| Message ID | 20230324094957.115071-3-biju.das.jz@bp.renesas.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | RZ/G2L DMAC enhancements | expand |
On 24-03-23, 09:49, Biju Das wrote: > The device_tx_status() callback is needed for serial DMA (RZ/G2L > SCIFA). Add support for device_tx_status() callback. > > Based on a patch in the BSP by Long Luu similar to rcar-dmac > <long.luu.ur@renesas.com> > > Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com> > --- > drivers/dma/sh/rz-dmac.c | 169 ++++++++++++++++++++++++++++++++++++++- > 1 file changed, 168 insertions(+), 1 deletion(-) > > diff --git a/drivers/dma/sh/rz-dmac.c b/drivers/dma/sh/rz-dmac.c > index a04a37ce03fd..3625925d9f9f 100644 > --- a/drivers/dma/sh/rz-dmac.c > +++ b/drivers/dma/sh/rz-dmac.c > @@ -110,10 +110,12 @@ struct rz_dmac { > * Registers > */ > > +#define CRTB 0x0020 > #define CHSTAT 0x0024 > #define CHCTRL 0x0028 > #define CHCFG 0x002c > #define NXLA 0x0038 > +#define CRLA 0x003c > > #define DCTRL 0x0000 > > @@ -655,6 +657,171 @@ static void rz_dmac_device_synchronize(struct dma_chan *chan) > rz_dmac_set_dmars_register(dmac, channel->index, 0); > } > > +static unsigned int calculate_total_bytes_in_vd(struct rz_dmac_desc *desc) > +{ > + struct scatterlist *sg, *sgl = desc->sg; > + unsigned int i, size, sg_len = desc->sgcount; > + > + for (i = 0, size = 0, sg = sgl; i < sg_len; i++, sg = sg_next(sg)) > + size += sg_dma_len(sg); for_each_sg() ? > + > + return size; > +} > + > +static unsigned int calculate_residue_bytes_in_vd(struct rz_dmac_chan *channel) > +{ > + struct rz_lmdesc *lmdesc = channel->lmdesc.head; > + struct dma_chan *chan = &channel->vc.chan; > + struct rz_dmac *dmac = to_rz_dmac(chan->device); > + unsigned int residue = 0, i = 0; > + unsigned int crla; > + > + /* get current lmdesc */ > + crla = rz_dmac_ch_readl(channel, CRLA, 1); > + while (!(lmdesc->nxla == crla)) { > + lmdesc++; > + if (lmdesc >= (channel->lmdesc.base + DMAC_NR_LMDESC)) > + lmdesc = channel->lmdesc.base; > + i++; > + /* Not found current lmdesc */ > + if (i > DMAC_NR_LMDESC) > + return 0; > + } > + > + /* Point to current processing lmdesc in hardware */ > + lmdesc++; > + if (lmdesc >= (channel->lmdesc.base + DMAC_NR_LMDESC)) > + lmdesc = channel->lmdesc.base; > + > + /* Calculate residue from next lmdesc to end of virtual desc*/ > + while (lmdesc->chcfg & CHCFG_DEM) { > + lmdesc++; > + if (lmdesc >= (channel->lmdesc.base + DMAC_NR_LMDESC)) > + lmdesc = channel->lmdesc.base; > + residue += lmdesc->tb; > + } > + > + dev_dbg(dmac->dev, "%s: Getting residue is %d\n", __func__, residue); > + > + return residue; > +} > + > +static unsigned int rz_dmac_chan_get_residue(struct rz_dmac_chan *channel, > + dma_cookie_t cookie) > +{ > + struct rz_dmac_desc *current_desc, *desc; > + enum dma_status status; > + unsigned int residue; > + unsigned int crla; > + unsigned int crtb; > + unsigned int i; > + > + /* Get current processing virtual descriptor */ > + current_desc = list_first_entry(&channel->ld_active, > + struct rz_dmac_desc, node); > + if (!current_desc) > + return 0; > + > + /* > + * If the cookie corresponds to a descriptor that has been completed > + * there is no residue. The same check has already been performed by the > + * caller but without holding the channel lock, so the descriptor could > + * now be complete. > + */ > + status = dma_cookie_status(&channel->vc.chan, cookie, NULL); > + if (status == DMA_COMPLETE) > + return 0; > + > + /* > + * If