[PATCH v2 0/5] PCI: dwc: Add support for integrating HDMA with DWC EP driver

[PATCH v2 0/5] PCI: dwc: Add support for integrating HDMA with DWC EP driver

[Manivannan Sadhasivam]

Hello,

This series adds support for integrating HDMA with the DWC EP driver.

Hyper DMA (HDMA) is already supported by the dw-edma dmaengine driver.
Unlike it's predecessor Embedded DMA (eDMA), HDMA supports only unroll
mapping format and doesn't support auto detecting the read/write channels.

Hence, this series modifies the existing eDMA code to work with HDMA by
honoring the platform supplied mapping format and read/write channels
count.

The platform drivers making use of HDMA should pass the EDMA_MF_HDMA_NATIVE
flag and provide channels count. In this series, HDMA support is added for
the Qcom SA8775P SoC and the DMA support in enabled in MHI EPF driver as
well.

Testing
-------

Tested on Qualcomm SA8775P Ride board.

Dependency
----------

Depends on:
https://lore.kernel.org/dmaengine/20240129-b4-feature_hdma_mainline-v7-0-8e8c1acb7a46@bootlin.com/
https://lore.kernel.org/all/1701432377-16899-1-git-send-email-quic_msarkar@quicinc.com/

NOTE: I've taken over this series from Mrinmay who posted v1:
https://lore.kernel.org/linux-pci/1705669223-5655-1-git-send-email-quic_msarkar@quicinc.com/

- Mani

Changes in v2:

- Dropped dmaengine patches (Sergey)
- Reworked dw_pcie_edma_find_chip() to support both eDMA and HDMA (Sergey)
- Skipped MF and channel detection if glue drivers have provided them (Sergey)
- Addressed review comments in pcie-qcom-ep and pci-epf-mhi drivers (Mani)

Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
---
Manivannan Sadhasivam (3):
      PCI: dwc: Refactor dw_pcie_edma_find_chip() API
      PCI: dwc: Skip finding eDMA channels count if glue drivers have passed them
      PCI: dwc: Pass the eDMA mapping format flag directly from glue drivers

Mrinmay Sarkar (2):
      PCI: qcom-ep: Add HDMA support for SA8775P SoC
      PCI: epf-mhi: Enable HDMA for SA8775P SoC

 drivers/pci/controller/dwc/pcie-designware.c | 62 +++++++++++++++++++++-------
 drivers/pci/controller/dwc/pcie-designware.h |  5 +--
 drivers/pci/controller/dwc/pcie-qcom-ep.c    | 23 ++++++++++-
 drivers/pci/controller/dwc/pcie-rcar-gen4.c  |  2 +-
 drivers/pci/endpoint/functions/pci-epf-mhi.c |  1 +
 5 files changed, 72 insertions(+), 21 deletions(-)
---
base-commit: fdd10aee7740a53c370a867b8743a8c8945d1db1
change-id: 20240216-dw-hdma-64ddc09fb30b

Best regards,
-- 
Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

[PATCH v2 1/5] PCI: dwc: Refactor dw_pcie_edma_find_chip() API

[Manivannan Sadhasivam]

In order to add support for Hyper DMA (HDMA), let's refactor the existing
dw_pcie_edma_find_chip() API by moving the common code to separate
functions.

No functional change.

Suggested-by: Serge Semin <fancer.lancer@gmail.com>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
---
 drivers/pci/controller/dwc/pcie-designware.c | 40 +++++++++++++++++++++++-----
 1 file changed, 33 insertions(+), 7 deletions(-)

diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c
index 250cf7f40b85..3a26dfc5368f 100644
--- a/drivers/pci/controller/dwc/pcie-designware.c
+++ b/drivers/pci/controller/dwc/pcie-designware.c
@@ -880,7 +880,17 @@ static struct dw_edma_plat_ops dw_pcie_edma_ops = {
 	.irq_vector = dw_pcie_edma_irq_vector,
 };
 
-static int dw_pcie_edma_find_chip(struct dw_pcie *pci)
+static void dw_pcie_edma_init_data(struct dw_pcie *pci)
+{
+	pci->edma.dev = pci->dev;
+
+	if (!pci->edma.ops)
+		pci->edma.ops = &dw_pcie_edma_ops;
+
+	pci->edma.flags |= DW_EDMA_CHIP_LOCAL;
+}
+
+static int dw_pcie_edma_find_mf(struct dw_pcie *pci)
 {
 	u32 val;
 
@@ -902,8 +912,6 @@ static int dw_pcie_edma_find_chip(struct dw_pcie *pci)
 
 	if (val == 0xFFFFFFFF && pci->edma.reg_base) {
 		pci->edma.mf = EDMA_MF_EDMA_UNROLL;
-
-		val = dw_pcie_readl_dma(pci, PCIE_DMA_CTRL);
 	} else if (val != 0xFFFFFFFF) {
 		pci->edma.mf = EDMA_MF_EDMA_LEGACY;
 
