The below patch series are to support AxiDMA running on Intel KeemBay SoC.
The base driver is dw-axi-dmac. This driver only support DMA memory copy
transfers. Code refactoring is needed so that additional features can be
supported.
The features added in this patch series are:
- Replacing Linked List with virtual descriptor management.
- Remove unrelated hw desc stuff from dma memory pool.
- Manage dma memory pool alloc/destroy based on channel activity.
- Support dmaengine device_sync() callback.
- Support dmaengine device_config().
- Support dmaengine device_prep_slave_sg().
- Support dmaengine device_prep_dma_cyclic().
- Support of_dma_controller_register().
- Support burst residue granularity.
- Support Intel KeemBay AxiDMA registers.
- Support Intel KeemBay AxiDMA device handshake.
- Support Intel KeemBay AxiDMA BYTE and HALFWORD device operation.
- Add constraint to Max segment size.
- Virtually split the linked-list.
This patch series are tested on Intel KeemBay platform.
v8:
- Rebased to kernel v5.11-rc1.
- Added reviewed-by tag from Rob.
v7:
- Added 'allOf' and '$ref:dma-controller.yaml#' in DT binding.
- Removed the dma-channels common description in DT binding.
- Removed the default fields in DT binding.
v6:
- Removed 'allOf' cases in DT binding.
- Added '>' at the end of the email address.
- Removed additional '|' at the start of description.
- Fixed space indent.
- Added proper constraint in DT binding.
- Removed second example in DT binding.
v5:
- Added comment to the Apb registers used by Intel KeemBay Soc.
- Renamed "hs_num" to "handshake_num".
- Conditional check for the compatible property and return error
instead of printing warning.
- Added patch 16th to virtually split the linked-list as per
request from ALSA team.
v4:
- Fixed bot found errors running make_dt_binding_check.
- Added minItems: 1 to the YAML schemas DT binding.
- Updated "reg" field to the YAML schemas DT binding.
v3:
- Added additionalProperties: false to the YAML schemas DT binding.
- Reordered patch sequence for patch 10th, 11th and 12th so that
DT binding come first, follow by adding Intel KeemBay SoC registers
and update .compatible field.
- Checked txstate NULL condition.
- Created helper function dw_axi_dma_set_hw_desc() to handle common code.
v2:
- Rebased to v5.10-rc1 kernel.
- Added support for dmaengine device_config().
- Added support for dmaengine device_prep_slave_sg().
- Added support for dmaengine device_prep_dma_cyclic().
- Added support for of_dma_controller_register().
- Added support for burst residue granularity.
- Added support for Intel KeemBay AxiDMA registers.
- Added support for Intel KeemBay AxiDMA device handshake.
- Added support for Intel KeemBay AxiDMA BYTE and HALFWORD device operation.
- Added constraint to Max segment size.
v1:
- Initial version. Patch on top of dw-axi-dma driver. This version improve
the descriptor management by replacing Linked List Item (LLI) with
virtual descriptor management, only allocate hardware LLI memories from
DMA memory pool, manage DMA memory pool alloc/destroy based on channel
activity and to support device_sync callback.
Sia Jee Heng (16):
dt-bindings: dma: Add YAML schemas for dw-axi-dmac
dmaengine: dw-axi-dmac: simplify descriptor management
dmaengine: dw-axi-dmac: move dma_pool_create() to
alloc_chan_resources()
dmaengine: dw-axi-dmac: Add device_synchronize() callback
dmaengine: dw-axi-dmac: Add device_config operation
dmaengine: dw-axi-dmac: Support device_prep_slave_sg
dmaegine: dw-axi-dmac: Support device_prep_dma_cyclic()
dmaengine: dw-axi-dmac: Support of_dma_controller_register()
dmaengine: dw-axi-dmac: Support burst residue granularity
dt-binding: dma: dw-axi-dmac: Add support for Intel KeemBay AxiDMA
dmaengine: dw-axi-dmac: Add Intel KeemBay DMA register fields
dmaengine: dw-axi-dmac: Add Intel KeemBay AxiDMA support
dmaengine: dw-axi-dmac: Add Intel KeemBay AxiDMA handshake
dmaengine: dw-axi-dmac: Add Intel KeemBay AxiDMA BYTE and HALFWORD
registers
dmaengine: dw-axi-dmac: Set constraint to the Max segment size
dmaengine: dw-axi-dmac: Virtually split the linked-list
.../bindings/dma/snps,dw-axi-dmac.txt | 39 -
.../bindings/dma/snps,dw-axi-dmac.yaml | 126 ++++
.../dma/dw-axi-dmac/dw-axi-dmac-platform.c | 710 +++++++++++++++---
drivers/dma/dw-axi-dmac/dw-axi-dmac.h | 34 +-
4 files changed, 775 insertions(+), 134 deletions(-)
delete mode 100644 Documentation/devicetree/bindings/dma/snps,dw-axi-dmac.txt
create mode 100644 Documentation/devicetree/bindings/dma/snps,dw-axi-dmac.yaml
base-commit: dea8dcf2a9fa8cc540136a6cd885c3beece16ec3
--
2.18.0
Add support for device_prep_dma_cyclic() callback function to benefit
DMA cyclic client, for example ALSA.
Existing AxiDMA driver only support data transfer between memory to memory.
Data transfer between device to memory and memory to device in cyclic mode
would failed if this interface is not supported by the AxiDMA driver.
Reviewed-by: Andy Shevchenko <[email protected]>
Signed-off-by: Sia Jee Heng <[email protected]>
---
.../dma/dw-axi-dmac/dw-axi-dmac-platform.c | 111 ++++++++++++++++--
drivers/dma/dw-axi-dmac/dw-axi-dmac.h | 2 +
2 files changed, 106 insertions(+), 7 deletions(-)
diff --git a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
index 7ff30b0f44ed..a76299360f69 100644
--- a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
+++ b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
@@ -15,6 +15,8 @@
#include <linux/err.h>
#include <linux/interrupt.h>
#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/io-64-nonatomic-lo-hi.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
@@ -549,6 +551,64 @@ static int dw_axi_dma_set_hw_desc(struct axi_dma_chan *chan,
return 0;
}
+static struct dma_async_tx_descriptor *
+dw_axi_dma_chan_prep_cyclic(struct dma_chan *dchan, dma_addr_t dma_addr,
+ size_t buf_len, size_t period_len,
+ enum dma_transfer_direction direction,
+ unsigned long flags)
+{
+ struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
+ struct axi_dma_hw_desc *hw_desc = NULL;
+ struct axi_dma_desc *desc = NULL;
+ dma_addr_t src_addr = dma_addr;
+ u32 num_periods = buf_len / period_len;
+ unsigned int i;
+ int status;
+ u64 llp = 0;
+ u8 lms = 0; /* Select AXI0 master for LLI fetching */
+
+ desc = axi_desc_alloc(num_periods);
+ if (unlikely(!desc))
+ goto err_desc_get;
+
+ chan->direction = direction;
+ desc->chan = chan;
+ chan->cyclic = true;
+
+ for (i = 0; i < num_periods; i++) {
+ hw_desc = &desc->hw_desc[i];
+
+ status = dw_axi_dma_set_hw_desc(chan, hw_desc, src_addr,
+ period_len);
+ if (status < 0)
+ goto err_desc_get;
+
+ /* Set end-of-link to the linked descriptor, so that cyclic
+ * callback function can be triggered during interrupt.
