diff mbox series

PCI: qcom: configure the parf halt window size to 1GB

Message ID 20230623045731.29397-1-quic_devipriy@quicinc.com
State New
Headers show
Series PCI: qcom: configure the parf halt window size to 1GB | expand

Commit Message

Devi Priya June 23, 2023, 4:57 a.m. UTC 
Configure the ADDR_BIT_INDEX of PARF_AXI_MSTR_WR_ADDR_HALT_V2 register with
0x1E to increase the halt window size to 1GB so that, when new inbound
posted write transactions whose address crosses 1G address range, the
controller would halt all the incoming writes until all the previous AXI
responses are received.

Signed-off-by: Devi Priya <quic_devipriy@quicinc.com>
---
 This patch depends on the below series which adds support for PCIe 
 controllers in IPQ9574
 https://lore.kernel.org/linux-arm-msm/20230519090219.15925-1-quic_devipriy@quicinc.com/

 drivers/pci/controller/dwc/pcie-qcom.c | 9 +++++++++
 1 file changed, 9 insertions(+)

Comments

Devi Priya July 5, 2023, 10:25 a.m. UTC | #1 
On 6/23/2023 3:47 PM, Konrad Dybcio wrote:
> On 23.06.2023 06:57, Devi Priya wrote:
>> Configure the ADDR_BIT_INDEX of PARF_AXI_MSTR_WR_ADDR_HALT_V2 register with
>> 0x1E to increase the halt window size to 1GB so that, when new inbound
>> posted write transactions whose address crosses 1G address range, the
>> controller would halt all the incoming writes until all the previous AXI
>> responses are received.
>>
>> Signed-off-by: Devi Priya <quic_devipriy@quicinc.com>
>> ---
> Has this been tested on anything except IPQ9574? Does it concern other
> SoCs?
This has been tested on IPQ6018 as well.
> 
> 
>>   This patch depends on the below series which adds support for PCIe
>>   controllers in IPQ9574
>>   https://lore.kernel.org/linux-arm-msm/20230519090219.15925-1-quic_devipriy@quicinc.com/
>>
>>   drivers/pci/controller/dwc/pcie-qcom.c | 9 +++++++++
>>   1 file changed, 9 insertions(+)
>>
>> diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
>> index c7579dfa5b1c..26c40e006120 100644
>> --- a/drivers/pci/controller/dwc/pcie-qcom.c
>> +++ b/drivers/pci/controller/dwc/pcie-qcom.c
>> @@ -116,6 +116,8 @@
>>   
>>   /* PARF_AXI_MSTR_WR_ADDR_HALT register fields */
>>   #define EN					BIT(31)
>> +#define ADDR_BIT_INDEX				(BIT(0) | BIT(1) | BIT(2) | \
>> +						BIT(3) | BIT(4) | BIT(5))
> You surely should have the names of these bitfields, mind defining them?
Will use GENMASK(5, 0) as suggested by Mani
> 
>>   
>>   /* PARF_LTSSM register fields */
>>   #define LTSSM_EN				BIT(8)
>> @@ -154,6 +156,8 @@
>>   
>>   #define QCOM_PCIE_CRC8_POLYNOMIAL		(BIT(2) | BIT(1) | BIT(0))
>>   
>> +#define PARF_AXI_MSTR_WR_ADDR_HALT_WINDOW_SIZE	0x1e
>> +
>>   #define QCOM_PCIE_1_0_0_MAX_CLOCKS		4
>>   struct qcom_pcie_resources_1_0_0 {
>>   	struct clk_bulk_data clks[QCOM_PCIE_1_0_0_MAX_CLOCKS];
>> @@ -1126,6 +1130,11 @@ static int qcom_pcie_post_init(struct qcom_pcie *pcie)
>>   
>>   	writel(0, pcie->parf + PARF_Q2A_FLUSH);
>>   
>> +	val = readl(pcie->parf + PARF_AXI_MSTR_WR_ADDR_HALT_V2);
>> +	val &= ~ADDR_BIT_INDEX;
>> +	writel(val | PARF_AXI_MSTR_WR_ADDR_HALT_WINDOW_SIZE, pcie->parf +
>> +			PARF_AXI_MSTR_WR_ADDR_HALT_V2);
> val |= ..
> writel(val, pcie..)
> 
> would be more readable
Okay