the cookie doesn't correspond to the currently processing virtual > + * descriptor then the descriptor hasn't been processed yet, and the > + * residue is equal to the full descriptor size. > + * Also, a client driver is possible to call this function before > + * rz_dmac_irq_handler_thread() runs. In this case, the running > + * descriptor will be the next descriptor, and the done list will > + * appear. So, if the argument cookie matches the done list's cookie, > + * we can assume the residue is zero. > + */ > + if (cookie != current_desc->vd.tx.cookie) { > + list_for_each_entry(desc, &channel->ld_free, node) { > + if (cookie == desc->vd.tx.cookie) > + return 0; > + } > + > + list_for_each_entry(desc, &channel->ld_queue, node) { > + if (cookie == desc->vd.tx.cookie) > + return calculate_total_bytes_in_vd(desc); > + } > + > + list_for_each_entry(desc, &channel->ld_active, node) { > + if (cookie == desc->vd.tx.cookie) > + return calculate_total_bytes_in_vd(desc); > + } > + > + /* > + * No descriptor found for the cookie, there's thus no residue. > + * This shouldn't happen if the calling driver passes a correct > + * cookie value. > + */ > + WARN(1, "No descriptor for cookie!"); > + return 0; > + } > + > + /* > + * Correspond to the currently processing virtual descriptor > + * > + * Make sure the hardware does not move to next lmdesc > + * while reading the counter. > + * Trying it 3 times should be enough: Initial read, retry, retry > + * for the paranoid. > + * The current lmdesc running in hardware is channel.lmdesc.head > + */ > + for (i = 0; i < 3; i++) { > + crla = rz_dmac_ch_readl(channel, CRLA, 1); > + crtb = rz_dmac_ch_readl(channel, CRTB, 1); > + /* Still the same? */ > + if (crla == rz_dmac_ch_readl(channel, CRLA, 1)) > + break; > + } > + > + WARN_ONCE(i >= 3, "residue might be not continuous!"); > + > + /* > + * Calculate number of byte transferred in processing virtual descriptor > + * One virtual descriptor can have many lmdesc > + */ > + residue = crtb; > + residue += calculate_residue_bytes_in_vd(channel); > + > + return residue; > +} > + > +static enum dma_status rz_dmac_tx_status(struct dma_chan *chan, > + dma_cookie_t cookie, > + struct dma_tx_state *txstate) > +{ > + struct rz_dmac_chan *channel = to_rz_dmac_chan(chan); > + enum dma_status status; > + unsigned int residue; > + unsigned long flags; > + > + status = dma_cookie_status(chan, cookie, txstate); > + if (status == DMA_COMPLETE || !txstate) > + return status; > + > + spin_lock_irqsave(&channel->vc.lock, flags); > + residue = rz_dmac_chan_get_residue(channel, cookie); > + spin_unlock_irqrestore(&channel->vc.lock, flags); > + > + /* if there's no residue, the cookie is complete */ > + if (!residue) > + return DMA_COMPLETE; > + > + dma_set_residue(txstate, residue); > + > + return status; > +} > + > /* > * ----------------------------------------------------------------------------- > * IRQ handling > @@ -937,7 +1104,7 @@ static int rz_dmac_probe(struct platform_device *pdev) > > engine->device_alloc_chan_resources = rz_dmac_alloc_chan_resources; > engine->device_free_chan_resources = rz_dmac_free_chan_resources; > - engine->device_tx_status = dma_cookie_status; > + engine->device_tx_status = rz_dmac_tx_status; > engine->device_prep_slave_sg = rz_dmac_prep_slave_sg; > engine->device_prep_dma_memcpy = rz_dmac_prep_dma_memcpy; > engine->device_config = rz_dmac_config; > -- > 2.25.1