+ */
+ set_desc_last(hw_desc);
+
+ src_addr += period_len;
+ }
+
+ llp = desc->hw_desc[0].llp;
+
+ /* Managed transfer list */
+ do {
+ hw_desc = &desc->hw_desc[--num_periods];
+ write_desc_llp(hw_desc, llp | lms);
+ llp = hw_desc->llp;
+ } while (num_periods);
+
+ return vchan_tx_prep(&chan->vc, &desc->vd, flags);
+
+err_desc_get:
+ if (desc)
+ axi_desc_put(desc);
+
+ return NULL;
+}
+
static struct dma_async_tx_descriptor *
dw_axi_dma_chan_prep_slave_sg(struct dma_chan *dchan, struct scatterlist *sgl,
unsigned int sg_len,
@@ -773,8 +833,13 @@ static noinline void axi_chan_handle_err(struct axi_dma_chan *chan, u32 status)
static void axi_chan_block_xfer_complete(struct axi_dma_chan *chan)
{
+ int count = atomic_read(&chan->descs_allocated);
+ struct axi_dma_hw_desc *hw_desc;
+ struct axi_dma_desc *desc;
struct virt_dma_desc *vd;
unsigned long flags;
+ u64 llp;
+ int i;
spin_lock_irqsave(&chan->vc.lock, flags);
if (unlikely(axi_chan_is_hw_enable(chan))) {
@@ -785,12 +850,32 @@ static void axi_chan_block_xfer_complete(struct axi_dma_chan *chan)
/* The completed descriptor currently is in the head of vc list */
vd = vchan_next_desc(&chan->vc);
- /* Remove the completed descriptor from issued list before completing */
- list_del(&vd->node);
- vchan_cookie_complete(vd);
- /* Submit queued descriptors after processing the completed ones */
- axi_chan_start_first_queued(chan);
+ if (chan->cyclic) {
+ vchan_cyclic_callback(vd);
+ desc = vd_to_axi_desc(vd);
+ if (desc) {
+ llp = lo_hi_readq(chan->chan_regs + CH_LLP);
+ for (i = 0; i < count; i++) {
+ hw_desc = &desc->hw_desc[i];
+ if (hw_desc->llp == llp) {
+ axi_chan_irq_clear(chan, hw_desc->lli->status_lo);
+ hw_desc->lli->ctl_hi |= CH_CTL_H_LLI_VALID;
+ desc->completed_blocks = i;
+ break;
+ }
+ }
+
+ axi_chan_enable(chan);
+ }
+ } else {
+ /* Remove the completed descriptor from issued list before completing */
+ list_del(&vd->node);
+ vchan_cookie_complete(vd);
+
+ /* Submit queued descriptors after processing the completed ones */
+ axi_chan_start_first_queued(chan);
+ }
spin_unlock_irqrestore(&chan->vc.lock, flags);
}
@@ -830,15 +915,25 @@ static irqreturn_t dw_axi_dma_interrupt(int irq, void *dev_id)
static int dma_chan_terminate_all(struct dma_chan *dchan)
{
struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
+ u32 chan_active = BIT(chan->id) << DMAC_CHAN_EN_SHIFT;
unsigned long flags;
+ u32 val;
+ int ret;
LIST_HEAD(head);
- spin_lock_irqsave(&chan->vc.lock, flags);
-
axi_chan_disable(chan);
+ ret = readl_poll_timeout_atomic(chan->chip->regs + DMAC_CHEN, val,
+ !(val & chan_active), 1000, 10000);
+ if (ret == -ETIMEDOUT)
+ dev_warn(dchan2dev(dchan),
+ "%s failed to stop\n", axi_chan_name(chan));
+
+ spin_lock_irqsave(&chan->vc.lock, flags);
+
vchan_get_all_descriptors(&chan->vc, &head);
+ chan->cyclic = false;
spin_unlock_irqrestore(&chan->vc.lock, flags);
vchan_dma_desc_free_list(&chan->vc, &head);
@@ -1090,6 +1185,7 @@ static int dw_probe(struct platform_device *pdev)
/* Set capabilities */
dma_cap_set(DMA_MEMCPY, dw->dma.cap_mask);
dma_cap_set(DMA_SLAVE, dw->dma.cap_mask);
+ dma_cap_set(DMA_CYCLIC, dw->dma.cap_mask);
/* DMA capabilities */
dw->dma.chancnt = hdata->nr_channels;
@@ -1113,6 +1209,7 @@ static int dw_probe(struct platform_device *pdev)
dw->dma.device_synchronize = dw_axi_dma_synchronize;
dw->dma.device_config = dw_axi_dma_chan_slave_config;
dw->dma.device_prep_slave_sg = dw_axi_dma_chan_prep_slave_sg;
+ dw->dma.device_prep_dma_cyclic = dw_axi_dma_chan_prep_cyclic;
platform_set_drvdata(pdev, chip);
diff --git a/drivers/dma/dw-axi-dmac/dw-axi-dmac.h b/drivers/dma/dw-axi-dmac/dw-axi-dmac.h
index ac49f2e14b0c..a26b0a242a93 100644
--- a/drivers/dma/dw-axi-dmac/dw-axi-dmac.h
+++ b/drivers/dma/dw-axi-dmac/dw-axi-dmac.h
@@ -45,6 +45,7 @@ struct axi_dma_chan {
struct axi_dma_desc *desc;
struct dma_slave_config config;
enum dma_transfer_direction direction;
+ bool cyclic;
/* these other elements are all protected by vc.lock */
bool is_paused;
};
@@ -93,6 +94,7 @@ struct axi_dma_desc {
struct virt_dma_desc vd;
struct axi_dma_chan *chan;
+ u32 completed_blocks;
};
static inline struct device *dchan2dev(struct dma_chan *dchan)
--
2.18.0
Add support for of_dma_controller_register() so that DMA clients
can pass in device handshake number to the AxiDMA driver.
DMA clients shall code the device handshake number in the Device tree.
When DMA activities are needed, DMA clients shall invoke OF helper
function to pass in the device handshake number to the AxiDMA.
Without register to the of_dma_controller_register(), data transfer
between memory to device and device to memory operations would failed.
