Linux-remoteproc Archive on lore.kernel.org
 help / color / Atom feed
From: Mathieu Poirier <mathieu.poirier@linaro.org>
To: Alexandre Bailon <abailon@baylibre.com>
Cc: ohad@wizery.com, bjorn.andersson@linaro.org, robh+dt@kernel.org,
	matthias.bgg@gmail.com, linux-remoteproc@vger.kernel.org,
	devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
	linux-mediatek@lists.infradead.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 5/6] remoteproc: mtk_apu: Don't try to use the APU local RAM
Date: Tue, 21 Jul 2020 14:43:32 -0600
Message-ID: <20200721204332.GC1227776@xps15> (raw)
In-Reply-To: <20200713132927.24925-6-abailon@baylibre.com>

On Mon, Jul 13, 2020 at 03:29:26PM +0200, Alexandre Bailon wrote:
> Currently, this local RAM is not accessible from the CPU.
> If the CPU tries to access it, then the CPU will hang.
> 
> Remoteproc may try to use it when it load a firmware
> that has some sections in the local RAM.
> This workarounds the issue by skiping this section.
> 
> Signed-off-by: Alexandre Bailon <abailon@baylibre.com>
> ---
>  drivers/remoteproc/mtk_apu_rproc.c | 14 ++++++++++++++
>  1 file changed, 14 insertions(+)
> 
> diff --git a/drivers/remoteproc/mtk_apu_rproc.c b/drivers/remoteproc/mtk_apu_rproc.c
> index 565b3adca5de..e16d3258a785 100644
> --- a/drivers/remoteproc/mtk_apu_rproc.c
> +++ b/drivers/remoteproc/mtk_apu_rproc.c
> @@ -57,6 +57,9 @@
>  #define CORE_DEFAULT2_SPIDEN			BIT(0)
>  #define CORE_XTENSA_ALTRESETVEC			(0x000001F8)
>  
> +#define DRAM0_START				(0x7ff00000)
> +#define IRAM0_END				(0x7ff80000)
> +
>  struct mtk_vpu_rproc {
>  	struct device *dev;
>  	struct rproc *rproc;
> @@ -139,6 +142,7 @@ static void mtk_vpu_rproc_kick(struct rproc *rproc, int vqid)
>  
>  int mtk_vpu_elf_sanity_check(struct rproc *rproc, const struct firmware *fw)
>  {
> +	struct mtk_vpu_rproc *vpu_rproc = rproc->priv;
>  	const u8 *elf_data = fw->data;
>  	struct elf32_hdr *ehdr;
>  	struct elf32_phdr *phdr;
> @@ -156,6 +160,16 @@ int mtk_vpu_elf_sanity_check(struct rproc *rproc, const struct firmware *fw)
>  		/* Remove empty PT_LOAD section */
>  		if (phdr->p_type == PT_LOAD && !phdr->p_paddr)
>  			phdr->p_type = PT_NULL;
> +		/*
> +		 * Workaround: Currently, the CPU can't access to the APU
> +		 * local RAM. This removes the local RAM section from the
> +		 * firmware. Please note that may cause some issues.
> +		 */
> +		if (phdr->p_paddr >= DRAM0_START && phdr->p_paddr < IRAM0_END) {
> +			dev_warn_once(vpu_rproc->dev,
> +				      "Skipping the APU local RAM section\n");
> +			phdr->p_type = PT_NULL;

We can't selectively decide to not load sections of a program due to a platform
driver shortcoming.  Either a real solution is found or booting the remote
processor is interrupted, with a strong incline toward the former.

I guess you're dealing with tightly coupled memory or on-chip RAM areas -
both are accessed on other platform using ioremap_wc() or devm_ioremap_wc().
You might want to try doing what Suman has done in this patchset [1], with
specific attention to TCMs and SRAM.

Thanks,
Mathieu

[1]. https://patchwork.kernel.org/project/linux-remoteproc/list/?series=310325

> +		}
>  	}
>  
>  	return 0;
> -- 
> 2.26.2
> 

  reply index

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-07-13 13:29 [PATCH 0/6] Add support of mt8183 APU Alexandre Bailon
2020-07-13 13:29 ` [PATCH 1/6] dt bindings: remoteproc: Add bindings for MT8183 APU Alexandre Bailon
2020-07-14 17:19   ` Rob Herring
2020-07-14 17:22   ` Rob Herring
2020-07-13 13:29 ` [PATCH 2/6] remoteproc: Add a remoteproc driver for the MT8183's APU Alexandre Bailon
2020-07-20 22:17   ` Mathieu Poirier
2020-08-06 13:25     ` Alexandre Bailon
2020-07-20 22:19   ` Mathieu Poirier
2020-07-13 13:29 ` [PATCH 3/6] remoteproc: mtk_vpu_rproc: Add support of JTAG Alexandre Bailon
2020-07-21 19:52   ` Mathieu Poirier
2020-08-06 13:49     ` Alexandre Bailon
2020-07-13 13:29 ` [PATCH 4/6] remoteproc: mtk_vpu_rproc: Don't try to load empty PT_LOAD segment Alexandre Bailon
2020-07-21 20:21   ` Mathieu Poirier
2020-07-13 13:29 ` [PATCH 5/6] remoteproc: mtk_apu: Don't try to use the APU local RAM Alexandre Bailon
2020-07-21 20:43   ` Mathieu Poirier [this message]
2020-07-13 13:29 ` [PATCH 6/6] ARM64: mt8183: Add support of APU to mt8183 Alexandre Bailon
2020-07-17 21:02   ` kernel test robot

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=20200721204332.GC1227776@xps15 \
    --to=mathieu.poirier@linaro.org \
    --cc=abailon@baylibre.com \
    --cc=bjorn.andersson@linaro.org \
    --cc=devicetree@vger.kernel.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mediatek@lists.infradead.org \
    --cc=linux-remoteproc@vger.kernel.org \
    --cc=matthias.bgg@gmail.com \
    --cc=ohad@wizery.com \
    --cc=robh+dt@kernel.org \
    /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

Linux-remoteproc Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-remoteproc/0 linux-remoteproc/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-remoteproc linux-remoteproc/ https://lore.kernel.org/linux-remoteproc \
		linux-remoteproc@vger.kernel.org
	public-inbox-index linux-remoteproc

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-remoteproc


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git