@@ -912,12 +920,17 @@ static int dw_pcie_edma_find_chip(struct dw_pcie *pci)
 		return -ENODEV;
 	}
 
-	pci->edma.dev = pci->dev;
+	return 0;
+}
 
-	if (!pci->edma.ops)
-		pci->edma.ops = &dw_pcie_edma_ops;
+static int dw_pcie_edma_find_channels(struct dw_pcie *pci)
+{
+	u32 val;
 
-	pci->edma.flags |= DW_EDMA_CHIP_LOCAL;
+	if (pci->edma.mf == EDMA_MF_EDMA_LEGACY)
+		val = dw_pcie_readl_dbi(pci, PCIE_DMA_VIEWPORT_BASE + PCIE_DMA_CTRL);
+	else
+		val = dw_pcie_readl_dma(pci, PCIE_DMA_CTRL);
 
 	pci->edma.ll_wr_cnt = FIELD_GET(PCIE_DMA_NUM_WR_CHAN, val);
 	pci->edma.ll_rd_cnt = FIELD_GET(PCIE_DMA_NUM_RD_CHAN, val);
@@ -930,6 +943,19 @@ static int dw_pcie_edma_find_chip(struct dw_pcie *pci)
 	return 0;
 }
 
+static int dw_pcie_edma_find_chip(struct dw_pcie *pci)
+{
+	int ret;
+
+	dw_pcie_edma_init_data(pci);
+
+	ret = dw_pcie_edma_find_mf(pci);
+	if (ret)
+		return ret;
+
+	return dw_pcie_edma_find_channels(pci);
+}
+
 static int dw_pcie_edma_irq_verify(struct dw_pcie *pci)
 {
 	struct platform_device *pdev = to_platform_device(pci->dev);

-- 
2.25.1

[PATCH v2 2/5] PCI: dwc: Skip finding eDMA channels count if glue drivers have passed them

[Manivannan Sadhasivam]

In the case of Hyper DMA (HDMA) present in DWC controllers, there is no way
the drivers can auto detect the number of read/write channels as like its
predecessor embedded DMA (eDMA). So the glue drivers making use of HDMA
have to pass the channels count during probe.

To accommodate that, let's skip finding the channels if the channels count
were already passed by glue drivers. If the channels count passed were
wrong in any form, then the existing sanity check will catch it.

Suggested-by: Serge Semin <fancer.lancer@gmail.com>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
---
 drivers/pci/controller/dwc/pcie-designware.c | 16 +++++++++-------
 1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c
index 3a26dfc5368f..d07747b75947 100644
--- a/drivers/pci/controller/dwc/pcie-designware.c
+++ b/drivers/pci/controller/dwc/pcie-designware.c
@@ -927,13 +927,15 @@ static int dw_pcie_edma_find_channels(struct dw_pcie *pci)
 {
 	u32 val;
 
-	if (pci->edma.mf == EDMA_MF_EDMA_LEGACY)
-		val = dw_pcie_readl_dbi(pci, PCIE_DMA_VIEWPORT_BASE + PCIE_DMA_CTRL);
-	else
-		val = dw_pcie_readl_dma(pci, PCIE_DMA_CTRL);
-
-	pci->edma.ll_wr_cnt = FIELD_GET(PCIE_DMA_NUM_WR_CHAN, val);
-	pci->edma.ll_rd_cnt = FIELD_GET(PCIE_DMA_NUM_RD_CHAN, val);
+	if (!pci->edma.ll_wr_cnt || !pci->edma.ll_rd_cnt) {
+		if (pci->edma.mf == EDMA_MF_EDMA_LEGACY)
+			val = dw_pcie_readl_dbi(pci, PCIE_DMA_VIEWPORT_BASE + PCIE_DMA_CTRL);
+		else
+			val = dw_pcie_readl_dma(pci, PCIE_DMA_CTRL);
+
+		pci->edma.ll_wr_cnt = FIELD_GET(PCIE_DMA_NUM_WR_CHAN, val);
+		pci->edma.ll_rd_cnt = FIELD_GET(PCIE_DMA_NUM_RD_CHAN, val);
+	}
 
 	/* Sanity check the channels count if the mapping was incorrect */
 	if (!pci->edma.ll_wr_cnt || pci->edma.ll_wr_cnt > EDMA_MAX_WR_CH ||

-- 
2.25.1

[PATCH v2 3/5] PCI: dwc: Pass the eDMA mapping format flag directly from glue drivers

[Manivannan Sadhasivam]

Instead of maintaining a separate capability for glue drivers that cannot
support auto detection of the eDMA mapping format, let's pass the mapping
format directly from them.

This will simplify the code and also allow adding HDMA support that also
doesn't support auto detection of mapping format.

