From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [213.167.242.64]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id EEB463CA487; Tue, 31 Mar 2026 07:43:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=213.167.242.64 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774943015; cv=none; b=dLNWZnNqgwlouN5VIip2zCUjqJ83owzYIy1seATbOniFpLzWImLkaKs37JBNozJ2DPprOhapGITV5SBkEhOGZfqQBV+McTeeUxsWoOqjQWiVC9qHJ2nvyTYNnB3YnCdt04GwmHV27nqOieuVIYLDbH6P6LzlcJq4CHYFevWRybM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774943015; c=relaxed/simple; bh=43u1dXnIBtls8R26Hr7LP/WI8EW8zAs4YwLB0aRmesQ=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=EBhFZixmPz63yNeEFiGUz44gY5LKtkwTVr4hfJcGxGs3GziRxohQz1OSLYbMDkxmXfsfwokkFzGiWP2BQ0fgfasRle5FQrji9/oIRDGDnSzIyHty8qOlOJl+sK9QXHmWkOGK01X438SSmepRKkUY7ZfPNquzS2Lyxvxmv0dxexM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=ideasonboard.com; spf=pass smtp.mailfrom=ideasonboard.com; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b=bFTFyTpJ; arc=none smtp.client-ip=213.167.242.64 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=ideasonboard.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ideasonboard.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="bFTFyTpJ" Received: from ideasonboard.com (net-93-65-100-155.cust.vodafonedsl.it [93.65.100.155]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id DFC1F1E29; Tue, 31 Mar 2026 09:42:02 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1774942923; bh=43u1dXnIBtls8R26Hr7LP/WI8EW8zAs4YwLB0aRmesQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=bFTFyTpJIP8T4N/PiYpDLvAzAjtINzUOqVNNdVRV8iP1WGD5iSEbXoCNebBfOYTd1 MYY9GmzqRbtsV7cTvA71Run0jKAHNKajOLYBz1Uc5oADak/LiBs2Yu+M2O7otmMTiX nCL4dxZ6R1mY0W4DFQPqx8NnZjcpyQ/IBrcBmfI0= Date: Tue, 31 Mar 2026 09:43:22 +0200 From: Jacopo Mondi To: Tommaso Merciai Cc: Jacopo Mondi , Mauro Carvalho Chehab , Laurent Pinchart , Biju Das , Hans Verkuil , Sakari Ailus , Daniel Scally , =?utf-8?Q?Barnab=C3=A1s_P=C5=91cze?= , Lad Prabhakar , linux-media@vger.kernel.org, linux-kernel@vger.kernel.org, Jacopo Mondi Subject: Re: [PATCH 10/14] media: rzg2l-cru: Manually track active slot number Message-ID: References: <20260327-b4-cru-rework-v1-0-3b7d0430f538@ideasonboard.com> <20260327-b4-cru-rework-v1-10-3b7d0430f538@ideasonboard.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: Hi Tommaso On Mon, Mar 30, 2026 at 06:25:59PM +0200, Tommaso Merciai wrote: > > Hi Jacopo, > Thanks for your patch, > > On Fri, Mar 27, 2026 at 06:10:15PM +0100, Jacopo Mondi wrote: > > From: Jacopo Mondi > > > > The CRU cycles over the hardware slots where the destination address for > > the next frame has to be programmed. > > > > The RZ/G2L version of the IP has a register that tells which is the > > last used slot by the hardware but, unfortunately, such register is not > > available on RZ/G3E and RZ/V2H(P). > > > > The driver currently compares the value of the AMnMADRSL/H register > > which report "the memory address which the current video data was > > written to" and compares it with the address programmed in the slots. > > > > This heuristic requires a bit of book keeping and proper locking. As the > > driver handles the FrameEnd interrupt, it's way easier to keep track > > of the slot that has been used by ourselves with a driver variable. > > > > Signed-off-by: Jacopo Mondi > > --- > > .../media/platform/renesas/rzg2l-cru/rzg2l-cru.h | 7 +++-- > > .../media/platform/renesas/rzg2l-cru/rzg2l-video.c | 35 ++++------------------ > > 2 files changed, 10 insertions(+), 32 deletions(-) > > > > diff --git a/drivers/media/platform/renesas/rzg2l-cru/rzg2l-cru.h b/drivers/media/platform/renesas/rzg2l-cru/rzg2l-cru.h > > index b46696a0012b..bc66b0c8c15e 100644 > > --- a/drivers/media/platform/renesas/rzg2l-cru/rzg2l-cru.h > > +++ b/drivers/media/platform/renesas/rzg2l-cru/rzg2l-cru.h > > @@ -108,6 +108,7 @@ struct rzg2l_cru_info { > > * @vdev: V4L2 video device associated with CRU > > * @v4l2_dev: V4L2 device > > * @num_buf: Holds the current number of buffers enabled > > + * > > Maybe you can drop this. > Sorry for the nitpick. Should I ? The rest of the documentation has blank lines that match the ones in the struct members declaration. I think I should try to be consistent. > > > * @svc_channel: SVC0/1/2/3 to use for RZ/G3E > > * @notifier: V4L2 asynchronous subdevs notifier > > * > > @@ -117,9 +118,10 @@ struct rzg2l_cru_info { > > * @mdev_lock: protects the count, notifier and csi members > > * @pad: media pad for the video device entity > > * > > - * @hw_lock: protects the slot counter, hardware programming of > > - * slot addresses and the @buf_addr[] list > > + * @hw_lock: protects the @active_slot counter, hardware programming > > + * of slot addresses and the @buf_addr[] list > > * @buf_addr: Memory addresses where current video data is written > > + * @active_slot: The slot in use > > * > > * @lock: protects @queue > > * @queue: vb2 buffers queue > > @@ -160,6 +162,7 @@ struct rzg2l_cru_dev { > > > > spinlock_t hw_lock; > > dma_addr_t buf_addr[RZG2L_CRU_HW_BUFFER_DEFAULT]; > > + unsigned int active_slot; > > > > struct mutex lock; > > struct vb2_queue queue; > > diff --git a/drivers/media/platform/renesas/rzg2l-cru/rzg2l-video.c b/drivers/media/platform/renesas/rzg2l-cru/rzg2l-video.c > > index 9406a089ec9f..17e0153052e1 100644 > > --- a/drivers/media/platform/renesas/rzg2l-cru/rzg2l-video.c > > +++ b/drivers/media/platform/renesas/rzg2l-cru/rzg2l-video.c > > @@ -637,31 +637,6 @@ irqreturn_t rzg2l_cru_irq(int irq, void *data) > > return IRQ_RETVAL(handled); > > } > > > > -static int rzg3e_cru_get_current_slot(struct rzg2l_cru_dev *cru) > > -{ > > - u64 amnmadrs; > > - int slot; > > - > > - /* > > - * When AMnMADRSL is read, AMnMADRSH of the higher-order > > - * address also latches the address. > > - * > > - * AMnMADRSH must be read after AMnMADRSL has been read. > > - */ > > - amnmadrs = rzg2l_cru_read(cru, AMnMADRSL); > > - amnmadrs |= (u64)rzg2l_cru_read(cru, AMnMADRSH) << 32; > > - > > - /* Ensure amnmadrs is within this buffer range */ > > - for (slot = 0; slot < cru->num_buf; slot++) { > > - if (amnmadrs >= cru->buf_addr[slot] && > > - amnmadrs < cru->buf_addr[slot] + cru->format.sizeimage) > > - return slot; > > - } > > - > > - dev_err(cru->dev, "Invalid MB address 0x%llx (out of range)\n", amnmadrs); > > - return -EINVAL; > > -} > > - > > irqreturn_t rzg3e_cru_irq(int irq, void *data) > > { > > struct rzg2l_cru_dev *cru = data; > > @@ -693,9 +668,8 @@ irqreturn_t rzg3e_cru_irq(int irq, void *data) > > return IRQ_HANDLED; > > } > > > > - slot = rzg3e_cru_get_current_slot(cru); > > - if (slot < 0) > > - return IRQ_HANDLED; > > + slot = cru->active_slot; > > + cru->active_slot = (cru->active_slot + 1) % cru->num_buf; > > > > dev_dbg(cru->dev, "Current written slot: %d\n", slot); > > cru->buf_addr[slot] = 0; > > @@ -762,6 +736,9 @@ static int rzg2l_cru_start_streaming_vq(struct vb2_queue *vq, unsigned int count > > goto assert_aresetn; > > } > > > > + cru->active_slot = 0; > > + cru->sequence = 0; > > + > > /* Allocate scratch buffer */ > > cru->scratch = dma_alloc_coherent(cru->dev, cru->format.sizeimage, > > &cru->scratch_phys, GFP_KERNEL); > > @@ -772,8 +749,6 @@ static int rzg2l_cru_start_streaming_vq(struct vb2_queue *vq, unsigned int count > > goto assert_presetn; > > } > > > > - cru->sequence = 0; > > - > > ret = rzg2l_cru_set_stream(cru, 1); > > if (ret) { > > return_unused_buffers(cru, VB2_BUF_STATE_QUEUED); > > > > -- > > 2.53.0 > > > > Tested-by: Tommaso Merciai > Reviewed-by: Tommaso Merciai > > Kind Regards, > Tommaso > >