_edma = dev_id;
> +       struct edma_regs *regs = &mcf_edma->regs;
> +       unsigned int ch;
> +       struct fsl_edma_chan *mcf_chan;
> +       u64 intmap;
> +
> +       intmap = ioread32(regs->inth);
> +       intmap <<= 32;
> +       intmap |= ioread32(regs->intl);
> +       if (!intmap)
> +               return IRQ_NONE;
> +
> +       for (ch = 0; ch < mcf_edma->n_chans; ch++) {
> +               if (intmap & BIT(ch)) {
> +                       iowrite8(EDMA_MASK_CH(ch), regs->cint);
> +
> +                       mcf_chan = &mcf_edma->chans[ch];
> +
> +                       spin_lock(&mcf_chan->vchan.lock);
> +                       if (!mcf_chan->edesc->iscyclic) {
> +                               list_del(&mcf_chan->edesc->vdesc.node);
> +                               vchan_cookie_complete(&mcf_chan->edesc->vdesc);
> +                               mcf_chan->edesc = NULL;
> +                               mcf_chan->status = DMA_COMPLETE;
> +                               mcf_chan->idle = true;
> +                       } else {
> +                               vchan_cyclic_callback(&mcf_chan->edesc->vdesc);
> +                       }
> +
> +                       if (!mcf_chan->edesc)
> +                               fsl_edma_xfer_desc(mcf_chan);
> +
> +                       spin_unlock(&mcf_chan->vchan.lock);
> +               }
> +       }
> +
> +       return IRQ_HANDLED;
> +}
> +
> +static irqreturn_t mcf_edma_err_handler(int irq, void *dev_id)
> +{
> +       struct fsl_edma_engine *mcf_edma = dev_id;
> +       struct edma_regs *regs = &mcf_edma->regs;
> +       unsigned int err, ch;
> +
> +       err = ioread32(regs->errl);
> +       if (!err)
> +               return IRQ_NONE;
> +
> +       for (ch = 0; ch < (EDMA_CHANNELS / 2); ch++) {
> +               if (err & BIT(ch)) {
> +                       fsl_edma_disable_request(&mcf_edma->chans[ch]);
> +                       iowrite8(EDMA_CERR_CERR(ch), regs->cerr);
> +                       mcf_edma->chans[ch].status = DMA_ERROR;
> +                       mcf_edma->chans[ch].idle = true;
> +               }
> +       }
> +
> +       err = ioread32(regs->errh);
> +       if (!err)
> +               return IRQ_NONE;
> +
> +       for (ch = (EDMA_CHANNELS / 2); ch < EDMA_CHANNELS; ch++) {
> +               if (err & (BIT(ch - (EDMA_CHANNELS / 2)))) {
> +                       fsl_edma_disable_request(&mcf_edma->chans[ch]);
> +                       iowrite8(EDMA_CERR_CERR(ch), regs->cerr);
> +                       mcf_edma->chans[ch].status = DMA_ERROR;
> +                       mcf_edma->chans[ch].idle = true;
> +               }
> +       }
> +
> +       return IRQ_HANDLED;
> +}
> +
> +static int mcf_edma_irq_init(struct platform_device *pdev,
> +                               struct fsl_edma_engine *mcf_edma)
> +{
> +       int ret = 0, i;
> +       struct resource *res;
> +
> +       res = platform_get_resource_byname(pdev,
> +                               IORESOURCE_IRQ, "edma-tx-00-15");
> +       if (!res)
> +               return -1;
> +
> +       for (ret = 0, i = res->start; i <= res->end; ++i)
> +               ret |= request_irq(i, mcf_edma_tx_handler, 0, "eDMA", mcf_edma);
> +       if (ret)
> +               return ret;
> +
> +       res = platform_get_resource_byname(pdev,
> +                       IORESOURCE_IRQ, "edma-tx-16-55");
> +       if (!res)
> +               return -1;
> +
> +       for (ret = 0, i = res->start; i <= res->end; ++i)
> +               ret |= request_irq(i, mcf_edma_tx_handler, 0, "eDMA", mcf_edma);
> +       if (ret)
> +               return ret;
> +
> +       ret = platform_get_irq_byname(pdev, "edma-tx-56-63");
> +       if (ret != -ENXIO) {
> +               ret = request_irq(ret, mcf_edma_tx_handler,
