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

Devi Priya
2023-06-23T04:58:02Z

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(+)

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);

--
2.17.1