Reviewed-by: Andy Shevchenko <[email protected]>
Signed-off-by: Sia Jee Heng <[email protected]>
---
.../dma/dw-axi-dmac/dw-axi-dmac-platform.c | 26 +++++++++++++++++++
drivers/dma/dw-axi-dmac/dw-axi-dmac.h | 1 +
2 files changed, 27 insertions(+)
diff --git a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
index a76299360f69..a8b6c8c8ef58 100644
--- a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
+++ b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
@@ -20,6 +20,7 @@
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
+#include <linux/of_dma.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/property.h>
@@ -1044,6 +1045,22 @@ static int __maybe_unused axi_dma_runtime_resume(struct device *dev)
return axi_dma_resume(chip);
}
+static struct dma_chan *dw_axi_dma_of_xlate(struct of_phandle_args *dma_spec,
+ struct of_dma *ofdma)
+{
+ struct dw_axi_dma *dw = ofdma->of_dma_data;
+ struct axi_dma_chan *chan;
+ struct dma_chan *dchan;
+
+ dchan = dma_get_any_slave_channel(&dw->dma);
+ if (!dchan)
+ return NULL;
+
+ chan = dchan_to_axi_dma_chan(dchan);
+ chan->hw_handshake_num = dma_spec->args[0];
+ return dchan;
+}
+
static int parse_device_properties(struct axi_dma_chip *chip)
{
struct device *dev = chip->dev;
@@ -1233,6 +1250,13 @@ static int dw_probe(struct platform_device *pdev)
if (ret)
goto err_pm_disable;
+ /* Register with OF helpers for DMA lookups */
+ ret = of_dma_controller_register(pdev->dev.of_node,
+ dw_axi_dma_of_xlate, dw);
+ if (ret < 0)
+ dev_warn(&pdev->dev,
+ "Failed to register OF DMA controller, fallback to MEM_TO_MEM mode\n");
+
dev_info(chip->dev, "DesignWare AXI DMA Controller, %d channels\n",
dw->hdata->nr_channels);
@@ -1266,6 +1290,8 @@ static int dw_remove(struct platform_device *pdev)
devm_free_irq(chip->dev, chip->irq, chip);
+ of_dma_controller_free(chip->dev->of_node);
+
list_for_each_entry_safe(chan, _chan, &dw->dma.channels,
vc.chan.device_node) {
list_del(&chan->vc.chan.device_node);
diff --git a/drivers/dma/dw-axi-dmac/dw-axi-dmac.h b/drivers/dma/dw-axi-dmac/dw-axi-dmac.h
index a26b0a242a93..3498bef5453b 100644
--- a/drivers/dma/dw-axi-dmac/dw-axi-dmac.h
+++ b/drivers/dma/dw-axi-dmac/dw-axi-dmac.h
@@ -37,6 +37,7 @@ struct axi_dma_chan {
struct axi_dma_chip *chip;
void __iomem *chan_regs;
u8 id;
+ u8 hw_handshake_num;
atomic_t descs_allocated;
struct dma_pool *desc_pool;
--
2.18.0
Add support for Intel KeemBay DMA registers. These registers are required
to run data transfer between device to memory and memory to device on Intel
KeemBay SoC.
Reviewed-by: Andy Shevchenko <[email protected]>
Signed-off-by: Sia Jee Heng <[email protected]>
---
drivers/dma/dw-axi-dmac/dw-axi-dmac.h | 14 ++++++++++++++
1 file changed, 14 insertions(+)
diff --git a/drivers/dma/dw-axi-dmac/dw-axi-dmac.h b/drivers/dma/dw-axi-dmac/dw-axi-dmac.h
index 46baf93de617..3a357f7fda02 100644
--- a/drivers/dma/dw-axi-dmac/dw-axi-dmac.h
+++ b/drivers/dma/dw-axi-dmac/dw-axi-dmac.h
@@ -63,6 +63,7 @@ struct axi_dma_chip {
struct device *dev;
int irq;
void __iomem *regs;
+ void __iomem *apb_regs;
struct clk *core_clk;
struct clk *cfgr_clk;
struct dw_axi_dma *dw;
@@ -169,6 +170,19 @@ static inline struct axi_dma_chan *dchan_to_axi_dma_chan(struct dma_chan *dchan)
#define CH_INTSIGNAL_ENA 0x090 /* R/W Chan Interrupt Signal Enable */
#define CH_INTCLEAR 0x098 /* W Chan Interrupt Clear */
+/* These Apb registers are used by Intel KeemBay SoC */
+#define DMAC_APB_CFG 0x000 /* DMAC Apb Configuration Register */
+#define DMAC_APB_STAT 0x004 /* DMAC Apb Status Register */
+#define DMAC_APB_DEBUG_STAT_0 0x008 /* DMAC Apb Debug Status Register 0 */
+#define DMAC_APB_DEBUG_STAT_1 0x00C /* DMAC Apb Debug Status Register 1 */
+#define DMAC_APB_HW_HS_SEL_0 0x010 /* DMAC Apb HW HS register 0 */
+#define DMAC_APB_HW_HS_SEL_1 0x014 /* DMAC Apb HW HS register 1 */
+#define DMAC_APB_LPI 0x018 /* DMAC Apb Low Power Interface Reg */
+#define DMAC_APB_BYTE_WR_CH_EN 0x01C /* DMAC Apb Byte Write Enable */
+#define DMAC_APB_HALFWORD_WR_CH_EN 0x020 /* DMAC Halfword write enables */
+
+#define UNUSED_CHANNEL 0x3F /* Set unused DMA channel to 0x3F */
+#define MAX_BLOCK_SIZE 0x1000 /* 1024 blocks * 4 bytes data width */
/* DMAC_CFG */
#define DMAC_EN_POS 0
--
2.18.0
Add support for Intel KeemBay AxiDMA to the .compatible field.
The AxiDMA Apb region will be accessible if the compatible string
matches the "intel,kmb-axi-dma".
Reviewed-by: Andy Shevchenko <[email protected]>
Signed-off-by: Sia Jee Heng <[email protected]>
---
drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
index 830d3de76abd..062d27c61983 100644
--- a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
+++ b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
@@ -1160,6 +1160,7 @@ static int parse_device_properties(struct axi_dma_chip *chip)
static int dw_probe(struct platform_device *pdev)
{
+ struct device_node *node = pdev->dev.of_node;
struct axi_dma_chip *chip;
struct resource *mem;
struct dw_axi_dma *dw;
@@ -1192,6 +1193,12 @@ static int dw_probe(struct platform_device *pdev)
if (IS_ERR(chip->regs))
return PTR_ERR(chip->regs);
+ if (of_device_is_compatible(node, "intel,kmb-axi-dma")) {
+ chip->apb_regs = devm_platform_ioremap_resource(pdev, 1);
+ if (IS_ERR(chip->apb_regs))
+ return PTR_ERR(chip->apb_regs);
+ }
+
chip->core_clk = devm_clk_get(chip->dev, "core-clk");
if (IS_ERR(chip->core_clk))
return PTR_ERR(chip->core_clk);
@@ -1336,6 +1343,7 @@ static const struct dev_pm_ops dw_axi_dma_pm_ops = {
static const struct of_device_id dw_dma_of_id_table[] = {
{ .compatible = "snps,axi-dma-1.01a" },
+ { .compatible = "intel,kmb-axi-dma" },
{}
};
MODULE_DEVICE_TABLE(of, dw_dma_of_id_table);
--
2.18.0
Add support for Intel KeemBay AxiDMA device handshake programming.