Suggested-by: Serge Semin <fancer.lancer@gmail.com>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
---
 drivers/pci/controller/dwc/pcie-designware.c | 16 +++++++++-------
 drivers/pci/controller/dwc/pcie-designware.h |  5 ++---
 drivers/pci/controller/dwc/pcie-rcar-gen4.c  |  2 +-
 3 files changed, 12 insertions(+), 11 deletions(-)

diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c
index d07747b75947..54ecd536756d 100644
--- a/drivers/pci/controller/dwc/pcie-designware.c
+++ b/drivers/pci/controller/dwc/pcie-designware.c
@@ -894,18 +894,20 @@ static int dw_pcie_edma_find_mf(struct dw_pcie *pci)
 {
 	u32 val;
 
+	/*
+	 * Bail out finding the mapping format if it is already set by the glue
+	 * driver. Also ensure that the edma.reg_base is pointing to a valid
+	 * memory region.
+	 */
+	if (pci->edma.mf != EDMA_MF_EDMA_LEGACY)
+		return pci->edma.reg_base ? 0 : -ENODEV;
+
 	/*
 	 * Indirect eDMA CSRs access has been completely removed since v5.40a
 	 * thus no space is now reserved for the eDMA channels viewport and
 	 * former DMA CTRL register is no longer fixed to FFs.
-	 *
-	 * Note that Renesas R-Car S4-8's PCIe controllers for unknown reason
-	 * have zeros in the eDMA CTRL register even though the HW-manual
-	 * explicitly states there must FFs if the unrolled mapping is enabled.
-	 * For such cases the low-level drivers are supposed to manually
-	 * activate the unrolled mapping to bypass the auto-detection procedure.
 	 */
-	if (dw_pcie_ver_is_ge(pci, 540A) || dw_pcie_cap_is(pci, EDMA_UNROLL))
+	if (dw_pcie_ver_is_ge(pci, 540A))
 		val = 0xFFFFFFFF;
 	else
 		val = dw_pcie_readl_dbi(pci, PCIE_DMA_VIEWPORT_BASE + PCIE_DMA_CTRL);
diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h
index 26dae4837462..995805279021 100644
--- a/drivers/pci/controller/dwc/pcie-designware.h
+++ b/drivers/pci/controller/dwc/pcie-designware.h
@@ -51,9 +51,8 @@
 
 /* DWC PCIe controller capabilities */
 #define DW_PCIE_CAP_REQ_RES		0
-#define DW_PCIE_CAP_EDMA_UNROLL		1
-#define DW_PCIE_CAP_IATU_UNROLL		2
-#define DW_PCIE_CAP_CDM_CHECK		3
+#define DW_PCIE_CAP_IATU_UNROLL		1
+#define DW_PCIE_CAP_CDM_CHECK		2
 
 #define dw_pcie_cap_is(_pci, _cap) \
 	test_bit(DW_PCIE_CAP_ ## _cap, &(_pci)->caps)
diff --git a/drivers/pci/controller/dwc/pcie-rcar-gen4.c b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
index e9166619b1f9..3c535ef5ea91 100644
--- a/drivers/pci/controller/dwc/pcie-rcar-gen4.c
+++ b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
@@ -255,7 +255,7 @@ static struct rcar_gen4_pcie *rcar_gen4_pcie_alloc(struct platform_device *pdev)
 	rcar->dw.ops = &dw_pcie_ops;
 	rcar->dw.dev = dev;
 	rcar->pdev = pdev;
-	dw_pcie_cap_set(&rcar->dw, EDMA_UNROLL);
+	rcar->dw.edma.mf = EDMA_MF_EDMA_UNROLL;
 	dw_pcie_cap_set(&rcar->dw, REQ_RES);
 	platform_set_drvdata(pdev, rcar);
 

-- 
2.25.1

[PATCH v2 4/5] PCI: qcom-ep: Add HDMA support for SA8775P SoC

[Manivannan Sadhasivam]

From: Mrinmay Sarkar <quic_msarkar@quicinc.com>

SA8775P SoC supports the new Hyper DMA (HDMA) DMA Engine inside the DWC IP.
Let's add support for it by passing the mapping format and the number of
read/write channels count.

The PCIe EP controller used on this SoC is of version 1.34.0, so a separate
config struct is introduced for the sake of enabling HDMA conditionally.

It should be noted that for the eDMA support (predecessor of HDMA), there
are no mapping format and channels count specified. That is because eDMA
supports auto detection of both parameters, whereas HDMA doesn't.

