From: Baolin Wang <baolin.wang@linaro.org> To: dan.j.williams@intel.com, vkoul@kernel.org Cc: eric.long@spreadtrum.com, broonie@kernel.org, baolin.wang@linaro.org, dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [RESEND,v2] dmaengine: sprd: Support DMA link-list mode Date: Tue, 28 Aug 2018 19:09:07 +0800 [thread overview] Message-ID: <6ce34813e7b3eb25390c6854ee1bc6b618075f20.1535454372.git.baolin.wang@linaro.org> (raw) From: Eric Long <eric.long@spreadtrum.com> The Spreadtrum DMA can support the link-list transaction mode, which means DMA controller can do transaction one by one automatically once we linked these transaction by link-list register. Signed-off-by: Eric Long <eric.long@spreadtrum.com> Signed-off-by: Baolin Wang <baolin.wang@linaro.org> --- Changes since v1: - Remove sprd_dma_fill_chn_desc() function. - Remove the redundant validation of 'sglen' in sprd_dma_fill_linklist_desc(). - Add some comments make code more clear. - Fix the typos. --- drivers/dma/sprd-dma.c | 81 ++++++++++++++++++++++++++++++++++++++---- include/linux/dma/sprd-dma.h | 69 +++++++++++++++++++++++++++++++++++ 2 files changed, 143 insertions(+), 7 deletions(-) diff --git a/drivers/dma/sprd-dma.c b/drivers/dma/sprd-dma.c index 55df0d4..38d4e4f 100644 --- a/drivers/dma/sprd-dma.c +++ b/drivers/dma/sprd-dma.c @@ -68,6 +68,7 @@ /* SPRD_DMA_CHN_CFG register definition */ #define SPRD_DMA_CHN_EN BIT(0) +#define SPRD_DMA_LINKLIST_EN BIT(4) #define SPRD_DMA_WAIT_BDONE_OFFSET 24 #define SPRD_DMA_DONOT_WAIT_BDONE 1 @@ -103,7 +104,7 @@ #define SPRD_DMA_REQ_MODE_MASK GENMASK(1, 0) #define SPRD_DMA_FIX_SEL_OFFSET 21 #define SPRD_DMA_FIX_EN_OFFSET 20 -#define SPRD_DMA_LLIST_END_OFFSET 19 +#define SPRD_DMA_LLIST_END BIT(19) #define SPRD_DMA_FRG_LEN_MASK GENMASK(16, 0) /* SPRD_DMA_CHN_BLK_LEN register definition */ @@ -164,6 +165,7 @@ struct sprd_dma_desc { struct sprd_dma_chn { struct virt_dma_chan vc; void __iomem *chn_base; + struct sprd_dma_linklist linklist; struct dma_slave_config slave_cfg; u32 chn_num; u32 dev_id; @@ -582,7 +584,8 @@ static int sprd_dma_get_step(enum dma_slave_buswidth buswidth) } static int sprd_dma_fill_desc(struct dma_chan *chan, - struct sprd_dma_desc *sdesc, + struct sprd_dma_chn_hw *hw, + unsigned int sglen, int sg_index, dma_addr_t src, dma_addr_t dst, u32 len, enum dma_transfer_direction dir, unsigned long flags, @@ -590,7 +593,6 @@ static int sprd_dma_fill_desc(struct dma_chan *chan, { struct sprd_dma_dev *sdev = to_sprd_dma_dev(chan); struct sprd_dma_chn *schan = to_sprd_dma_chan(chan); - struct sprd_dma_chn_hw *hw = &sdesc->chn_hw; u32 req_mode = (flags >> SPRD_DMA_REQ_SHIFT) & SPRD_DMA_REQ_MODE_MASK; u32 int_mode = flags & SPRD_DMA_INT_MASK; int src_datawidth, dst_datawidth, src_step, dst_step; @@ -670,12 +672,52 @@ static int sprd_dma_fill_desc(struct dma_chan *chan, temp |= (src_step & SPRD_DMA_TRSF_STEP_MASK) << SPRD_DMA_SRC_TRSF_STEP_OFFSET; hw->trsf_step = temp; + /* link-list configuration */ + if (schan->linklist.phy_addr) { + if (sg_index == sglen - 1) + hw->frg_len |= SPRD_DMA_LLIST_END; + + hw->cfg |= SPRD_DMA_LINKLIST_EN; + + /* link-list index */ + temp = (sg_index + 1) % sglen; + /* Next link-list configuration's physical address offset */ + temp = temp * sizeof(*hw) + SPRD_DMA_CHN_SRC_ADDR; + /* + * Set the link-list pointer point to next link-list + * configuration's physical address. + */ + hw->llist_ptr = schan->linklist.phy_addr + temp; + } else { + hw->llist_ptr = 0; + } + hw->frg_step = 0; hw->src_blk_step = 0; hw->des_blk_step = 0; return 0; } +static int sprd_dma_fill_linklist_desc(struct dma_chan *chan, + unsigned int sglen, int sg_index, + dma_addr_t src, dma_addr_t dst, u32 len, + enum dma_transfer_direction dir, + unsigned long flags, + struct dma_slave_config *slave_cfg) +{ + struct sprd_dma_chn *schan = to_sprd_dma_chan(chan); + struct sprd_dma_chn_hw *hw; + + if (!schan->linklist.virt_addr) + return -EINVAL; + + hw = (struct sprd_dma_chn_hw *)(schan->linklist.virt_addr + + sg_index * sizeof(*hw)); + + return sprd_dma_fill_desc(chan, hw, sglen, sg_index, src, dst, len, + dir, flags, slave_cfg); +} + static struct dma_async_tx_descriptor * sprd_dma_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src, size_t len, unsigned long flags) @@ -744,10 +786,20 @@ static int sprd_dma_fill_desc(struct dma_chan *chan, u32 len = 0; int ret, i; - /* TODO: now we only support one sg for each DMA configuration. */ - if (!is_slave_direction(dir) || sglen > 1) + if (!is_slave_direction(dir)) return NULL; + if (context) { + struct sprd_dma_linklist *ll_cfg = + (struct sprd_dma_linklist *)context; + + schan->linklist.phy_addr = ll_cfg->phy_addr; + schan->linklist.virt_addr = ll_cfg->virt_addr; + } else { + schan->linklist.phy_addr = 0; + schan->linklist.virt_addr = 0; + } + sdesc = kzalloc(sizeof(*sdesc), GFP_NOWAIT); if (!sdesc) return NULL; @@ -762,10 +814,25 @@ static int sprd_dma_fill_desc(struct dma_chan *chan, src = slave_cfg->src_addr; dst = sg_dma_address(sg); } + + /* + * The link-list mode needs at least 2 link-list + * configurations. If there is only one sg, it doesn't + * need to fill the link-list configuration. + */ + if (sglen < 2) + break; + + ret = sprd_dma_fill_linklist_desc(chan, sglen, i, src, dst, len, + dir, flags, slave_cfg); + if (ret) { + kfree(sdesc); + return NULL; + } } - ret = sprd_dma_fill_desc(chan, sdesc, src, dst, len, dir, flags, - slave_cfg); + ret = sprd_dma_fill_desc(chan, &sdesc->chn_hw, 0, 0, src, dst, len, + dir, flags, slave_cfg); if (ret) { kfree(sdesc); return NULL; diff --git a/include/linux/dma/sprd-dma.h b/include/linux/dma/sprd-dma.h index b0115e3..b42b80e5 100644 --- a/include/linux/dma/sprd-dma.h +++ b/include/linux/dma/sprd-dma.h @@ -58,4 +58,73 @@ enum sprd_dma_int_type { SPRD_DMA_CFGERR_INT, }; +/* + * struct sprd_dma_linklist - DMA link-list address structure + * @virt_addr: link-list virtual address to configure link-list node + * @phy_addr: link-list physical address to link DMA transfer + * + * The Spreadtrum DMA controller supports the link-list mode, that means slaves + * can supply several groups configurations (each configuration represents one + * DMA transfer) saved in memory, and DMA controller will link these groups + * configurations by writing the physical address of each configuration into the + * link-list register. + * + * Just as shown below, the link-list pointer register will be pointed to the + * physical address of 'configuration 1', and the 'configuration 1' link-list + * pointer will be pointed to 'configuration 2', and so on. + * Once trigger the DMA transfer, the DMA controller will load 'configuration + * 1' to its registers automatically, after 'configuration 1' transaction is + * done, DMA controller will load 'configuration 2' automatically, until all + * DMA transactions are done. + * + * Note: The last link-list pointer should point