Device handshake number passed in to the AxiDMA shall be written to
the Intel KeemBay AxiDMA hardware handshake registers before DMA
operations are started.
Reviewed-by: Andy Shevchenko <[email protected]>
Signed-off-by: Sia Jee Heng <[email protected]>
---
.../dma/dw-axi-dmac/dw-axi-dmac-platform.c | 52 +++++++++++++++++++
1 file changed, 52 insertions(+)
diff --git a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
index 062d27c61983..5e77eb3d040f 100644
--- a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
+++ b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
@@ -445,6 +445,48 @@ static void dma_chan_free_chan_resources(struct dma_chan *dchan)
pm_runtime_put(chan->chip->dev);
}
+static int dw_axi_dma_set_hw_channel(struct axi_dma_chip *chip,
+ u32 handshake_num, bool set)
+{
+ unsigned long start = 0;
+ unsigned long reg_value;
+ unsigned long reg_mask;
+ unsigned long reg_set;
+ unsigned long mask;
+ unsigned long val;
+
+ if (!chip->apb_regs)
+ return -ENODEV;
+
+ /*
+ * An unused DMA channel has a default value of 0x3F.
+ * Lock the DMA channel by assign a handshake number to the channel.
+ * Unlock the DMA channel by assign 0x3F to the channel.
+ */
+ if (set) {
+ reg_set = UNUSED_CHANNEL;
+ val = handshake_num;
+ } else {
+ reg_set = handshake_num;
+ val = UNUSED_CHANNEL;
+ }
+
+ reg_value = lo_hi_readq(chip->apb_regs + DMAC_APB_HW_HS_SEL_0);
+
+ for_each_set_clump8(start, reg_mask, ®_value, 64) {
+ if (reg_mask == reg_set) {
+ mask = GENMASK_ULL(start + 7, start);
+ reg_value &= ~mask;
+ reg_value |= rol64(val, start);
+ lo_hi_writeq(reg_value,
+ chip->apb_regs + DMAC_APB_HW_HS_SEL_0);
+ break;
+ }
+ }
+
+ return 0;
+}
+
/*
* If DW_axi_dmac sees CHx_CTL.ShadowReg_Or_LLI_Last bit of the fetched LLI
* as 1, it understands that the current block is the final block in the
@@ -626,6 +668,9 @@ dw_axi_dma_chan_prep_cyclic(struct dma_chan *dchan, dma_addr_t dma_addr,
llp = hw_desc->llp;
} while (num_periods);
+ if (dw_axi_dma_set_hw_channel(chan->chip, chan->hw_handshake_num, true))
+ goto err_desc_get;
+
return vchan_tx_prep(&chan->vc, &desc->vd, flags);
err_desc_get:
@@ -684,6 +729,9 @@ dw_axi_dma_chan_prep_slave_sg(struct dma_chan *dchan, struct scatterlist *sgl,
llp = hw_desc->llp;
} while (sg_len);
+ if (dw_axi_dma_set_hw_channel(chan->chip, chan->hw_handshake_num, true))
+ goto err_desc_get;
+
return vchan_tx_prep(&chan->vc, &desc->vd, flags);
err_desc_get:
@@ -959,6 +1007,10 @@ static int dma_chan_terminate_all(struct dma_chan *dchan)
dev_warn(dchan2dev(dchan),
"%s failed to stop\n", axi_chan_name(chan));
+ if (chan->direction != DMA_MEM_TO_MEM)
+ dw_axi_dma_set_hw_channel(chan->chip,
+ chan->hw_handshake_num, false);
+
spin_lock_irqsave(&chan->vc.lock, flags);
vchan_get_all_descriptors(&chan->vc, &head);
--
2.18.0
Add support for DMA_RESIDUE_GRANULARITY_BURST so that AxiDMA can report
DMA residue.
Existing AxiDMA driver only support data transfer between
memory to memory operation, therefore reporting DMA residue
to the DMA clients is not supported.
Reporting DMA residue to the DMA clients is important as DMA clients
shall invoke dmaengine_tx_status() to understand the number of bytes
been transferred so that the buffer pointer can be updated accordingly.
Reviewed-by: Andy Shevchenko <[email protected]>
Signed-off-by: Sia Jee Heng <[email protected]>
---
.../dma/dw-axi-dmac/dw-axi-dmac-platform.c | 43 ++++++++++++++++---
drivers/dma/dw-axi-dmac/dw-axi-dmac.h | 2 +
2 files changed, 38 insertions(+), 7 deletions(-)
diff --git a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
index a8b6c8c8ef58..830d3de76abd 100644
--- a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
+++ b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
@@ -265,14 +265,36 @@ dma_chan_tx_status(struct dma_chan *dchan, dma_cookie_t cookie,
struct dma_tx_state *txstate)
{
struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
- enum dma_status ret;
+ struct virt_dma_desc *vdesc;
+ enum dma_status status;
+ u32 completed_length;
+ unsigned long flags;
+ u32 completed_blocks;
+ size_t bytes = 0;
+ u32 length;
+ u32 len;
- ret = dma_cookie_status(dchan, cookie, txstate);
+ status = dma_cookie_status(dchan, cookie, txstate);
+ if (status == DMA_COMPLETE || !txstate)
+ return status;
- if (chan->is_paused && ret == DMA_IN_PROGRESS)
- ret = DMA_PAUSED;
+ spin_lock_irqsave(&chan->vc.lock, flags);
- return ret;
+ vdesc = vchan_find_desc(&chan->vc, cookie);
+ if (vdesc) {
+ length = vd_to_axi_desc(vdesc)->length;
+ completed_blocks = vd_to_axi_desc(vdesc)->completed_blocks;
+ len = vd_to_axi_desc(vdesc)->hw_desc[0].len;
+ completed_length = completed_blocks * len;
+ bytes = length - completed_length;
+ } else {
+ bytes = vd_to_axi_desc(vdesc)->length;
+ }
+
+ spin_unlock_irqrestore(&chan->vc.lock, flags);
+ dma_set_residue(txstate, bytes);
+
+ return status;
}
static void write_desc_llp(struct axi_dma_hw_desc *desc, dma_addr_t adr)
@@ -549,6 +571,7 @@ static int dw_axi_dma_set_hw_desc(struct axi_dma_chan *chan,
set_desc_src_master(hw_desc);
+ hw_desc->len = len;
return 0;
}
@@ -575,6 +598,7 @@ dw_axi_dma_chan_prep_cyclic(struct dma_chan *dchan, dma_addr_t dma_addr,
chan->direction = direction;
desc->chan = chan;
chan->cyclic = true;
+ desc->length = 0;
for (i = 0; i < num_periods; i++) {
hw_desc = &desc->hw_desc[i];
@@ -584,6 +608,7 @@ dw_axi_dma_chan_prep_cyclic(struct dma_chan *dchan, dma_addr_t dma_addr,
if (status < 0)
goto err_desc_get;
+ desc->length += hw_desc->len;
/* Set end-of-link to the linked descriptor, so that cyclic
* callback function can be triggered during interrupt.