Signed-off-by: Mrinmay Sarkar <quic_msarkar@quicinc.com>
[mani: Reworded commit message, added kdoc, and minor cleanups]
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
---
 drivers/pci/controller/dwc/pcie-qcom-ep.c | 23 ++++++++++++++++++++++-
 1 file changed, 22 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/controller/dwc/pcie-qcom-ep.c b/drivers/pci/controller/dwc/pcie-qcom-ep.c
index 45008e054e31..89d06a3e6e06 100644
--- a/drivers/pci/controller/dwc/pcie-qcom-ep.c
+++ b/drivers/pci/controller/dwc/pcie-qcom-ep.c
@@ -149,6 +149,14 @@ enum qcom_pcie_ep_link_status {
 	QCOM_PCIE_EP_LINK_DOWN,
 };
 
+/**
+ * struct qcom_pcie_ep_cfg - Per SoC config struct
+ * @hdma_support: HDMA support on this SoC
+ */
+struct qcom_pcie_ep_cfg {
+	bool hdma_support;
+};
+
 /**
  * struct qcom_pcie_ep - Qualcomm PCIe Endpoint Controller
  * @pci: Designware PCIe controller struct
@@ -803,6 +811,7 @@ static const struct dw_pcie_ep_ops pci_ep_ops = {
 
 static int qcom_pcie_ep_probe(struct platform_device *pdev)
 {
+	const struct qcom_pcie_ep_cfg *cfg;
 	struct device *dev = &pdev->dev;
 	struct qcom_pcie_ep *pcie_ep;
 	char *name;
@@ -816,6 +825,14 @@ static int qcom_pcie_ep_probe(struct platform_device *pdev)
 	pcie_ep->pci.ops = &pci_ops;
 	pcie_ep->pci.ep.ops = &pci_ep_ops;
 	pcie_ep->pci.edma.nr_irqs = 1;
+
+	cfg = of_device_get_match_data(dev);
+	if (cfg && cfg->hdma_support) {
+		pcie_ep->pci.edma.ll_wr_cnt = 8;
+		pcie_ep->pci.edma.ll_rd_cnt = 8;
+		pcie_ep->pci.edma.mf = EDMA_MF_HDMA_NATIVE;
+	}
+
 	platform_set_drvdata(pdev, pcie_ep);
 
 	ret = qcom_pcie_ep_get_resources(pdev, pcie_ep);
@@ -874,8 +891,12 @@ static void qcom_pcie_ep_remove(struct platform_device *pdev)
 	qcom_pcie_disable_resources(pcie_ep);
 }
 
+static const struct qcom_pcie_ep_cfg cfg_1_34_0 = {
+	.hdma_support = true,
+};
+
 static const struct of_device_id qcom_pcie_ep_match[] = {
-	{ .compatible = "qcom,sa8775p-pcie-ep", },
+	{ .compatible = "qcom,sa8775p-pcie-ep", .data = &cfg_1_34_0},
 	{ .compatible = "qcom,sdx55-pcie-ep", },
 	{ .compatible = "qcom,sm8450-pcie-ep", },
 	{ }

-- 
2.25.1

[PATCH v2 5/5] PCI: epf-mhi: Enable HDMA for SA8775P SoC

[Manivannan Sadhasivam]

From: Mrinmay Sarkar <quic_msarkar@quicinc.com>

SA8775P SoC supports Hyper DMA (HDMA) DMA Engine present in the DWC IP. So,
let's enable it in the EPF driver so that the DMA Engine APIs can be used
for data transfer.

Signed-off-by: Mrinmay Sarkar <quic_msarkar@quicinc.com>
[mani: reworded commit message]
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
---
 drivers/pci/endpoint/functions/pci-epf-mhi.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/pci/endpoint/functions/pci-epf-mhi.c b/drivers/pci/endpoint/functions/pci-epf-mhi.c
index 2c54d80107cf..570c1d1fb12e 100644
--- a/drivers/pci/endpoint/functions/pci-epf-mhi.c
+++ b/drivers/pci/endpoint/functions/pci-epf-mhi.c
@@ -137,6 +137,7 @@ static const struct pci_epf_mhi_ep_info sa8775p_info = {
 	.epf_flags = PCI_BASE_ADDRESS_MEM_TYPE_32,
 	.msi_count = 32,
 	.mru = 0x8000,
+	.flags = MHI_EPF_USE_DMA,
 };
 
 struct pci_epf_mhi {

-- 
2.25.1

Re: [PATCH v2 1/5] PCI: dwc: Refactor dw_pcie_edma_find_chip() API

[Siddharth Vadapalli]