Hi Vinod, Thanks for the feedback. > -----Original Message----- > From: Vinod Koul <vkoul@kernel.org> > Sent: Friday, March 31, 2023 1:17 PM > To: Biju Das <biju.das.jz@bp.renesas.com> > Cc: Prabhakar Mahadev Lad <prabhakar.mahadev-lad.rj@bp.renesas.com>; Geert > Uytterhoeven <geert+renesas@glider.be>; dmaengine@vger.kernel.org; linux- > renesas-soc@vger.kernel.org > Subject: Re: [PATCH 2/3] dmaengine: sh: rz-dmac: Add device_tx_status() > callback > > On 24-03-23, 09:49, Biju Das wrote: > > The device_tx_status() callback is needed for serial DMA (RZ/G2L > > SCIFA). Add support for device_tx_status() callback. > > > > Based on a patch in the BSP by Long Luu similar to rcar-dmac > > <long.luu.ur@renesas.com> > > > > Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com> > > --- > > drivers/dma/sh/rz-dmac.c | 169 > > ++++++++++++++++++++++++++++++++++++++- > > 1 file changed, 168 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/dma/sh/rz-dmac.c b/drivers/dma/sh/rz-dmac.c index > > a04a37ce03fd..3625925d9f9f 100644 > > --- a/drivers/dma/sh/rz-dmac.c > > +++ b/drivers/dma/sh/rz-dmac.c > > @@ -110,10 +110,12 @@ struct rz_dmac { > > * Registers > > */ > > > > +#define CRTB 0x0020 > > #define CHSTAT 0x0024 > > #define CHCTRL 0x0028 > > #define CHCFG 0x002c > > #define NXLA 0x0038 > > +#define CRLA 0x003c > > > > #define DCTRL 0x0000 > > > > @@ -655,6 +657,171 @@ static void rz_dmac_device_synchronize(struct > dma_chan *chan) > > rz_dmac_set_dmars_register(dmac, channel->index, 0); } > > > > +static unsigned int calculate_total_bytes_in_vd(struct rz_dmac_desc > > +*desc) { > > + struct scatterlist *sg, *sgl = desc->sg; > > + unsigned int i, size, sg_len = desc->sgcount; > > + > > + for (i = 0, size = 0, sg = sgl; i < sg_len; i++, sg = sg_next(sg)) > > + size += sg_dma_len(sg); > > for_each_sg() ? Agreed. Much simpler now. Cheers, Biju > > > + > > + return size; > > +} > > + > > +static unsigned int calculate_residue_bytes_in_vd(struct rz_dmac_chan > > +*channel) { > > + struct rz_lmdesc *lmdesc = channel->lmdesc.head; > > + struct dma_chan *chan = &channel->vc.chan; > > + struct rz_dmac *dmac = to_rz_dmac(chan->device); > > + unsigned int residue = 0, i = 0; > > + unsigned int crla; > > + > > + /* get current lmdesc */ > > + crla = rz_dmac_ch_readl(channel, CRLA, 1); > > + while (!(lmdesc->nxla == crla)) { > > + lmdesc++; > > + if (lmdesc >= (channel->lmdesc.base + DMAC_NR_LMDESC)) > > + lmdesc = channel->lmdesc.base; > > + i++; > > + /* Not found current lmdesc */ > > + if (i > DMAC_NR_LMDESC) > > + return 0; > > + } > > + > > + /* Point to current processing lmdesc in hardware */ > > + lmdesc++; > > + if (lmdesc >= (channel->lmdesc.base + DMAC_NR_LMDESC)) > > + lmdesc = channel->lmdesc.base; > > + > > + /* Calculate residue from next lmdesc to end of virtual desc*/ > > + while (lmdesc->chcfg & CHCFG_DEM) { > > + lmdesc++; > > + if (lmdesc >= (channel->lmdesc.base + DMAC_NR_LMDESC)) > > + lmdesc = channel->lmdesc.base; > > + residue += lmdesc->tb; > > + } > > + > > + dev_dbg(dmac->dev, "%s: Getting residue is %d\n", __func__, > > +residue); > > + > > + return residue; > > +} > > + > > +static unsigned int rz_dmac_chan_get_residue(struct rz_dmac_chan > *channel, > > + dma_cookie_t cookie) > > +{ > > + struct rz_dmac_desc *current_desc, *desc; > > + enum dma_status status; > > + unsigned int residue; > > + unsigned int crla; > > + unsigned int crtb; > > + unsigned int i; > > + > > + /* Get current processing virtual descriptor */ > > + current_desc = list_first_entry(&channel->ld_active, > > + struct rz_dmac_desc, node); > > + if (!current_desc) > > + return 0; > > + > > + /* > > + * If the cookie corresponds to a descriptor that has been completed > > + * there is no residue. The same check has already been performed by > the > > + * caller but without holding the channel lock, so the descriptor > could > > + * now be complete. > > + */ > > + status = dma_cookie_status(&channel->vc.chan, cookie, NULL); > > + if (status == DMA_COMPLETE) > > + return 0; > > + > > + /* > > + * If the cookie doesn't correspond to the currently processing > virtual > > + * descriptor then the descriptor hasn't been processed yet, and the > > + * residue is equal to the full descriptor size. > > + * Also, a client driver is possible to call this function before > > + * rz_dmac_irq_handler_thread() runs. In this case, the running > > + * descriptor will be the next descriptor, and the done list will > > + * appear. So, if the argument cookie matches the done list's cookie, > > + * we can assume the residue is zero. > > + */ > > + if (cookie != current_desc->vd.tx.cookie) { > > + list_for_each_entry(desc, &channel->ld_free, node) { > > + if (cookie == desc->vd.tx.cookie) > > + return 0; > > + } > > + > > + list_for_each_entry(desc, &channel->ld_queue, node) { > > + if (cookie == desc->vd.tx.cookie) > > + return calculate_total_bytes_in_vd(desc); > > + } > > + > > + list_for_each_entry(desc, &channel->ld_active, node) { > > + if (cookie == desc->vd.tx.cookie) > > + return calculate_total_bytes_in_vd(desc); > > + } > > + > > + /* > > + * No descriptor found for the cookie, there's thus no residue. > > + * This shouldn't happen if the calling driver passes a correct > > + * cookie value. > > + */ > > + WARN(1, "No descriptor for cookie!"); > > + return 0; > > + } > > + > > + /* > > + * Correspond to the currently processing virtual descriptor > > + * > > + * Make sure the hardware does not move to next lmdesc > > + * while reading the counter. > > + * Trying it 3 times should be enough: Initial read, retry, retry > > + * for the paranoid. > > + * The current lmdesc running in hardware is channel.lmdesc.head > > + */ > > + for (i = 0; i < 3; i++) { > > + crla = rz_dmac_ch_readl(channel, CRLA, 1); > > + crtb = rz_dmac_ch_readl(channel, CRTB, 1); > > + /* Still the same? */ > > + if (crla == rz_dmac_ch_readl(channel, CRLA, 1)) > > + break; > > + } > > + > > + WARN_ONCE(i >= 3, "residue might be not continuous!"); > > + > > + /* > > + * Calculate number of byte transferred in processing virtual > descriptor > > + * One virtual descriptor can have many lmdesc > > + */ > > + residue = crtb; > > + residue += calculate_residue_bytes_in_vd(channel); > > + > > + return residue; > > +} > > + > > +static enum dma_status rz_dmac_tx_status(struct dma_chan *chan, > > + dma_cookie_t cookie, > > + struct dma_tx_state *txstate) > > +{ > > + struct rz_dmac_chan *channel = to_rz_dmac_chan(chan); > > + enum dma_status status; > > + unsigned int residue; > > + unsigned long flags; > > + > > + status = dma_cookie_status(chan, cookie, txstate); > > + if (status == DMA_COMPLETE || !txstate) > > + return status; > > + > > + spin_lock_irqsave(&channel->vc.lock, flags); > > + residue = rz_dmac_chan_get_residue(channel, cookie); > > + spin_unlock_irqrestore(&channel->vc.lock, flags); > > + > > + /* if there's no residue, the cookie is complete */ > > + if (!residue) > > + return DMA_COMPLETE; > > + > > + dma_set_residue(txstate, residue); > > + > > + return