linux-fpga.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Greg KH <gregkh@linuxfoundation.org>
To: Nava kishore Manne <nava.manne@xilinx.com>
Cc: robh+dt@kernel.org, michal.simek@xilinx.com, mdf@kernel.org,
	trix@redhat.com, arnd@arndb.de, rajan.vaja@xilinx.com,
	amit.sunil.dhamne@xilinx.com, tejas.patel@xilinx.com,
	zou_wei@huawei.com, lakshmi.sai.krishna.potthuri@xilinx.com,
	ravi.patel@xilinx.com, iwamatsu@nigauri.org,
	wendy.liang@xilinx.com, devicetree@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org, linux-fpga@vger.kernel.org,
	git@xilinx.com, chinnikishore369@gmail.com,
	Appana Durga Kedareswara rao <appana.durga.rao@xilinx.com>
Subject: Re: [PATCH v6 4/4] fpga: versal-fpga: Add versal fpga manager driver
Date: Thu, 20 May 2021 10:48:54 +0200	[thread overview]
Message-ID: <YKYidhc25e4SIwNi@kroah.com> (raw)
In-Reply-To: <20210520080954.1393-5-nava.manne@xilinx.com>

On Thu, May 20, 2021 at 01:39:54PM +0530, Nava kishore Manne wrote:
> Add support for Xilinx Versal FPGA manager.
> 
> PDI source type can be DDR, OCM, QSPI flash etc..
> But driver allocates memory always from DDR, Since driver supports only
> DDR source type.
> 
> Signed-off-by: Appana Durga Kedareswara rao <appana.durga.rao@xilinx.com>
> Signed-off-by: Nava kishore Manne <nava.manne@xilinx.com>
> Reviewed-by: Moritz Fischer <mdf@kernel.org>
> ---
> Changes for v2:
>                 -Updated the Fpga Mgr registrations call's
>                  to 5.11
>                 -Fixed some minor coding issues as suggested by
>                  Moritz.
> Changes for v3:
>                 -Rewritten the Versal fpga Kconfig contents.
> Changes for v4:
>                 -Rebased the changes on linux-next.
>                  No functional changes.
> Changes for v5:
>                 -None.
> Changes for v6:
>                 -None.
> 
>  drivers/fpga/Kconfig       |   9 +++
>  drivers/fpga/Makefile      |   1 +
>  drivers/fpga/versal-fpga.c | 117 +++++++++++++++++++++++++++++++++++++
>  3 files changed, 127 insertions(+)
>  create mode 100644 drivers/fpga/versal-fpga.c
> 
> diff --git a/drivers/fpga/Kconfig b/drivers/fpga/Kconfig
> index 33e15058d0dc..92c20b92357a 100644
> --- a/drivers/fpga/Kconfig
> +++ b/drivers/fpga/Kconfig
> @@ -234,4 +234,13 @@ config FPGA_MGR_ZYNQMP_FPGA
>  	  to configure the programmable logic(PL) through PS
>  	  on ZynqMP SoC.
>  
> +config FPGA_MGR_VERSAL_FPGA
> +	tristate "Xilinx Versal FPGA"
> +	depends on ARCH_ZYNQMP || COMPILE_TEST
> +	help
> +	  Select this option to enable FPGA manager driver support for
> +	  Xilinx Versal SoC. This driver uses the firmware interface to
> +	  configure the programmable logic(PL).
> +
> +	  To compile this as a module, choose M here.
>  endif # FPGA
> diff --git a/drivers/fpga/Makefile b/drivers/fpga/Makefile
> index 18dc9885883a..0bff783d1b61 100644
> --- a/drivers/fpga/Makefile
> +++ b/drivers/fpga/Makefile
> @@ -18,6 +18,7 @@ obj-$(CONFIG_FPGA_MGR_TS73XX)		+= ts73xx-fpga.o
>  obj-$(CONFIG_FPGA_MGR_XILINX_SPI)	+= xilinx-spi.o
>  obj-$(CONFIG_FPGA_MGR_ZYNQ_FPGA)	+= zynq-fpga.o
>  obj-$(CONFIG_FPGA_MGR_ZYNQMP_FPGA)	+= zynqmp-fpga.o
> +obj-$(CONFIG_FPGA_MGR_VERSAL_FPGA)      += versal-fpga.o
>  obj-$(CONFIG_ALTERA_PR_IP_CORE)         += altera-pr-ip-core.o
>  obj-$(CONFIG_ALTERA_PR_IP_CORE_PLAT)    += altera-pr-ip-core-plat.o
>  
> diff --git a/drivers/fpga/versal-fpga.c b/drivers/fpga/versal-fpga.c
> new file mode 100644
> index 000000000000..5744e44f981d
> --- /dev/null
> +++ b/drivers/fpga/versal-fpga.c
> @@ -0,0 +1,117 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) 2019-2021 Xilinx, Inc.
> + */
> +
> +#include <linux/dma-mapping.h>
> +#include <linux/fpga/fpga-mgr.h>
> +#include <linux/io.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/of_address.h>
> +#include <linux/string.h>
> +#include <linux/firmware/xlnx-zynqmp.h>
> +
> +/**
> + * struct versal_fpga_priv - Private data structure
> + * @dev:	Device data structure
> + */
> +struct versal_fpga_priv {
> +	struct device *dev;
> +};

Don't you have this pointer already?  What device is this exactly and
why does it differ from the structure it currently lives in?