to the physical address + * of 'configuration 1', which can avoid DMA controller loads incorrect + * configuration when the last configuration transaction is done. + * + * DMA controller linklist memory + * ====================== ----------------------- + *| | | configuration 1 |<--- + *| DMA controller | ------->| | | + *| | | | | | + *| | | | | | + *| | | | | | + *| linklist pointer reg |---- ----| linklist pointer | | + * ====================== | ----------------------- | + * | | + * | ----------------------- | + * | | configuration 2 | | + * --->| | | + * | | | + * | | | + * | | | + * ----| linklist pointer | | + * | ----------------------- | + * | | + * | ----------------------- | + * | | configuration 3 | | + * --->| | | + * | | | + * | . | | + * . | + * . | + * . | + * | . | + * | ----------------------- | + * | | configuration n | | + * --->| | | + * | | | + * | | | + * | | | + * | linklist pointer |---- + * ----------------------- + * + * To support the link-list mode, DMA slaves should allocate one segment memory + * from always-on IRAM or dma coherent memory to store these groups of DMA + * configuration, and pass the virtual and physical address to DMA controller. + */ +struct sprd_dma_linklist { + unsigned long virt_addr; + phys_addr_t phy_addr; +}; + #endif
WARNING: multiple messages have this Message-ID (diff)
From: Baolin Wang <baolin.wang@linaro.org> To: dan.j.williams@intel.com, vkoul@kernel.org Cc: eric.long@spreadtrum.com, broonie@kernel.org, baolin.wang@linaro.org, dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [RESEND PATCH v2] dmaengine: sprd: Support DMA link-list mode Date: Tue, 28 Aug 2018 19:09:07 +0800 [thread overview] Message-ID: <6ce34813e7b3eb25390c6854ee1bc6b618075f20.1535454372.git.baolin.wang@linaro.org> (raw) From: Eric Long <eric.long@spreadtrum.com> The Spreadtrum DMA can support the link-list transaction mode, which means DMA controller can do transaction one by one automatically once we linked these transaction by link-list register. Signed-off-by: Eric Long <eric.long@spreadtrum.com> Signed-off-by: Baolin Wang <baolin.wang@linaro.org> --- Changes since v1: - Remove sprd_dma_fill_chn_desc() function. - Remove the redundant validation of 'sglen' in sprd_dma_fill_linklist_desc(). - Add some comments make code more clear. - Fix the typos. --- drivers/dma/sprd-dma.c | 81 ++++++++++++++++++++++++++++++++++++++---- include/linux/dma/sprd-dma.h | 69 +++++++++++++++++++++++++++++++++++ 2 files changed, 143 insertions(+), 7 deletions(-) diff --git a/drivers/dma/sprd-dma.c b/drivers/dma/sprd-dma.c index 55df0d4..38d4e4f 100644 --- a/drivers/dma/sprd-dma.c +++ b/drivers/dma/sprd-dma.c @@ -68,6 +68,7 @@ /* SPRD_DMA_CHN_CFG register definition */ #define SPRD_DMA_CHN_EN BIT(0) +#define SPRD_DMA_LINKLIST_EN BIT(4) #define SPRD_DMA_WAIT_BDONE_OFFSET 24 #define SPRD_DMA_DONOT_WAIT_BDONE 1 @@ -103,7 +104,7 @@ #define SPRD_DMA_REQ_MODE_MASK GENMASK(1, 0) #define SPRD_DMA_FIX_SEL_OFFSET 21 #define SPRD_DMA_FIX_EN_OFFSET 20 -#define SPRD_DMA_LLIST_END_OFFSET 19 +#define SPRD_DMA_LLIST_END BIT(19) #define SPRD_DMA_FRG_LEN_MASK GENMASK(16, 0) /* SPRD_DMA_CHN_BLK_LEN register definition */ @@ -164,6 +165,7 @@ struct sprd_dma_desc { struct sprd_dma_chn { struct virt_dma_chan vc; void __iomem *chn_base; + struct sprd_dma_linklist linklist; struct dma_slave_config slave_cfg; u32 chn_num; u32 dev_id; @@ -582,7 +584,8 @@ static int sprd_dma_get_step(enum