On 24/02/16 11:04PM, Manivannan Sadhasivam wrote:
> In order to add support for Hyper DMA (HDMA), let's refactor the existing
> dw_pcie_edma_find_chip() API by moving the common code to separate
> functions.
> 
> No functional change.
> 
> Suggested-by: Serge Semin <fancer.lancer@gmail.com>
> Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
> ---
>  drivers/pci/controller/dwc/pcie-designware.c | 40 +++++++++++++++++++++++-----
>  1 file changed, 33 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c
> index 250cf7f40b85..3a26dfc5368f 100644
> --- a/drivers/pci/controller/dwc/pcie-designware.c
> +++ b/drivers/pci/controller/dwc/pcie-designware.c
> @@ -880,7 +880,17 @@ static struct dw_edma_plat_ops dw_pcie_edma_ops = {
>  	.irq_vector = dw_pcie_edma_irq_vector,
>  };
>  
> -static int dw_pcie_edma_find_chip(struct dw_pcie *pci)
> +static void dw_pcie_edma_init_data(struct dw_pcie *pci)
> +{
> +	pci->edma.dev = pci->dev;
> +
> +	if (!pci->edma.ops)
> +		pci->edma.ops = &dw_pcie_edma_ops;
> +
> +	pci->edma.flags |= DW_EDMA_CHIP_LOCAL;
> +}
> +
> +static int dw_pcie_edma_find_mf(struct dw_pcie *pci)
>  {
>  	u32 val;
>  
> @@ -902,8 +912,6 @@ static int dw_pcie_edma_find_chip(struct dw_pcie *pci)
>  
>  	if (val == 0xFFFFFFFF && pci->edma.reg_base) {
>  		pci->edma.mf = EDMA_MF_EDMA_UNROLL;
> -
> -		val = dw_pcie_readl_dma(pci, PCIE_DMA_CTRL);
>  	} else if (val != 0xFFFFFFFF) {
>  		pci->edma.mf = EDMA_MF_EDMA_LEGACY;

Minor suggestion:

The above section prior to this patch was:
	if (val == 0xFFFFFFFF && pci->edma.reg_base) {
		pci->edma.mf = EDMA_MF_EDMA_UNROLL;

		val = dw_pcie_readl_dma(pci, PCIE_DMA_CTRL);
	} else if (val != 0xFFFFFFFF) {
		pci->edma.mf = EDMA_MF_EDMA_LEGACY;

		pci->edma.reg_base = pci->dbi_base + PCIE_DMA_VIEWPORT_BASE;
	} else {
		return -ENODEV;
	}

And this patch is removing the call to dw_pcie_readl_dma() in the "if"
condition above. So the curly braces after this patch will only be
present because of the "else if" statement. So is the following change a
good idea?

	/* Assume it is EDMA_LEGACY by default but update it later if needed */
	pci->edma.mf = EDMA_MF_EDMA_LEGACY;

	if (val == 0xFFFFFFFF && pci->edma.reg_base)
		pci->edma.mf = EDMA_MF_EDMA_UNROLL;
	else if (val != 0xFFFFFFFF)
		pci->edma.reg_base = pci->dbi_base + PCIE_DMA_VIEWPORT_BASE;
	else
		return -ENODEV;


Regards,
Siddharth.

Re: [PATCH v2 2/5] PCI: dwc: Skip finding eDMA channels count if glue drivers have passed them

[Siddharth Vadapalli]

On 24/02/16 11:04PM, Manivannan Sadhasivam wrote:
> In the case of Hyper DMA (HDMA) present in DWC controllers, there is no way
> the drivers can auto detect the number of read/write channels as like its
> predecessor embedded DMA (eDMA). So the glue drivers making use of HDMA
> have to pass the channels count during probe.
> 
> To accommodate that, let's skip finding the channels if the channels count
> were already passed by glue drivers. If the channels count passed were
> wrong in any form, then the existing sanity check will catch it.
> 
> Suggested-by: Serge Semin <fancer.lancer@gmail.com>
> Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

Reviewed-by: Siddharth Vadapalli <s-vadapalli@ti.com>

Regards,
Siddharth.
> ---
>  drivers/pci/controller/dwc/pcie-designware.c | 16 +++++++++-------
>  1 file changed, 9 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c
> index 3a26dfc5368f..d07747b75947 100644
> --- a/drivers/pci/controller/dwc/pcie-designware.c
> +++ b/drivers/pci/controller/dwc/pcie-designware.c
> @@ -927,13 +927,15 @@ static int dw_pcie_edma_find_channels(struct dw_pcie *pci)
>  {
>  	u32 val;
>  
> -	if (pci->edma.mf == EDMA_MF_EDMA_LEGACY)
> -		val = dw_pcie_readl_dbi(pci, PCIE_DMA_VIEWPORT_BASE + PCIE_DMA_CTRL);
> -	else
> -		val = dw_pcie_readl_dma(pci, PCIE_DMA_CTRL);
> -
> -	pci->edma.ll_wr_cnt = FIELD_GET(PCIE_DMA_NUM_WR_CHAN, val);
> -	pci->edma.ll_rd_cnt = FIELD_GET(PCIE_DMA_NUM_RD_CHAN, val);
> +	if (!pci->edma.ll_wr_cnt || !pci->edma.ll_rd_cnt) {
> +		if (pci->edma.mf == EDMA_MF_EDMA_LEGACY)
> +			val = dw_pcie_readl_dbi(pci, PCIE_DMA_VIEWPORT_BASE + PCIE_DMA_CTRL);
> +		else
> +			val = dw_pcie_readl_dma(pci, PCIE_DMA_CTRL);
> +
> +		pci->edma.ll_wr_cnt = FIELD_GET(PCIE_DMA_NUM_WR_CHAN, val);
> +		pci->edma.ll_rd_cnt = FIELD_GET(PCIE_DMA_NUM_RD_CHAN, val);
> +	}
>  
>  	/* Sanity check the channels count if the mapping was incorrect */
>  	if (!pci->edma.ll_wr_cnt || pci->edma.ll_wr_cnt > EDMA_MAX_WR_CH ||
> 
> -- 
> 2.25.1
> 
> 