Thanks,
Devi Priya
> 
> Konrad
>> +
>>   	dw_pcie_dbi_ro_wr_en(pci);
>>   	writel(PCIE_CAP_SLOT_VAL, pci->dbi_base + offset + PCI_EXP_SLTCAP);
>>
Devi Priya July 5, 2023, 10:27 a.m. UTC | #2 
On 6/24/2023 11:53 AM, Manivannan Sadhasivam wrote:
> On Fri, Jun 23, 2023 at 10:27:31AM +0530, Devi Priya wrote:
>> Configure the ADDR_BIT_INDEX of PARF_AXI_MSTR_WR_ADDR_HALT_V2 register with
>> 0x1E to increase the halt window size to 1GB so that, when new inbound
>> posted write transactions whose address crosses 1G address range, the
>> controller would halt all the incoming writes until all the previous AXI
>> responses are received.
>>
> 
> Can you explain how the value of 0x1e corresponds to 1GB window size?
2^30 (0x1e) = 1G
> 
>> Signed-off-by: Devi Priya <quic_devipriy@quicinc.com>
>> ---
>>   This patch depends on the below series which adds support for PCIe
>>   controllers in IPQ9574
>>   https://lore.kernel.org/linux-arm-msm/20230519090219.15925-1-quic_devipriy@quicinc.com/
>>
>>   drivers/pci/controller/dwc/pcie-qcom.c | 9 +++++++++
>>   1 file changed, 9 insertions(+)
>>
>> diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
>> index c7579dfa5b1c..26c40e006120 100644
>> --- a/drivers/pci/controller/dwc/pcie-qcom.c
>> +++ b/drivers/pci/controller/dwc/pcie-qcom.c
>> @@ -116,6 +116,8 @@
>>   
>>   /* PARF_AXI_MSTR_WR_ADDR_HALT register fields */
>>   #define EN					BIT(31)
>> +#define ADDR_BIT_INDEX				(BIT(0) | BIT(1) | BIT(2) | \
>> +						BIT(3) | BIT(4) | BIT(5))
> 
> GENMASK(5, 0)
okay
> 
>>   
>>   /* PARF_LTSSM register fields */
>>   #define LTSSM_EN				BIT(8)
>> @@ -154,6 +156,8 @@
>>   
>>   #define QCOM_PCIE_CRC8_POLYNOMIAL		(BIT(2) | BIT(1) | BIT(0))
>>   
>> +#define PARF_AXI_MSTR_WR_ADDR_HALT_WINDOW_SIZE	0x1e
> 
> GENMASK(4, 1) as these are address bits.
okay

Thanks,
Devi Priya
> 
> - Mani
> 
>> +
>>   #define QCOM_PCIE_1_0_0_MAX_CLOCKS		4
>>   struct qcom_pcie_resources_1_0_0 {
>>   	struct clk_bulk_data clks[QCOM_PCIE_1_0_0_MAX_CLOCKS];
>> @@ -1126,6 +1130,11 @@ static int qcom_pcie_post_init(struct qcom_pcie *pcie)
>>   
>>   	writel(0, pcie->parf + PARF_Q2A_FLUSH);
>>   
>> +	val = readl(pcie->parf + PARF_AXI_MSTR_WR_ADDR_HALT_V2);
>> +	val &= ~ADDR_BIT_INDEX;
>> +	writel(val | PARF_AXI_MSTR_WR_ADDR_HALT_WINDOW_SIZE, pcie->parf +
>> +			PARF_AXI_MSTR_WR_ADDR_HALT_V2);
>> +
>>   	dw_pcie_dbi_ro_wr_en(pci);
>>   	writel(PCIE_CAP_SLOT_VAL, pci->dbi_base + offset + PCI_EXP_SLTCAP);
>>   
>> -- 
>> 2.17.1
>>
>
Manivannan Sadhasivam July 10, 2023, 3:22 a.m. UTC | #3 
On Wed, Jul 05, 2023 at 03:57:13PM +0530, Devi Priya wrote:
> 
> 
> On 6/24/2023 11:53 AM, Manivannan Sadhasivam wrote:
> > On Fri, Jun 23, 2023 at 10:27:31AM +0530, Devi Priya wrote:
> > > Configure the ADDR_BIT_INDEX of PARF_AXI_MSTR_WR_ADDR_HALT_V2 register with
> > > 0x1E to increase the halt window size to 1GB so that, when new inbound
> > > posted write transactions whose address crosses 1G address range, the
> > > controller would halt all the incoming writes until all the previous AXI
> > > responses are received.
> > > 
> > 
> > Can you explain how the value of 0x1e corresponds to 1GB window size?
> 2^30 (0x1e) = 1G
> > 

So 0x1e selects 2^30 in the hardware? If so, please document it in the commit
message.