dma_slave_buswidth buswidth) } static int sprd_dma_fill_desc(struct dma_chan *chan, - struct sprd_dma_desc *sdesc, + struct sprd_dma_chn_hw *hw, + unsigned int sglen, int sg_index, dma_addr_t src, dma_addr_t dst, u32 len, enum dma_transfer_direction dir, unsigned long flags, @@ -590,7 +593,6 @@ static int sprd_dma_fill_desc(struct dma_chan *chan, { struct sprd_dma_dev *sdev = to_sprd_dma_dev(chan); struct sprd_dma_chn *schan = to_sprd_dma_chan(chan); - struct sprd_dma_chn_hw *hw = &sdesc->chn_hw; u32 req_mode = (flags >> SPRD_DMA_REQ_SHIFT) & SPRD_DMA_REQ_MODE_MASK; u32 int_mode = flags & SPRD_DMA_INT_MASK; int src_datawidth, dst_datawidth, src_step, dst_step; @@ -670,12 +672,52 @@ static int sprd_dma_fill_desc(struct dma_chan *chan, temp |= (src_step & SPRD_DMA_TRSF_STEP_MASK) << SPRD_DMA_SRC_TRSF_STEP_OFFSET; hw->trsf_step = temp; + /* link-list configuration */ + if (schan->linklist.phy_addr) { + if (sg_index == sglen - 1) + hw->frg_len |= SPRD_DMA_LLIST_END; + + hw->cfg |= SPRD_DMA_LINKLIST_EN; + + /* link-list index */ + temp = (sg_index + 1) % sglen; + /* Next link-list configuration's physical address offset */ + temp = temp * sizeof(*hw) + SPRD_DMA_CHN_SRC_ADDR; + /* + * Set the link-list pointer point to next link-list + * configuration's physical address. + */ + hw->llist_ptr = schan->linklist.phy_addr + temp; + } else { + hw->llist_ptr = 0; + } + hw->frg_step = 0; hw->src_blk_step = 0; hw->des_blk_step = 0; return 0; } +static int sprd_dma_fill_linklist_desc(struct dma_chan *chan, + unsigned int sglen, int sg_index, + dma_addr_t src, dma_addr_t dst, u32 len, + enum dma_transfer_direction dir, + unsigned long flags, + struct dma_slave_config *slave_cfg) +{ + struct sprd_dma_chn *schan = to_sprd_dma_chan(chan); + struct sprd_dma_chn_hw *hw; + + if (!schan->linklist.virt_addr) + return -EINVAL; + + hw = (struct sprd_dma_chn_hw *)(schan->linklist.virt_addr + + sg_index * sizeof(*hw)); + + return sprd_dma_fill_desc(chan, hw, sglen, sg_index, src, dst, len, + dir, flags, slave_cfg); +} + static struct dma_async_tx_descriptor * sprd_dma_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src, size_t len, unsigned long flags) @@ -744,10 +786,20 @@ static int sprd_dma_fill_desc(struct dma_chan *chan, u32 len = 0; int ret, i; - /* TODO: now we only support one sg for each DMA configuration. */ - if (!is_slave_direction(dir) || sglen > 1) + if (!is_slave_direction(dir)) return NULL; + if (context) { + struct sprd_dma_linklist *ll_cfg = + (struct sprd_dma_linklist *)context; + + schan->linklist.phy_addr = ll_cfg->phy_addr; + schan->linklist.virt_addr = ll_cfg->virt_addr; + } else { + schan->linklist.phy_addr = 0; + schan->linklist.virt_addr = 0; + } + sdesc = kzalloc(sizeof(*sdesc), GFP_NOWAIT); if (!sdesc) return NULL; @@ -762,10 +814,25 @@ static int sprd_dma_fill_desc(struct dma_chan *chan, src = slave_cfg->src_addr; dst = sg_dma_address(sg); } + + /* + * The link-list mode needs at least 2 link-list + * configurations. If there is only one sg, it doesn't + * need to fill the link-list configuration. + */ + if (sglen < 2) + break; + + ret = sprd_dma_fill_linklist_desc(chan, sglen, i, src, dst, len, + dir, flags, slave_cfg); + if (ret) { + kfree(sdesc); + return NULL; + } } - ret = sprd_dma_fill_desc(chan, sdesc, src, dst, len, dir, flags, - slave_cfg); + ret = sprd_dma_fill_desc(chan, &sdesc->chn_hw, 0, 0, src, dst, len, + dir, flags, slave_cfg); if (ret) { kfree(sdesc); return