Re: [PATCH v2 3/5] PCI: dwc: Pass the eDMA mapping format flag directly from glue drivers

[Siddharth Vadapalli]

On 24/02/16 11:04PM, Manivannan Sadhasivam wrote:
> Instead of maintaining a separate capability for glue drivers that cannot
> support auto detection of the eDMA mapping format, let's pass the mapping
> format directly from them.
> 
> This will simplify the code and also allow adding HDMA support that also
> doesn't support auto detection of mapping format.
> 
> Suggested-by: Serge Semin <fancer.lancer@gmail.com>
> Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

Reviewed-by: Siddharth Vadapalli <s-vadapalli@ti.com>

Regards,
Siddharth.
> ---
>  drivers/pci/controller/dwc/pcie-designware.c | 16 +++++++++-------
>  drivers/pci/controller/dwc/pcie-designware.h |  5 ++---
>  drivers/pci/controller/dwc/pcie-rcar-gen4.c  |  2 +-
>  3 files changed, 12 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c
> index d07747b75947..54ecd536756d 100644
> --- a/drivers/pci/controller/dwc/pcie-designware.c
> +++ b/drivers/pci/controller/dwc/pcie-designware.c
> @@ -894,18 +894,20 @@ static int dw_pcie_edma_find_mf(struct dw_pcie *pci)
>  {
>  	u32 val;
>  
> +	/*
> +	 * Bail out finding the mapping format if it is already set by the glue
> +	 * driver. Also ensure that the edma.reg_base is pointing to a valid
> +	 * memory region.
> +	 */
> +	if (pci->edma.mf != EDMA_MF_EDMA_LEGACY)
> +		return pci->edma.reg_base ? 0 : -ENODEV;
> +
>  	/*
>  	 * Indirect eDMA CSRs access has been completely removed since v5.40a
>  	 * thus no space is now reserved for the eDMA channels viewport and
>  	 * former DMA CTRL register is no longer fixed to FFs.
> -	 *
> -	 * Note that Renesas R-Car S4-8's PCIe controllers for unknown reason
> -	 * have zeros in the eDMA CTRL register even though the HW-manual
> -	 * explicitly states there must FFs if the unrolled mapping is enabled.
> -	 * For such cases the low-level drivers are supposed to manually
> -	 * activate the unrolled mapping to bypass the auto-detection procedure.
>  	 */
> -	if (dw_pcie_ver_is_ge(pci, 540A) || dw_pcie_cap_is(pci, EDMA_UNROLL))
> +	if (dw_pcie_ver_is_ge(pci, 540A))
>  		val = 0xFFFFFFFF;
>  	else
>  		val = dw_pcie_readl_dbi(pci, PCIE_DMA_VIEWPORT_BASE + PCIE_DMA_CTRL);
> diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h
> index 26dae4837462..995805279021 100644
> --- a/drivers/pci/controller/dwc/pcie-designware.h
> +++ b/drivers/pci/controller/dwc/pcie-designware.h
> @@ -51,9 +51,8 @@
>  
>  /* DWC PCIe controller capabilities */
>  #define DW_PCIE_CAP_REQ_RES		0
> -#define DW_PCIE_CAP_EDMA_UNROLL		1
> -#define DW_PCIE_CAP_IATU_UNROLL		2
> -#define DW_PCIE_CAP_CDM_CHECK		3
> +#define DW_PCIE_CAP_IATU_UNROLL		1
> +#define DW_PCIE_CAP_CDM_CHECK		2
>  
>  #define dw_pcie_cap_is(_pci, _cap) \
>  	test_bit(DW_PCIE_CAP_ ## _cap, &(_pci)->caps)
> diff --git a/drivers/pci/controller/dwc/pcie-rcar-gen4.c b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> index e9166619b1f9..3c535ef5ea91 100644
> --- a/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> +++ b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> @@ -255,7 +255,7 @@ static struct rcar_gen4_pcie *rcar_gen4_pcie_alloc(struct platform_device *pdev)
>  	rcar->dw.ops = &dw_pcie_ops;
>  	rcar->dw.dev = dev;
>  	rcar->pdev = pdev;
> -	dw_pcie_cap_set(&rcar->dw, EDMA_UNROLL);
> +	rcar->dw.edma.mf = EDMA_MF_EDMA_UNROLL;
>  	dw_pcie_cap_set(&rcar->dw, REQ_RES);
>  	platform_set_drvdata(pdev, rcar);
>  
> 
> -- 
> 2.25.1
> 
> 