*/
@@ -636,6 +661,7 @@ dw_axi_dma_chan_prep_slave_sg(struct dma_chan *dchan, struct scatterlist *sgl,
goto err_desc_get;
desc->chan = chan;
+ desc->length = 0;
for_each_sg(sgl, sg, sg_len, i) {
mem = sg_dma_address(sg);
@@ -645,6 +671,7 @@ dw_axi_dma_chan_prep_slave_sg(struct dma_chan *dchan, struct scatterlist *sgl,
status = dw_axi_dma_set_hw_desc(chan, hw_desc, mem, len);
if (status < 0)
goto err_desc_get;
+ desc->length += hw_desc->len;
}
/* Set end-of-link to the last link descriptor of list */
@@ -690,6 +717,7 @@ dma_chan_prep_dma_memcpy(struct dma_chan *dchan, dma_addr_t dst_adr,
desc->chan = chan;
num = 0;
+ desc->length = 0;
while (len) {
xfer_len = len;
@@ -742,7 +770,8 @@ dma_chan_prep_dma_memcpy(struct dma_chan *dchan, dma_addr_t dst_adr,
set_desc_src_master(hw_desc);
set_desc_dest_master(hw_desc, desc);
-
+ hw_desc->len = xfer_len;
+ desc->length += hw_desc->len;
/* update the length and addresses for the next loop cycle */
len -= xfer_len;
dst_adr += xfer_len;
@@ -1210,7 +1239,7 @@ static int dw_probe(struct platform_device *pdev)
dw->dma.dst_addr_widths = AXI_DMA_BUSWIDTHS;
dw->dma.directions = BIT(DMA_MEM_TO_MEM);
dw->dma.directions |= BIT(DMA_MEM_TO_DEV) | BIT(DMA_DEV_TO_MEM);
- dw->dma.residue_granularity = DMA_RESIDUE_GRANULARITY_DESCRIPTOR;
+ dw->dma.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
dw->dma.dev = chip->dev;
dw->dma.device_tx_status = dma_chan_tx_status;
diff --git a/drivers/dma/dw-axi-dmac/dw-axi-dmac.h b/drivers/dma/dw-axi-dmac/dw-axi-dmac.h
index 3498bef5453b..46baf93de617 100644
--- a/drivers/dma/dw-axi-dmac/dw-axi-dmac.h
+++ b/drivers/dma/dw-axi-dmac/dw-axi-dmac.h
@@ -88,6 +88,7 @@ struct __packed axi_dma_lli {
struct axi_dma_hw_desc {
struct axi_dma_lli *lli;
dma_addr_t llp;
+ u32 len;
};
struct axi_dma_desc {
@@ -96,6 +97,7 @@ struct axi_dma_desc {
struct virt_dma_desc vd;
struct axi_dma_chan *chan;
u32 completed_blocks;
+ u32 length;
};
static inline struct device *dchan2dev(struct dma_chan *dchan)
--
2.18.0
Add support for DMA Scatter-Gather (SG) constraint so that DMA clients can
handle the AxiDMA limitation.
Without supporting DMA constraint the default Max segment size reported by
dmaengine is 64KB, which is not supported by Intel KeemBay AxiDMA.
Reviewed-by: Andy Shevchenko <[email protected]>
Signed-off-by: Sia Jee Heng <[email protected]>
---
drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c | 8 ++++++++
drivers/dma/dw-axi-dmac/dw-axi-dmac.h | 1 +
2 files changed, 9 insertions(+)
diff --git a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
index ab145a84b0c0..58845b058d9d 100644
--- a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
+++ b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
@@ -12,6 +12,7 @@
#include <linux/device.h>
#include <linux/dmaengine.h>
#include <linux/dmapool.h>
+#include <linux/dma-mapping.h>
#include <linux/err.h>
#include <linux/interrupt.h>
#include <linux/io.h>
@@ -1350,6 +1351,13 @@ static int dw_probe(struct platform_device *pdev)
dw->dma.device_prep_slave_sg = dw_axi_dma_chan_prep_slave_sg;
dw->dma.device_prep_dma_cyclic = dw_axi_dma_chan_prep_cyclic;
+ /*
+ * Synopsis DesignWare AxiDMA datasheet mentioned Maximum
+ * supported blocks is 1024. Device register width is 4 bytes.
+ * Therefore, set constraint to 1024 * 4.
+ */
+ dw->dma.dev->dma_parms = &dw->dma_parms;
+ dma_set_max_seg_size(&pdev->dev, MAX_BLOCK_SIZE);
platform_set_drvdata(pdev, chip);
pm_runtime_enable(chip->dev);
diff --git a/drivers/dma/dw-axi-dmac/dw-axi-dmac.h b/drivers/dma/dw-axi-dmac/dw-axi-dmac.h
index 3a357f7fda02..1e937ea2a96d 100644
--- a/drivers/dma/dw-axi-dmac/dw-axi-dmac.h
+++ b/drivers/dma/dw-axi-dmac/dw-axi-dmac.h
@@ -54,6 +54,7 @@ struct axi_dma_chan {
struct dw_axi_dma {
struct dma_device dma;
struct dw_axi_dma_hcfg *hdata;
+ struct device_dma_parameters dma_parms;
/* channels */
struct axi_dma_chan *chan;
--
2.18.0
AxiDMA driver exposed the dma_set_max_seg_size() to the DMAENGINE.
It shall helps the DMA clients to create size-optimized linked-list
for the controller.
However, there are certain situations where DMA client might not be
abled to benefit from the dma_get_max_seg_size() if the segment size
can't meet the nature of the DMA client's operation.
In the case of ALSA operation, ALSA application and driver expecting
to run in a period of larger than 10ms regardless of the bit depth.
With this large period, there is a strong request to split the linked-list
in the AxiDMA driver.