NULL; diff --git a/include/linux/dma/sprd-dma.h b/include/linux/dma/sprd-dma.h index b0115e3..b42b80e5 100644 --- a/include/linux/dma/sprd-dma.h +++ b/include/linux/dma/sprd-dma.h @@ -58,4 +58,73 @@ enum sprd_dma_int_type { SPRD_DMA_CFGERR_INT, }; +/* + * struct sprd_dma_linklist - DMA link-list address structure + * @virt_addr: link-list virtual address to configure link-list node + * @phy_addr: link-list physical address to link DMA transfer + * + * The Spreadtrum DMA controller supports the link-list mode, that means slaves + * can supply several groups configurations (each configuration represents one + * DMA transfer) saved in memory, and DMA controller will link these groups + * configurations by writing the physical address of each configuration into the + * link-list register. + * + * Just as shown below, the link-list pointer register will be pointed to the + * physical address of 'configuration 1', and the 'configuration 1' link-list + * pointer will be pointed to 'configuration 2', and so on. + * Once trigger the DMA transfer, the DMA controller will load 'configuration + * 1' to its registers automatically, after 'configuration 1' transaction is + * done, DMA controller will load 'configuration 2' automatically, until all + * DMA transactions are done. + * + * Note: The last link-list pointer should point to the physical address + * of 'configuration 1', which can avoid DMA controller loads incorrect + * configuration when the last configuration transaction is done. + * + * DMA controller linklist memory + * ====================== ----------------------- + *| | | configuration 1 |<--- + *| DMA controller | ------->| | | + *| | | | | | + *| | | | | | + *| | | | | | + *| linklist pointer reg |---- ----| linklist pointer | | + * ====================== | ----------------------- | + * | | + * | ----------------------- | + * | | configuration 2 | | + * --->| | | + * | | | + * | | | + * | | | + * ----| linklist pointer | | + * | ----------------------- | + * | | + * | ----------------------- | + * | | configuration 3 | | + * --->| | | + * | | | + * | . | | + * . | + * . | + * . | + * | . | + * | ----------------------- | + * | | configuration n | | + * --->| | | + * | | | + * | | | + * | | | + * | linklist pointer |---- + * ----------------------- + * + * To support the link-list mode, DMA slaves should allocate one segment memory + * from always-on IRAM or dma coherent memory to store these groups of DMA + * configuration, and pass the virtual and physical address to DMA controller. + */ +struct sprd_dma_linklist { + unsigned long virt_addr; + phys_addr_t phy_addr; +}; + #endif -- 1.7.9.5
next reply other threads:[~2018-08-28 11:09 UTC|newest] Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top 2018-08-28 11:09 Baolin Wang [this message] 2018-08-28 11:09 ` [RESEND PATCH v2] dmaengine: sprd: Support DMA link-list mode Baolin Wang 2018-09-03 11:30 [RESEND,v2] " Vinod Koul 2018-09-03 11:30 ` [RESEND PATCH v2] " Vinod
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=6ce34813e7b3eb25390c6854ee1bc6b618075f20.1535454372.git.baolin.wang@linaro.org \ --to=baolin.wang@linaro.org \ --cc=broonie@kernel.org \ --cc=dan.j.williams@intel.com \ --cc=dmaengine@vger.kernel.org \ --cc=eric.long@spreadtrum.com \ --cc=linux-kernel@vger.kernel.org \ --cc=vkoul@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: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.