status; > > +} > > + > > /* > > * ---------------------------------------------------------------------- > ------- > > * IRQ handling > > @@ -937,7 +1104,7 @@ static int rz_dmac_probe(struct platform_device > > *pdev) > > > > engine->device_alloc_chan_resources = rz_dmac_alloc_chan_resources; > > engine->device_free_chan_resources = rz_dmac_free_chan_resources; > > - engine->device_tx_status = dma_cookie_status; > > + engine->device_tx_status = rz_dmac_tx_status; > > engine->device_prep_slave_sg = rz_dmac_prep_slave_sg; > > engine->device_prep_dma_memcpy = rz_dmac_prep_dma_memcpy; > > engine->device_config = rz_dmac_config; > > -- > > 2.25.1 > > -- > ~Vinod
diff --git a/drivers/dma/sh/rz-dmac.c b/drivers/dma/sh/rz-dmac.c index a04a37ce03fd..3625925d9f9f 100644 --- a/drivers/dma/sh/rz-dmac.c +++ b/drivers/dma/sh/rz-dmac.c @@ -110,10 +110,12 @@ struct rz_dmac { * Registers */ +#define CRTB 0x0020 #define CHSTAT 0x0024 #define CHCTRL 0x0028 #define CHCFG 0x002c #define NXLA 0x0038 +#define CRLA 0x003c #define DCTRL 0x0000 @@ -655,6 +657,171 @@ static void rz_dmac_device_synchronize(struct dma_chan *chan) rz_dmac_set_dmars_register(dmac, channel->index, 0); } +static unsigned int calculate_total_bytes_in_vd(struct rz_dmac_desc *desc) +{ + struct scatterlist *sg, *sgl = desc->sg; + unsigned int i, size, sg_len = desc->sgcount; + + for (i = 0, size = 0, sg = sgl; i < sg_len; i++, sg = sg_next(sg)) + size += sg_dma_len(sg); + + return size; +} + +static unsigned int calculate_residue_bytes_in_vd(struct rz_dmac_chan *channel) +{ + struct rz_lmdesc *lmdesc = channel->lmdesc.head; + struct dma_chan *chan = &channel->vc.chan; + struct rz_dmac *dmac = to_rz_dmac(chan->device); + unsigned int residue = 0, i = 0; + unsigned int crla; + + /* get current lmdesc */ + crla = rz_dmac_ch_readl(channel, CRLA, 1); + while (!(lmdesc->nxla == crla)) { + lmdesc++; + if (lmdesc >= (channel->lmdesc.base + DMAC_NR_LMDESC)) + lmdesc = channel->lmdesc.base; + i++; + /* Not found current lmdesc */ + if (i > DMAC_NR_LMDESC) + return 0; + } + + /* Point to current processing lmdesc in hardware */ + lmdesc++; + if (lmdesc >= (channel->lmdesc.base + DMAC_NR_LMDESC)) + lmdesc = channel->lmdesc.base; + + /* Calculate residue from next lmdesc to end of virtual desc*/ + while (lmdesc->chcfg & CHCFG_DEM) { + lmdesc++; + if (lmdesc >= (channel->lmdesc.base + DMAC_NR_LMDESC)) + lmdesc = channel->lmdesc.base; + residue += lmdesc->tb; + } + + dev_dbg(dmac->dev, "%s: Getting residue is %d\n", __func__, residue); + + return residue; +} + +static unsigned int rz_dmac_chan_get_residue(struct rz_dmac_chan *channel, + dma_cookie_t cookie) +{ + struct rz_dmac_desc *current_desc, *desc; + enum dma_status status; + unsigned int residue; + unsigned int crla; + unsigned int crtb; + unsigned int i; + + /* Get current processing virtual descriptor */ + current_desc = list_first_entry(&channel->ld_active, + struct rz_dmac_desc, node); + if (!current_desc) + return 0; + + /* + * If the cookie corresponds to a descriptor that has been completed + * there is no residue. The same check has already been performed by the + * caller but without holding the channel lock, so the descriptor could + * now be complete. + */ + status = dma_cookie_status(&channel->vc.chan, cookie, NULL); + if (status == DMA_COMPLETE) + return 0; + + /* + * If the cookie doesn't correspond to the currently processing virtual + * descriptor then the descriptor hasn't been