> +                                 0, "eDMA", mcf_edma);
> +               if (ret)
> +                       return ret;
> +       }
> +
> +       ret = platform_get_irq_byname(pdev, "edma-err");
> +       if (ret != -ENXIO) {
> +               ret = request_irq(ret, mcf_edma_err_handler,
> +                                 0, "eDMA", mcf_edma);
> +               if (ret)
> +                       return ret;
> +       }
> +
> +       return 0;
> +}
> +
> +static void mcf_edma_irq_free(struct platform_device *pdev,
> +                               struct fsl_edma_engine *mcf_edma)
> +{
> +       int irq;
> +       struct resource *res;
> +
> +       res = platform_get_resource_byname(pdev,
> +                       IORESOURCE_IRQ, "edma-tx-00-15");
> +       if (res) {
> +               for (irq = res->start; irq <= res->end; irq++)
> +                       free_irq(irq, mcf_edma);
> +       }
> +
> +       res = platform_get_resource_byname(pdev,
> +                       IORESOURCE_IRQ, "edma-tx-16-55");
> +       if (res) {
> +               for (irq = res->start; irq <= res->end; irq++)
> +                       free_irq(irq, mcf_edma);
> +       }
> +
> +       irq = platform_get_irq_byname(pdev, "edma-tx-56-63");
> +       if (irq != -ENXIO)
> +               free_irq(irq, mcf_edma);
> +
> +       irq = platform_get_irq_byname(pdev, "edma-err");
> +       if (irq != -ENXIO)
> +               free_irq(irq, mcf_edma);
> +}
> +
> +static int mcf_edma_probe(struct platform_device *pdev)
> +{
> +       struct mcf_edma_platform_data *pdata;
> +       struct fsl_edma_engine *mcf_edma;
> +       struct fsl_edma_chan *mcf_chan;
> +       struct edma_regs *regs;
> +       struct resource *res;
> +       int ret, i, len, chans;
> +
> +       pdata = dev_get_platdata(&pdev->dev);
> +       if (!pdata)
> +               return PTR_ERR(pdata);
> +
> +       chans = pdata->dma_channels;
> +       len = sizeof(*mcf_edma) + sizeof(*mcf_chan) * chans;
> +       mcf_edma = devm_kzalloc(&pdev->dev, len, GFP_KERNEL);
> +       if (!mcf_edma)
> +               return -ENOMEM;
> +
> +       mcf_edma->n_chans = chans;
> +
> +       /* Set up version for ColdFire edma */
> +       mcf_edma->version = v2;
> +       mcf_edma->big_endian = 1;
> +
> +       if (!mcf_edma->n_chans) {
> +               dev_info(&pdev->dev, "setting default channel number to 64");
> +               mcf_edma->n_chans = 64;
> +       }
> +
> +       mutex_init(&mcf_edma->fsl_edma_mutex);
> +
> +       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +
> +       mcf_edma->membase = devm_ioremap_resource(&pdev->dev, res);
> +       if (IS_ERR(mcf_edma->membase))
> +               return PTR_ERR(mcf_edma->membase);
> +
> +       fsl_edma_setup_regs(mcf_edma);
> +       regs = &mcf_edma->regs;
> +
> +       INIT_LIST_HEAD(&mcf_edma->dma_dev.channels);
> +       for (i = 0; i < mcf_edma->n_chans; i++) {
> +               struct fsl_edma_chan *mcf_chan = &mcf_edma->chans[i];
> +
> +               mcf_chan->edma = mcf_edma;
> +               mcf_chan->slave_id = i;
> +               mcf_chan->idle = true;
> +               mcf_chan->vchan.desc_free = fsl_edma_free_desc;
> +               vchan_init(&mcf_chan->vchan, &mcf_edma->dma_dev);
> +               iowrite32(0x0, &regs->tcd[i].csr);
> +       }
> +
> +       iowrite32(~0, regs->inth);
> +       iowrite32(~0, regs->intl);
> +
> +       ret = mcf_edma_irq_init(pdev, mcf_edma);
> +       if (ret)
> +               return ret;
> +
> +       dma_cap_set(DMA_PRIVATE, mcf_edma->dma_dev.cap_mask);
> +       dma_cap_set(DMA_SLAVE, mcf_edma->dma_dev.cap_mask);
> +       dma_cap_set(DMA_CYCLIC, mcf_edma->dma_dev.cap_mask);
> +
> +       mcf_edma->dma_dev.dev = &pdev->dev;
> +       mcf_edma->dma_dev.device_alloc_chan_resources =