Re: [PATCH v2 4/5] PCI: qcom-ep: Add HDMA support for SA8775P SoC

[Siddharth Vadapalli]

On 24/02/16 11:04PM, Manivannan Sadhasivam wrote:
> From: Mrinmay Sarkar <quic_msarkar@quicinc.com>
> 
> SA8775P SoC supports the new Hyper DMA (HDMA) DMA Engine inside the DWC IP.
> Let's add support for it by passing the mapping format and the number of
> read/write channels count.
> 
> The PCIe EP controller used on this SoC is of version 1.34.0, so a separate
> config struct is introduced for the sake of enabling HDMA conditionally.
> 
> It should be noted that for the eDMA support (predecessor of HDMA), there
> are no mapping format and channels count specified. That is because eDMA
> supports auto detection of both parameters, whereas HDMA doesn't.
> 
> Signed-off-by: Mrinmay Sarkar <quic_msarkar@quicinc.com>
> [mani: Reworded commit message, added kdoc, and minor cleanups]
> Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

Reviewed-by: Siddharth Vadapalli <s-vadapalli@ti.com>

Regards,
Siddharth.
> ---
>  drivers/pci/controller/dwc/pcie-qcom-ep.c | 23 ++++++++++++++++++++++-
>  1 file changed, 22 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/pci/controller/dwc/pcie-qcom-ep.c b/drivers/pci/controller/dwc/pcie-qcom-ep.c
> index 45008e054e31..89d06a3e6e06 100644
> --- a/drivers/pci/controller/dwc/pcie-qcom-ep.c
> +++ b/drivers/pci/controller/dwc/pcie-qcom-ep.c
> @@ -149,6 +149,14 @@ enum qcom_pcie_ep_link_status {
>  	QCOM_PCIE_EP_LINK_DOWN,
>  };
>  
> +/**
> + * struct qcom_pcie_ep_cfg - Per SoC config struct
> + * @hdma_support: HDMA support on this SoC
> + */
> +struct qcom_pcie_ep_cfg {
> +	bool hdma_support;
> +};
> +
>  /**
>   * struct qcom_pcie_ep - Qualcomm PCIe Endpoint Controller
>   * @pci: Designware PCIe controller struct
> @@ -803,6 +811,7 @@ static const struct dw_pcie_ep_ops pci_ep_ops = {
>  
>  static int qcom_pcie_ep_probe(struct platform_device *pdev)
>  {
> +	const struct qcom_pcie_ep_cfg *cfg;
>  	struct device *dev = &pdev->dev;
>  	struct qcom_pcie_ep *pcie_ep;
>  	char *name;
> @@ -816,6 +825,14 @@ static int qcom_pcie_ep_probe(struct platform_device *pdev)
>  	pcie_ep->pci.ops = &pci_ops;
>  	pcie_ep->pci.ep.ops = &pci_ep_ops;
>  	pcie_ep->pci.edma.nr_irqs = 1;
> +
> +	cfg = of_device_get_match_data(dev);
> +	if (cfg && cfg->hdma_support) {
> +		pcie_ep->pci.edma.ll_wr_cnt = 8;
> +		pcie_ep->pci.edma.ll_rd_cnt = 8;
> +		pcie_ep->pci.edma.mf = EDMA_MF_HDMA_NATIVE;
> +	}
> +
>  	platform_set_drvdata(pdev, pcie_ep);
>  
>  	ret = qcom_pcie_ep_get_resources(pdev, pcie_ep);
> @@ -874,8 +891,12 @@ static void qcom_pcie_ep_remove(struct platform_device *pdev)
>  	qcom_pcie_disable_resources(pcie_ep);
>  }
>  
> +static const struct qcom_pcie_ep_cfg cfg_1_34_0 = {
> +	.hdma_support = true,
> +};
> +
>  static const struct of_device_id qcom_pcie_ep_match[] = {
> -	{ .compatible = "qcom,sa8775p-pcie-ep", },
> +	{ .compatible = "qcom,sa8775p-pcie-ep", .data = &cfg_1_34_0},
>  	{ .compatible = "qcom,sdx55-pcie-ep", },
>  	{ .compatible = "qcom,sm8450-pcie-ep", },
>  	{ }
> 
> -- 
> 2.25.1
> 
> 

Re: [PATCH v2 5/5] PCI: epf-mhi: Enable HDMA for SA8775P SoC

[Siddharth Vadapalli]

