2024-02-16 17:35:25

by Manivannan Sadhasivam

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

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 <[email protected]>
Signed-off-by: Manivannan Sadhasivam <[email protected]>
---
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



2024-02-20 12:12:11

by Siddharth Vadapalli

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

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 <[email protected]>
> Signed-off-by: Manivannan Sadhasivam <[email protected]>
> ---
> 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.

2024-02-21 05:35:18

by Manivannan Sadhasivam

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

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 <[email protected]>
> > Signed-off-by: Manivannan Sadhasivam <[email protected]>
> > ---
> > 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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