> +                       fsl_edma_alloc_chan_resources;
> +       mcf_edma->dma_dev.device_free_chan_resources =
> +                       fsl_edma_free_chan_resources;
> +       mcf_edma->dma_dev.device_config = fsl_edma_slave_config;
> +       mcf_edma->dma_dev.device_prep_dma_cyclic =
> +                       fsl_edma_prep_dma_cyclic;
> +       mcf_edma->dma_dev.device_prep_slave_sg = fsl_edma_prep_slave_sg;
> +       mcf_edma->dma_dev.device_tx_status = fsl_edma_tx_status;
> +       mcf_edma->dma_dev.device_pause = fsl_edma_pause;
> +       mcf_edma->dma_dev.device_resume = fsl_edma_resume;
> +       mcf_edma->dma_dev.device_terminate_all = fsl_edma_terminate_all;
> +       mcf_edma->dma_dev.device_issue_pending = fsl_edma_issue_pending;
> +
> +       mcf_edma->dma_dev.src_addr_widths = FSL_EDMA_BUSWIDTHS;
> +       mcf_edma->dma_dev.dst_addr_widths = FSL_EDMA_BUSWIDTHS;
> +       mcf_edma->dma_dev.directions =
> +                       BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
> +
> +       mcf_edma->dma_dev.filter.fn = mcf_edma_filter_fn;
> +       mcf_edma->dma_dev.filter.map = pdata->slave_map;
> +       mcf_edma->dma_dev.filter.mapcnt = pdata->slavecnt;
> +
> +       platform_set_drvdata(pdev, mcf_edma);
> +
> +       ret = dma_async_device_register(&mcf_edma->dma_dev);
> +       if (ret) {
> +               dev_err(&pdev->dev,
> +                       "Can't register Freescale eDMA engine. (%d)\n", ret);
> +               return ret;
> +       }
> +
> +       /* Enable round robin arbitration */
> +       iowrite32(EDMA_CR_ERGA | EDMA_CR_ERCA, regs->cr);
> +
> +       return 0;
> +}
> +
> +static int mcf_edma_remove(struct platform_device *pdev)
> +{
> +       struct fsl_edma_engine *mcf_edma = platform_get_drvdata(pdev);
> +
> +       mcf_edma_irq_free(pdev, mcf_edma);
> +       fsl_edma_cleanup_vchan(&mcf_edma->dma_dev);
> +       dma_async_device_unregister(&mcf_edma->dma_dev);
> +
> +       return 0;
> +}
> +
> +static struct platform_driver mcf_edma_driver = {
> +       .driver         = {
> +               .name   = "mcf-edma",
> +       },
> +       .probe          = mcf_edma_probe,
> +       .remove         = mcf_edma_remove,
> +};
> +
> +bool mcf_edma_filter_fn(struct dma_chan *chan, void *param)
> +{
> +       if (chan->device->dev->driver == &mcf_edma_driver.driver) {
> +               struct fsl_edma_chan *mcf_chan = to_fsl_edma_chan(chan);
> +
> +               return (mcf_chan->slave_id == (int)param);
> +       }
> +
> +       return false;
> +}
> +EXPORT_SYMBOL(mcf_edma_filter_fn);
> +
> +static int __init mcf_edma_init(void)
> +{
> +       return platform_driver_register(&mcf_edma_driver);
> +}
> +subsys_initcall(mcf_edma_init);
> +
> +static void __exit mcf_edma_exit(void)
> +{
> +       platform_driver_unregister(&mcf_edma_driver);
> +}
> +module_exit(mcf_edma_exit);
> +
> +MODULE_ALIAS("platform:mcf-edma");
> +MODULE_DESCRIPTION("Freescale eDMA engine driver, ColdFire family");
> +MODULE_LICENSE("GPL v2");
> diff --git a/include/linux/platform_data/dma-mcf-edma.h b/include/linux/platform_data/dma-mcf-edma.h
> new file mode 100644
> index 000000000000..9a1819acb28f
> --- /dev/null
> +++ b/include/linux/platform_data/dma-mcf-edma.h
> @@ -0,0 +1,38 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Freescale eDMA platform data, ColdFire SoC's family.
> + *
> + * Copyright (c) 2017 Angelo Dureghello <angelo@sysam.it>
> + *
> + * 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.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + */
> +
> +#ifndef __MACH_MCF_EDMA_H__
> +#define __MACH_MCF_EDMA_H__

The guard should rather match current location, e.g.
__LINUX_PLATFORM_DATA_MCF_EDMA_H__

Tested-by: Krzysztof Kozlowski <krzk@kernel.org>

Best regards,
Krzysztof