Signed-off-by: Sia Jee Heng <[email protected]>
---
.../dma/dw-axi-dmac/dw-axi-dmac-platform.c | 111 ++++++++++++++----
drivers/dma/dw-axi-dmac/dw-axi-dmac.h | 1 +
2 files changed, 92 insertions(+), 20 deletions(-)
diff --git a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
index 58845b058d9d..c17b96245f13 100644
--- a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
+++ b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
@@ -576,6 +576,11 @@ static int dw_axi_dma_set_hw_desc(struct axi_dma_chan *chan,
if (mem_width > DWAXIDMAC_TRANS_WIDTH_32)
mem_width = DWAXIDMAC_TRANS_WIDTH_32;
+ if (!IS_ALIGNED(mem_addr, 4)) {
+ dev_err(chan->chip->dev, "invalid buffer alignment\n");
+ return -EINVAL;
+ }
+
switch (chan->direction) {
case DMA_MEM_TO_DEV:
reg_width = __ffs(chan->config.dst_addr_width);
@@ -637,6 +642,35 @@ static int dw_axi_dma_set_hw_desc(struct axi_dma_chan *chan,
return 0;
}
+static size_t calculate_block_len(struct axi_dma_chan *chan,
+ dma_addr_t dma_addr, size_t buf_len,
+ enum dma_transfer_direction direction)
+{
+ u32 data_width, reg_width, mem_width;
+ size_t axi_block_ts, block_len;
+
+ axi_block_ts = chan->chip->dw->hdata->block_size[chan->id];
+
+ switch (direction) {
+ case DMA_MEM_TO_DEV:
+ data_width = BIT(chan->chip->dw->hdata->m_data_width);
+ mem_width = __ffs(data_width | dma_addr | buf_len);
+ if (mem_width > DWAXIDMAC_TRANS_WIDTH_32)
+ mem_width = DWAXIDMAC_TRANS_WIDTH_32;
+
+ block_len = axi_block_ts << mem_width;
+ break;
+ case DMA_DEV_TO_MEM:
+ reg_width = __ffs(chan->config.src_addr_width);
+ block_len = axi_block_ts << reg_width;
+ break;
+ default:
+ block_len = 0;
+ }
+
+ return block_len;
+}
+
static struct dma_async_tx_descriptor *
dw_axi_dma_chan_prep_cyclic(struct dma_chan *dchan, dma_addr_t dma_addr,
size_t buf_len, size_t period_len,
@@ -647,13 +681,27 @@ dw_axi_dma_chan_prep_cyclic(struct dma_chan *dchan, dma_addr_t dma_addr,
struct axi_dma_hw_desc *hw_desc = NULL;
struct axi_dma_desc *desc = NULL;
dma_addr_t src_addr = dma_addr;
- u32 num_periods = buf_len / period_len;
+ u32 num_periods, num_segments;
+ size_t axi_block_len;
+ u32 total_segments;
+ u32 segment_len;
unsigned int i;
int status;
u64 llp = 0;
u8 lms = 0; /* Select AXI0 master for LLI fetching */
- desc = axi_desc_alloc(num_periods);
+ num_periods = buf_len / period_len;
+
+ axi_block_len = calculate_block_len(chan, dma_addr, buf_len, direction);
+ if (axi_block_len == 0)
+ return NULL;
+
+ num_segments = DIV_ROUND_UP(period_len, axi_block_len);
+ segment_len = DIV_ROUND_UP(period_len, num_segments);
+
+ total_segments = num_periods * num_segments;
+
+ desc = axi_desc_alloc(total_segments);
if (unlikely(!desc))
goto err_desc_get;
@@ -661,12 +709,13 @@ dw_axi_dma_chan_prep_cyclic(struct dma_chan *dchan, dma_addr_t dma_addr,
desc->chan = chan;
chan->cyclic = true;
desc->length = 0;
+ desc->period_len = period_len;
- for (i = 0; i < num_periods; i++) {
+ for (i = 0; i < total_segments; i++) {
hw_desc = &desc->hw_desc[i];
status = dw_axi_dma_set_hw_desc(chan, hw_desc, src_addr,
- period_len);
+ segment_len);
if (status < 0)
goto err_desc_get;
@@ -676,17 +725,17 @@ dw_axi_dma_chan_prep_cyclic(struct dma_chan *dchan, dma_addr_t dma_addr,
*/
set_desc_last(hw_desc);
- src_addr += period_len;
+ src_addr += segment_len;
}
llp = desc->hw_desc[0].llp;
/* Managed transfer list */
do {
- hw_desc = &desc->hw_desc[--num_periods];
+ hw_desc = &desc->hw_desc[--total_segments];
write_desc_llp(hw_desc, llp | lms);
llp = hw_desc->llp;
- } while (num_periods);
+ } while (total_segments);
if (dw_axi_dma_set_hw_channel(chan->chip, chan->hw_handshake_num, true))
goto err_desc_get;
@@ -709,9 +758,13 @@ dw_axi_dma_chan_prep_slave_sg(struct dma_chan *dchan, struct scatterlist *sgl,
struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
struct axi_dma_hw_desc *hw_desc = NULL;
struct axi_dma_desc *desc = NULL;
+ u32 num_segments, segment_len;
+ unsigned int loop = 0;
struct scatterlist *sg;
+ size_t axi_block_len;
+ u32 len, num_sgs = 0;
unsigned int i;
- u32 mem, len;
+ dma_addr_t mem;
int status;
u64 llp = 0;
u8 lms = 0; /* Select AXI0 master for LLI fetching */
@@ -719,35 +772,51 @@ dw_axi_dma_chan_prep_slave_sg(struct dma_chan *dchan, struct scatterlist *sgl,
if (unlikely(!is_slave_direction(direction) || !sg_len))
return NULL;
- chan->direction = direction;
+ mem = sg_dma_address(sgl);
+ len = sg_dma_len(sgl);
+
+ axi_block_len = calculate_block_len(chan, mem, len, direction);
+ if (axi_block_len == 0)
+ return NULL;
- desc = axi_desc_alloc(sg_len);
+ for_each_sg(sgl, sg, sg_len, i)
+ num_sgs += DIV_ROUND_UP(sg_dma_len(sg), axi_block_len);
+
+ desc = axi_desc_alloc(num_sgs);
if (unlikely(!desc))
goto err_desc_get;
desc->chan = chan;
desc->length = 0;
+ chan->direction = direction;
for_each_sg(sgl, sg, sg_len, i) {
mem = sg_dma_address(sg);
len = sg_dma_len(sg);
- hw_desc = &desc->hw_desc[i];
-
- status = dw_axi_dma_set_hw_desc(chan, hw_desc, mem, len);
- if (status < 0)
- goto err_desc_get;
- desc->length += hw_desc->len;
+ num_segments = DIV_ROUND_UP(sg_dma_len(sg), axi_block_len);
+ segment_len = DIV_ROUND_UP(sg_dma_len(sg), num_segments);
+
+ do {
+ hw_desc = &desc->hw_desc[loop++];
+ status = dw_axi_dma_set_hw_desc(chan, hw_desc, mem, segment_len);
+ if (status < 0)
+ goto err_desc_get;
+
+ desc->length += hw_desc->len;
+ len -= segment_len;
+ mem += segment_len;
+ } while (len >= segment_len);
}
/* Set end-of-link to the last link descriptor of list */
- set_desc_last(&desc->hw_desc[sg_len - 1]);
+ set_desc_last(&desc->hw_desc[num_sgs - 1]);
/* Managed transfer list */
do {
- hw_desc = &desc->hw_desc[--sg_len];
+ hw_desc = &desc->hw_desc[--num_sgs];
write_desc_llp(hw_desc, llp | lms);
llp = hw_desc->llp;
- } while (sg_len);
+ } while (num_sgs);
if (dw_axi_dma_set_hw_channel(chan->chip, chan->hw_handshake_num, true))
goto err_desc_get;
@@ -950,7 +1019,6 @@ static void axi_chan_block_xfer_complete(struct axi_dma_chan *chan)
vd = vchan_next_desc(&chan->vc);
if (chan->cyclic) {
- vchan_cyclic_callback(vd);
desc = vd_to_axi_desc(vd);
if (desc) {
llp = lo_hi_readq(chan->chan_regs + CH_LLP);
@@ -960,6 +1028,9 @@ static void axi_chan_block_xfer_complete(struct axi_dma_chan *chan)
axi_chan_irq_clear(chan, hw_desc->lli->status_lo);
hw_desc->lli->ctl_hi |= CH_CTL_H_LLI_VALID;
desc->completed_blocks = i;
+
+ if (((hw_desc->len * (i + 1)) % desc->period_len) == 0)
+ vchan_cyclic_callback(vd);
break;
}
}
diff --git a/drivers/dma/dw-axi-dmac/dw-axi-dmac.h b/drivers/dma/dw-axi-dmac/dw-axi-dmac.h
index 1e937ea2a96d..b69897887c76 100644
--- a/drivers/dma/dw-axi-dmac/dw-axi-dmac.h
+++ b/drivers/dma/dw-axi-dmac/dw-axi-dmac.h
@@ -100,6 +100,7 @@ struct axi_dma_desc {
struct axi_dma_chan *chan;
u32 completed_blocks;
u32 length;
+ u32 period_len;
};
static inline struct device *dchan2dev(struct dma_chan *dchan)
--
2.18.0
Add support for Intel KeemBay AxiDMA BYTE and HALFWORD registers
programming.