- Mani

> > > Signed-off-by: Devi Priya <quic_devipriy@quicinc.com>
> > > ---
> > >   This patch depends on the below series which adds support for PCIe
> > >   controllers in IPQ9574
> > >   https://lore.kernel.org/linux-arm-msm/20230519090219.15925-1-quic_devipriy@quicinc.com/
> > > 
> > >   drivers/pci/controller/dwc/pcie-qcom.c | 9 +++++++++
> > >   1 file changed, 9 insertions(+)
> > > 
> > > diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
> > > index c7579dfa5b1c..26c40e006120 100644
> > > --- a/drivers/pci/controller/dwc/pcie-qcom.c
> > > +++ b/drivers/pci/controller/dwc/pcie-qcom.c
> > > @@ -116,6 +116,8 @@
> > >   /* PARF_AXI_MSTR_WR_ADDR_HALT register fields */
> > >   #define EN					BIT(31)
> > > +#define ADDR_BIT_INDEX				(BIT(0) | BIT(1) | BIT(2) | \
> > > +						BIT(3) | BIT(4) | BIT(5))
> > 
> > GENMASK(5, 0)
> okay
> > 
> > >   /* PARF_LTSSM register fields */
> > >   #define LTSSM_EN				BIT(8)
> > > @@ -154,6 +156,8 @@
> > >   #define QCOM_PCIE_CRC8_POLYNOMIAL		(BIT(2) | BIT(1) | BIT(0))
> > > +#define PARF_AXI_MSTR_WR_ADDR_HALT_WINDOW_SIZE	0x1e
> > 
> > GENMASK(4, 1) as these are address bits.
> okay
> 
> Thanks,
> Devi Priya
> > 
> > - Mani
> > 
> > > +
> > >   #define QCOM_PCIE_1_0_0_MAX_CLOCKS		4
> > >   struct qcom_pcie_resources_1_0_0 {
> > >   	struct clk_bulk_data clks[QCOM_PCIE_1_0_0_MAX_CLOCKS];
> > > @@ -1126,6 +1130,11 @@ static int qcom_pcie_post_init(struct qcom_pcie *pcie)
> > >   	writel(0, pcie->parf + PARF_Q2A_FLUSH);
> > > +	val = readl(pcie->parf + PARF_AXI_MSTR_WR_ADDR_HALT_V2);
> > > +	val &= ~ADDR_BIT_INDEX;
> > > +	writel(val | PARF_AXI_MSTR_WR_ADDR_HALT_WINDOW_SIZE, pcie->parf +
> > > +			PARF_AXI_MSTR_WR_ADDR_HALT_V2);
> > > +
> > >   	dw_pcie_dbi_ro_wr_en(pci);
> > >   	writel(PCIE_CAP_SLOT_VAL, pci->dbi_base + offset + PCI_EXP_SLTCAP);
> > > -- 
> > > 2.17.1
> > > 
> >
diff mbox series

Patch

diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
index c7579dfa5b1c..26c40e006120 100644
--- a/drivers/pci/controller/dwc/pcie-qcom.c
+++ b/drivers/pci/controller/dwc/pcie-qcom.c
@@ -116,6 +116,8 @@ 
 
 /* PARF_AXI_MSTR_WR_ADDR_HALT register fields */
 #define EN					BIT(31)
+#define ADDR_BIT_INDEX				(BIT(0) | BIT(1) | BIT(2) | \
+						BIT(3) | BIT(4) | BIT(5))
 
 /* PARF_LTSSM register fields */
 #define LTSSM_EN				BIT(8)
@@ -154,6 +156,8 @@ 
 
 #define QCOM_PCIE_CRC8_POLYNOMIAL		(BIT(2) | BIT(1) | BIT(0))
 
+#define PARF_AXI_MSTR_WR_ADDR_HALT_WINDOW_SIZE	0x1e
+
 #define QCOM_PCIE_1_0_0_MAX_CLOCKS		4
 struct qcom_pcie_resources_1_0_0 {
 	struct clk_bulk_data clks[QCOM_PCIE_1_0_0_MAX_CLOCKS];
@@ -1126,6 +1130,11 @@  static int qcom_pcie_post_init(struct qcom_pcie *pcie)
 
 	writel(0, pcie->parf + PARF_Q2A_FLUSH);
 
+	val = readl(pcie->parf + PARF_AXI_MSTR_WR_ADDR_HALT_V2);
+	val &= ~ADDR_BIT_INDEX;
+	writel(val | PARF_AXI_MSTR_WR_ADDR_HALT_WINDOW_SIZE, pcie->parf +
+			PARF_AXI_MSTR_WR_ADDR_HALT_V2);
+
 	dw_pcie_dbi_ro_wr_en(pci);
 	writel(PCIE_CAP_SLOT_VAL, pci->dbi_base + offset + PCI_EXP_SLTCAP);