> +
> +static int versal_fpga_ops_write_init(struct fpga_manager *mgr,
> +				      struct fpga_image_info *info,
> +				      const char *buf, size_t size)
> +{
> +	return 0;
> +}

If you don't need this, why include it?

> +
> +static int versal_fpga_ops_write(struct fpga_manager *mgr,
> +				 const char *buf, size_t size)
> +{
> +	struct versal_fpga_priv *priv;
> +	dma_addr_t dma_addr = 0;
> +	char *kbuf;
> +	int ret;
> +
> +	priv = mgr->priv;
> +
> +	kbuf = dma_alloc_coherent(priv->dev, size, &dma_addr, GFP_KERNEL);
> +	if (!kbuf)
> +		return -ENOMEM;
> +
> +	memcpy(kbuf, buf, size);
> +
> +	wmb(); /* ensure all writes are done before initiate FW call */

What "writes"?  The memcpy above?  Are you _SURE_ that really is correct
here?  This feels wrong.

> +
> +	ret = zynqmp_pm_load_pdi(PDI_SRC_DDR, dma_addr);

If this needs some sort of barrier, shouldn't it be in this call?

> +
> +	dma_free_coherent(priv->dev, size, kbuf, dma_addr);
> +
> +	return ret;
> +}
> +
> +static int versal_fpga_ops_write_complete(struct fpga_manager *mgr,
> +					  struct fpga_image_info *info)
> +{
> +	return 0;
> +}

Again, why have it if it does nothing?

> +
> +static enum fpga_mgr_states versal_fpga_ops_state(struct fpga_manager *mgr)
> +{
> +	return FPGA_MGR_STATE_UNKNOWN;
> +}

Again, is this needed?  If so, then the fpga_manager core needs to be
fixed up :)

> +static const struct fpga_manager_ops versal_fpga_ops = {
> +	.state = versal_fpga_ops_state,
> +	.write_init = versal_fpga_ops_write_init,
> +	.write = versal_fpga_ops_write,
> +	.write_complete = versal_fpga_ops_write_complete,
> +};
> +
> +static int versal_fpga_probe(struct platform_device *pdev)
> +{
> +	struct device *dev = &pdev->dev;
> +	struct versal_fpga_priv *priv;
> +	struct fpga_manager *mgr;
> +	int ret;
> +
> +	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
> +	if (!priv)
> +		return -ENOMEM;
> +
> +	priv->dev = dev;

You save a pointer to a reference counted structure, without
incrementing the reference count.  What could go wrong?  :)

You are getting lucky here, but as stated above, why do you need this
pointer?

thanks,

greg k-h

  reply	other threads:[~2021-05-20  8:49 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-05-20  8:09 [PATCH v6 0/4]Add Bitstream configuration support for Versal Nava kishore Manne
2021-05-20  8:09 ` [PATCH v6 1/4] drivers: firmware: Add PDI load API support Nava kishore Manne
2021-05-20  8:09 ` [PATCH v6 2/4] dt-bindings: fpga: Add binding doc for versal fpga manager Nava kishore Manne
2021-06-02 18:32   ` Rob Herring
2021-05-20  8:09 ` [PATCH v6 3/4] dt-bindings: firmware: Add bindings for xilinx firmware Nava kishore Manne
2021-06-02 18:31   ` Rob Herring
2021-06-04  7:36     ` Nava kishore Manne
2021-05-20  8:09 ` [PATCH v6 4/4] fpga: versal-fpga: Add versal fpga manager driver Nava kishore Manne
2021-05-20  8:48   ` Greg KH [this message]
2021-06-01  6:56     ` Nava kishore Manne
2021-06-01 15:43       ` Moritz Fischer

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=YKYidhc25e4SIwNi@kroah.com \
    --to=gregkh@linuxfoundation.org \
    --cc=amit.sunil.dhamne@xilinx.com \
    --cc=appana.durga.rao@xilinx.com \
    --cc=arnd@arndb.de \
    --cc=chinnikishore369@gmail.com \
    --cc=devicetree@vger.kernel.org \
    --cc=git@xilinx.com \
    --cc=iwamatsu@nigauri.org \
    --cc=lakshmi.sai.krishna.potthuri@xilinx.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-fpga@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mdf@kernel.org \
    --cc=michal.simek@xilinx.com \
    --cc=nava.manne@xilinx.com \
    --cc=rajan.vaja@xilinx.com \
    --cc=ravi.patel@xilinx.com \
    --cc=robh+dt@kernel.org \
    --cc=tejas.patel@xilinx.com \
    --cc=trix@redhat.com \
    --cc=wendy.liang@xilinx.com \
    --cc=zou_wei@huawei.com \
    --subject='Re: [PATCH v6 4/4] fpga: versal-fpga: Add versal fpga manager driver' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).