Intel KeemBay AxiDMA supports data transfer between device to memory
and memory to device operations.
This code is needed by I2C, I3C, I2S, SPI and UART which uses FIFO
size of 8bits and 16bits to perform memory to device data transfer
operation. 0-padding functionality is provided to avoid
pre-processing of data on CPU.
Reviewed-by: Andy Shevchenko <[email protected]>
Signed-off-by: Sia Jee Heng <[email protected]>
---
.../dma/dw-axi-dmac/dw-axi-dmac-platform.c | 44 ++++++++++++++++---
1 file changed, 39 insertions(+), 5 deletions(-)
diff --git a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
index 5e77eb3d040f..ab145a84b0c0 100644
--- a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
+++ b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
@@ -312,7 +312,7 @@ static void axi_chan_block_xfer_start(struct axi_dma_chan *chan,
struct axi_dma_desc *first)
{
u32 priority = chan->chip->dw->hdata->priority[chan->id];
- u32 reg, irq_mask;
+ u32 reg, irq_mask, reg_width, offset, val;
u8 lms = 0; /* Select AXI0 master for LLI fetching */
if (unlikely(axi_chan_is_hw_enable(chan))) {
@@ -334,6 +334,25 @@ static void axi_chan_block_xfer_start(struct axi_dma_chan *chan,
DWAXIDMAC_HS_SEL_HW << CH_CFG_H_HS_SEL_SRC_POS);
switch (chan->direction) {
case DMA_MEM_TO_DEV:
+ if (chan->chip->apb_regs) {
+ reg_width = __ffs(chan->config.dst_addr_width);
+ /*
+ * Configure Byte and Halfword register
+ * for MEM_TO_DEV only.
+ */
+ if (reg_width == DWAXIDMAC_TRANS_WIDTH_16) {
+ offset = DMAC_APB_HALFWORD_WR_CH_EN;
+ val = ioread32(chan->chip->apb_regs + offset);
+ val |= BIT(chan->id);
+ iowrite32(val, chan->chip->apb_regs + offset);
+ } else if (reg_width == DWAXIDMAC_TRANS_WIDTH_8) {
+ offset = DMAC_APB_BYTE_WR_CH_EN;
+ val = ioread32(chan->chip->apb_regs + offset);
+ val |= BIT(chan->id);
+ iowrite32(val, chan->chip->apb_regs + offset);
+ }
+ }
+
reg |= (chan->config.device_fc ?
DWAXIDMAC_TT_FC_MEM_TO_PER_DST :
DWAXIDMAC_TT_FC_MEM_TO_PER_DMAC)
@@ -994,8 +1013,9 @@ static int dma_chan_terminate_all(struct dma_chan *dchan)
{
struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
u32 chan_active = BIT(chan->id) << DMAC_CHAN_EN_SHIFT;
+ u32 reg_width = __ffs(chan->config.dst_addr_width);
unsigned long flags;
- u32 val;
+ u32 offset, val;
int ret;
LIST_HEAD(head);
@@ -1007,9 +1027,23 @@ static int dma_chan_terminate_all(struct dma_chan *dchan)
dev_warn(dchan2dev(dchan),
"%s failed to stop\n", axi_chan_name(chan));
- if (chan->direction != DMA_MEM_TO_MEM)
- dw_axi_dma_set_hw_channel(chan->chip,
- chan->hw_handshake_num, false);
+ if (chan->direction != DMA_MEM_TO_MEM) {
+ ret = dw_axi_dma_set_hw_channel(chan->chip,
+ chan->hw_handshake_num, false);
+ if (ret == 0 && chan->direction == DMA_MEM_TO_DEV) {
+ if (reg_width == DWAXIDMAC_TRANS_WIDTH_8) {
+ offset = DMAC_APB_BYTE_WR_CH_EN;
+ val = ioread32(chan->chip->apb_regs + offset);
+ val &= ~BIT(chan->id);
+ iowrite32(val, chan->chip->apb_regs + offset);
+ } else if (reg_width == DWAXIDMAC_TRANS_WIDTH_16) {
+ offset = DMAC_APB_HALFWORD_WR_CH_EN;
+ val = ioread32(chan->chip->apb_regs + offset);
+ val &= ~BIT(chan->id);
+ iowrite32(val, chan->chip->apb_regs + offset);
+ }
+ }
+ }
spin_lock_irqsave(&chan->vc.lock, flags);
--
2.18.0
Hi Sia Jee Heng,
see my comments inlined:
> From: Sia Jee Heng <[email protected]>
> Sent: Tuesday, December 29, 2020 07:47
> To: [email protected]; Eugeniy Paltsev; [email protected]
> Cc: [email protected]; [email protected]; [email protected]; [email protected]
> Subject: [PATCH v8 13/16] dmaengine: dw-axi-dmac: Add Intel KeemBay AxiDMA handshake
>
> Add support for Intel KeemBay AxiDMA device handshake programming.