processed yet, and the + * residue is equal to the full descriptor size. + * Also, a client driver is possible to call this function before + * rz_dmac_irq_handler_thread() runs. In this case, the running + * descriptor will be the next descriptor, and the done list will + * appear. So, if the argument cookie matches the done list's cookie, + * we can assume the residue is zero. + */ + if (cookie != current_desc->vd.tx.cookie) { + list_for_each_entry(desc, &channel->ld_free, node) { + if (cookie == desc->vd.tx.cookie) + return 0; + } + + list_for_each_entry(desc, &channel->ld_queue, node) { + if (cookie == desc->vd.tx.cookie) + return calculate_total_bytes_in_vd(desc); + } + + list_for_each_entry(desc, &channel->ld_active, node) { + if (cookie == desc->vd.tx.cookie) + return calculate_total_bytes_in_vd(desc); + } + + /* + * No descriptor found for the cookie, there's thus no residue. + * This shouldn't happen if the calling driver passes a correct + * cookie value. + */ + WARN(1, "No descriptor for cookie!"); + return 0; + } + + /* + * Correspond to the currently processing virtual descriptor + * + * Make sure the hardware does not move to next lmdesc + * while reading the counter. + * Trying it 3 times should be enough: Initial read, retry, retry + * for the paranoid. + * The current lmdesc running in hardware is channel.lmdesc.head + */ + for (i = 0; i < 3; i++) { + crla = rz_dmac_ch_readl(channel, CRLA, 1); + crtb = rz_dmac_ch_readl(channel, CRTB, 1); + /* Still the same? */ + if (crla == rz_dmac_ch_readl(channel, CRLA, 1)) + break; + } + + WARN_ONCE(i >= 3, "residue might be not continuous!"); + + /* + * Calculate number of byte transferred in processing virtual descriptor + * One virtual descriptor can have many lmdesc + */ + residue = crtb; + residue += calculate_residue_bytes_in_vd(channel); + + return residue; +} + +static enum dma_status rz_dmac_tx_status(struct dma_chan *chan, + dma_cookie_t cookie, + struct dma_tx_state *txstate) +{ + struct rz_dmac_chan *channel = to_rz_dmac_chan(chan); + enum dma_status status; + unsigned int residue; + unsigned long flags; + + status = dma_cookie_status(chan, cookie, txstate); + if (status == DMA_COMPLETE || !txstate) + return status; + + spin_lock_irqsave(&channel->vc.lock, flags); + residue = rz_dmac_chan_get_residue(channel, cookie); + spin_unlock_irqrestore(&channel->vc.lock, flags); + + /* if there's no residue, the cookie is complete */ + if (!residue) + return DMA_COMPLETE; + + dma_set_residue(txstate, residue); + + return status; +} + /* * ----------------------------------------------------------------------------- * IRQ handling @@ -937,7 +1104,7 @@ static int rz_dmac_probe(struct platform_device *pdev) engine->device_alloc_chan_resources = rz_dmac_alloc_chan_resources; engine->device_free_chan_resources = rz_dmac_free_chan_resources; - engine->device_tx_status = dma_cookie_status; + engine->device_tx_status = rz_dmac_tx_status; engine->device_prep_slave_sg = rz_dmac_prep_slave_sg; engine->device_prep_dma_memcpy = rz_dmac_prep_dma_memcpy; engine->device_config = rz_dmac_config;
The device_tx_status() callback is needed for serial DMA (RZ/G2L SCIFA). Add support for device_tx_status() callback. Based on a patch in the BSP by Long Luu similar to rcar-dmac <long.luu.ur@renesas.com> Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com> --- drivers/dma/sh/rz-dmac.c | 169 ++++++++++++++++++++++++++++++++++++++- 1 file changed, 168 insertions(+), 1 deletion(-)