On 24/02/16 11:04PM, Manivannan Sadhasivam wrote:
> From: Mrinmay Sarkar <quic_msarkar@quicinc.com>
> 
> SA8775P SoC supports Hyper DMA (HDMA) DMA Engine present in the DWC IP. So,
> let's enable it in the EPF driver so that the DMA Engine APIs can be used
> for data transfer.
> 
> Signed-off-by: Mrinmay Sarkar <quic_msarkar@quicinc.com>
> [mani: reworded commit message]
> Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

Reviewed-by: Siddharth Vadapalli <s-vadapalli@ti.com>

Regards,
Siddharth.
> ---
>  drivers/pci/endpoint/functions/pci-epf-mhi.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/pci/endpoint/functions/pci-epf-mhi.c b/drivers/pci/endpoint/functions/pci-epf-mhi.c
> index 2c54d80107cf..570c1d1fb12e 100644
> --- a/drivers/pci/endpoint/functions/pci-epf-mhi.c
> +++ b/drivers/pci/endpoint/functions/pci-epf-mhi.c
> @@ -137,6 +137,7 @@ static const struct pci_epf_mhi_ep_info sa8775p_info = {
>  	.epf_flags = PCI_BASE_ADDRESS_MEM_TYPE_32,
>  	.msi_count = 32,
>  	.mru = 0x8000,
> +	.flags = MHI_EPF_USE_DMA,
>  };
>  
>  struct pci_epf_mhi {
> 
> -- 
> 2.25.1
> 
> 

Re: [PATCH v2 1/5] PCI: dwc: Refactor dw_pcie_edma_find_chip() API

[Manivannan Sadhasivam]

On Tue, Feb 20, 2024 at 05:41:41PM +0530, Siddharth Vadapalli wrote:
> On 24/02/16 11:04PM, Manivannan Sadhasivam wrote:
> > In order to add support for Hyper DMA (HDMA), let's refactor the existing
> > dw_pcie_edma_find_chip() API by moving the common code to separate
> > functions.
> > 
> > No functional change.
> > 
> > Suggested-by: Serge Semin <fancer.lancer@gmail.com>
> > Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
> > ---
> >  drivers/pci/controller/dwc/pcie-designware.c | 40 +++++++++++++++++++++++-----
> >  1 file changed, 33 insertions(+), 7 deletions(-)
> > 
> > diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c
> > index 250cf7f40b85..3a26dfc5368f 100644
> > --- a/drivers/pci/controller/dwc/pcie-designware.c
> > +++ b/drivers/pci/controller/dwc/pcie-designware.c
> > @@ -880,7 +880,17 @@ static struct dw_edma_plat_ops dw_pcie_edma_ops = {
> >  	.irq_vector = dw_pcie_edma_irq_vector,
> >  };
> >  
> > -static int dw_pcie_edma_find_chip(struct dw_pcie *pci)
> > +static void dw_pcie_edma_init_data(struct dw_pcie *pci)
> > +{
> > +	pci->edma.dev = pci->dev;
> > +
> > +	if (!pci->edma.ops)
> > +		pci->edma.ops = &dw_pcie_edma_ops;
> > +
> > +	pci->edma.flags |= DW_EDMA_CHIP_LOCAL;
> > +}
> > +
> > +static int dw_pcie_edma_find_mf(struct dw_pcie *pci)
> >  {
> >  	u32 val;
> >  
> > @@ -902,8 +912,6 @@ static int dw_pcie_edma_find_chip(struct dw_pcie *pci)
> >  
> >  	if (val == 0xFFFFFFFF && pci->edma.reg_base) {
> >  		pci->edma.mf = EDMA_MF_EDMA_UNROLL;
> > -
> > -		val = dw_pcie_readl_dma(pci, PCIE_DMA_CTRL);
> >  	} else if (val != 0xFFFFFFFF) {
> >  		pci->edma.mf = EDMA_MF_EDMA_LEGACY;
> 
> Minor suggestion:
> 
> The above section prior to this patch was:
> 	if (val == 0xFFFFFFFF && pci->edma.reg_base) {
> 		pci->edma.mf = EDMA_MF_EDMA_UNROLL;
> 
> 		val = dw_pcie_readl_dma(pci, PCIE_DMA_CTRL);
> 	} else if (val != 0xFFFFFFFF) {
> 		pci->edma.mf = EDMA_MF_EDMA_LEGACY;
> 
> 		pci->edma.reg_base = pci->dbi_base + PCIE_DMA_VIEWPORT_BASE;
> 	} else {
> 		return -ENODEV;
> 	}
> 
> And this patch is removing the call to dw_pcie_readl_dma() in the "if"
> condition above. So the curly braces after this patch will only be
> present because of the "else if" statement. So is the following change a
> good idea?
> 

Yes indeed. Actually, EDMA_MF_EDMA_LEGACY is the default mapping format (because
its value is 0x0), but setting it explicitly would also make sense.

- Mani

-- 
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