> Device handshake number passed in to the AxiDMA shall be written to
> the Intel KeemBay AxiDMA hardware handshake registers before DMA
> operations are started.
>
> Reviewed-by: Andy Shevchenko <[email protected]>
> Signed-off-by: Sia Jee Heng <[email protected]>
> ---
> .../dma/dw-axi-dmac/dw-axi-dmac-platform.c | 52 +++++++++++++++++++
> 1 file changed, 52 insertions(+)
>
> diff --git a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
> index 062d27c61983..5e77eb3d040f 100644
> --- a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
> +++ b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
[snip]
> +
> + return 0;
> +}
> +
> /*
> * If DW_axi_dmac sees CHx_CTL.ShadowReg_Or_LLI_Last bit of the fetched LLI
> * as 1, it understands that the current block is the final block in the
> @@ -626,6 +668,9 @@ dw_axi_dma_chan_prep_cyclic(struct dma_chan *dchan, dma_addr_t dma_addr,
> llp = hw_desc->llp;
> } while (num_periods);
>
> + if (dw_axi_dma_set_hw_channel(chan->chip, chan->hw_handshake_num, true))
> + goto err_desc_get;
> +
In this implementation 'dw_axi_dma_chan_prep_cyclic' callback will fail if
we don't have APB registers which are only specific for KeemBay.
Looking for the code of 'dw_axi_dma_chan_prep_cyclic' I don't see the reason
why it shouldn't work for vanila DW AXI DMAC without this extension. So, could
you please change this so we wouldn't reject dw_axi_dma_chan_prep_cyclic in case
of APB registers are missed.
> return vchan_tx_prep(&chan->vc, &desc->vd, flags);
>
> err_desc_get:
> @@ -684,6 +729,9 @@ dw_axi_dma_chan_prep_slave_sg(struct dma_chan *dchan, struct scatterlist *sgl,
> llp = hw_desc->llp;
> } while (sg_len);
>
> + if (dw_axi_dma_set_hw_channel(chan->chip, chan->hw_handshake_num, true))
> + goto err_desc_get;
> +
Same here.
> return vchan_tx_prep(&chan->vc, &desc->vd, flags);
>
> err_desc_get:
> @@ -959,6 +1007,10 @@ static int dma_chan_terminate_all(struct dma_chan *dchan)
> dev_warn(dchan2dev(dchan),
> "%s failed to stop\n", axi_chan_name(chan));
>
> + if (chan->direction != DMA_MEM_TO_MEM)
> + dw_axi_dma_set_hw_channel(chan->chip,
> + chan->hw_handshake_num, false);
> +
> spin_lock_irqsave(&chan->vc.lock, flags);
>
> vchan_get_all_descriptors(&chan->vc, &head);
> --
> 2.18.0
>
> -----Original Message-----
> From: Eugeniy Paltsev <[email protected]>
> Sent: 31 December 2020 8:44 PM
> To: Sia, Jee Heng <[email protected]>; Vinod Koul
> <[email protected]>
> Cc: [email protected]; [email protected];
> [email protected]; [email protected];
> [email protected]
> Subject: Re: [PATCH v8 13/16] dmaengine: dw-axi-dmac: Add Intel
> KeemBay AxiDMA handshake
>
> Hi Sia Jee Heng,
>
> see my comments inlined:
>
> > From: Sia Jee Heng <[email protected]>
> > Sent: Tuesday, December 29, 2020 07:47
> > To: [email protected]; Eugeniy Paltsev; [email protected]
> > Cc: [email protected];
> [email protected];
> > [email protected]; [email protected]
> > Subject: [PATCH v8 13/16] dmaengine: dw-axi-dmac: Add Intel
> KeemBay
> > AxiDMA handshake
> >
> > Add support for Intel KeemBay AxiDMA device handshake
> programming.
> > Device handshake number passed in to the AxiDMA shall be written
> to
> > the Intel KeemBay AxiDMA hardware handshake registers before
> DMA
> > operations are started.
> >
> > Reviewed-by: Andy Shevchenko
> <[email protected]>
> > Signed-off-by: Sia Jee Heng <[email protected]>
> > ---
> > .../dma/dw-axi-dmac/dw-axi-dmac-platform.c | 52
> +++++++++++++++++++
> > 1 file changed, 52 insertions(+)
> >
> > diff --git a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
> > b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
> > index 062d27c61983..5e77eb3d040f 100644
> > --- a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
> > +++ b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
> [snip]
> > +
> > + return 0;
> > +}
> > +
> > /*
> > * If DW_axi_dmac sees CHx_CTL.ShadowReg_Or_LLI_Last bit of
> the fetched LLI
> > * as 1, it understands that the current block is the final block in
> > the @@ -626,6 +668,9 @@ dw_axi_dma_chan_prep_cyclic(struct
> dma_chan *dchan, dma_addr_t dma_addr,
> > llp = hw_desc->llp;
> > } while (num_periods);
> >
> > + if (dw_axi_dma_set_hw_channel(chan->chip, chan-
> >hw_handshake_num, true))
> > + goto err_desc_get;
> > +
>
> In this implementation 'dw_axi_dma_chan_prep_cyclic' callback will
> fail if we don't have APB registers which are only specific for KeemBay.
> Looking for the code of 'dw_axi_dma_chan_prep_cyclic' I don't see
> the reason why it shouldn't work for vanila DW AXI DMAC without this
> extension. So, could you please change this so we wouldn't reject
> dw_axi_dma_chan_prep_cyclic in case of APB registers are missed.
[>>] OK, I can change the code in such a way that dw_axi_dma_set_hw_channel() will be executed only if apb_reg is valid.
>
> > return vchan_tx_prep(&chan->vc, &desc->vd, flags);
> >
> > err_desc_get:
> > @@ -684,6 +729,9 @@ dw_axi_dma_chan_prep_slave_sg(struct
> dma_chan *dchan, struct scatterlist *sgl,
> > llp = hw_desc->llp;
> > } while (sg_len);
> >
> > + if (dw_axi_dma_set_hw_channel(chan->chip, chan-
> >hw_handshake_num, true))
> > + goto err_desc_get;
> > +
>
> Same here.
[>>] Sure, same method described above will be used.
>
>
> > return vchan_tx_prep(&chan->vc, &desc->vd, flags);
> >
> > err_desc_get:
> > @@ -959,6 +1007,10 @@ static int dma_chan_terminate_all(struct
> dma_chan *dchan)
> > dev_warn(dchan2dev(dchan),
> > "%s failed to stop\n", axi_chan_name(chan));
> >
> > + if (chan->direction != DMA_MEM_TO_MEM)
> > + dw_axi_dma_set_hw_channel(chan->chip,
> > + chan->hw_handshake_num,
> > + false);
> > +
> > spin_lock_irqsave(&chan->vc.lock, flags);
> >
> > vchan_get_all_descriptors(&chan->vc, &head);
> > --
> > 2.18.0
> >