Re: [PATCH v5 5/5] PCI: qcom: Add support for configuring BDF to SID mapping for SM8250
On Tue 27 Oct 12:00 CDT 2020, Manivannan Sadhasivam wrote:
> For SM8250, we need to write the BDF to SID mapping in PCIe controller
> register space for proper working. This is accomplished by extracting
> the BDF and SID values from "iommu-map" property in DT and writing those
> in the register address calculated from the hash value of BDF. In case
> of collisions, the index of the next entry will also be written.
>
> For the sake of it, let's introduce a "config_sid" callback and do it
> conditionally for SM8250.
>
> Signed-off-by: Manivannan Sadhasivam
Reviewed-by: Bjorn Andersson
Regards,
Bjorn
> ---
>
> Rob: I've dropped your review tag as this patch has gone through some
> change (mostly cleanups though)
>
> drivers/pci/controller/dwc/Kconfig | 1 +
> drivers/pci/controller/dwc/pcie-qcom.c | 81 ++
> 2 files changed, 82 insertions(+)
>
> diff --git a/drivers/pci/controller/dwc/Kconfig
> b/drivers/pci/controller/dwc/Kconfig
> index bc049865f8e0..875ebc6e8884 100644
> --- a/drivers/pci/controller/dwc/Kconfig
> +++ b/drivers/pci/controller/dwc/Kconfig
> @@ -169,6 +169,7 @@ config PCIE_QCOM
> depends on OF && (ARCH_QCOM || COMPILE_TEST)
> depends on PCI_MSI_IRQ_DOMAIN
> select PCIE_DW_HOST
> + select CRC8
> help
> Say Y here to enable PCIe controller support on Qualcomm SoCs. The
> PCIe controller uses the DesignWare core plus Qualcomm-specific
> diff --git a/drivers/pci/controller/dwc/pcie-qcom.c
> b/drivers/pci/controller/dwc/pcie-qcom.c
> index 0b180a19b0ea..2148fcf74294 100644
> --- a/drivers/pci/controller/dwc/pcie-qcom.c
> +++ b/drivers/pci/controller/dwc/pcie-qcom.c
> @@ -9,6 +9,7 @@
> */
>
> #include
> +#include
> #include
> #include
> #include
> @@ -57,6 +58,7 @@
> #define PCIE20_PARF_SID_OFFSET 0x234
> #define PCIE20_PARF_BDF_TRANSLATE_CFG0x24C
> #define PCIE20_PARF_DEVICE_TYPE 0x1000
> +#define PCIE20_PARF_BDF_TO_SID_TABLE_N 0x2000
>
> #define PCIE20_ELBI_SYS_CTRL 0x04
> #define PCIE20_ELBI_SYS_CTRL_LT_ENABLE BIT(0)
> @@ -97,6 +99,9 @@
>
> #define QCOM_PCIE_2_1_0_MAX_SUPPLY 3
> #define QCOM_PCIE_2_1_0_MAX_CLOCKS 5
> +
> +#define QCOM_PCIE_CRC8_POLYNOMIAL (BIT(2) | BIT(1) | BIT(0))
> +
> struct qcom_pcie_resources_2_1_0 {
> struct clk_bulk_data clks[QCOM_PCIE_2_1_0_MAX_CLOCKS];
> struct reset_control *pci_reset;
> @@ -179,6 +184,7 @@ struct qcom_pcie_ops {
> void (*deinit)(struct qcom_pcie *pcie);
> void (*post_deinit)(struct qcom_pcie *pcie);
> void (*ltssm_enable)(struct qcom_pcie *pcie);
> + int (*config_sid)(struct qcom_pcie *pcie);
> };
>
> struct qcom_pcie {
> @@ -1261,6 +1267,74 @@ static int qcom_pcie_link_up(struct dw_pcie *pci)
> return !!(val & PCI_EXP_LNKSTA_DLLLA);
> }
>
> +static int qcom_pcie_config_sid_sm8250(struct qcom_pcie *pcie)
> +{
> + /* iommu map structure */
> + struct {
> + u32 bdf;
> + u32 phandle;
> + u32 smmu_sid;
> + u32 smmu_sid_len;
> + } *map;
> + void __iomem *bdf_to_sid_base = pcie->parf +
> PCIE20_PARF_BDF_TO_SID_TABLE_N;
> + struct device *dev = pcie->pci->dev;
> + u8 qcom_pcie_crc8_table[CRC8_TABLE_SIZE];
> + int i, nr_map, size = 0;
> + u32 smmu_sid_base;
> +
> + of_get_property(dev->of_node, "iommu-map", );
> + if (!size)
> + return 0;
> +
> + map = kzalloc(size, GFP_KERNEL);
> + if (!map)
> + return -ENOMEM;
> +
> + of_property_read_u32_array(dev->of_node,
> + "iommu-map", (u32 *)map, size / sizeof(u32));
> +
> + nr_map = size / (sizeof(*map));
> +
> + crc8_populate_msb(qcom_pcie_crc8_table, QCOM_PCIE_CRC8_POLYNOMIAL);
> +
> + /* Registers need to be zero out first */
> + memset_io(bdf_to_sid_base, 0, CRC8_TABLE_SIZE * sizeof(u32));
> +
> + /* Look for an available entry to hold the mapping */
> + for (i = 0; i < nr_map; i++) {
> + u16 bdf_be = cpu_to_be16(map[i].bdf);
> + u32 val;
> + u8 hash;
> +
> + hash = crc8(qcom_pcie_crc8_table, (u8 *)_be, sizeof(bdf_be),
> + 0);
> +
> + val = readl(bdf_to_sid_base + hash * sizeof(u32));
> +
> + /* If the register is already populated, look for next
> available entry */
> + while (val) {
> + u8 current_hash = hash++;
> + u8 next_mask = 0xff;
> +
> + /* If NEXT field is NULL then update it with next hash
> */
> + if (!(val & next_mask)) {
> + val |= (u32)hash;
> + writel(val, bdf_to_sid_base + current_hash *
> sizeof(u32));
> + }
> +
> + val = readl(bdf_to_sid_base + hash * sizeof(u32));
> + }
> +
> +
[PATCH v5 5/5] PCI: qcom: Add support for configuring BDF to SID mapping for SM8250
For SM8250, we need to write the BDF to SID mapping in PCIe controller
register space for proper working. This is accomplished by extracting
the BDF and SID values from "iommu-map" property in DT and writing those
in the register address calculated from the hash value of BDF. In case
of collisions, the index of the next entry will also be written.
For the sake of it, let's introduce a "config_sid" callback and do it
conditionally for SM8250.
Signed-off-by: Manivannan Sadhasivam
---
Rob: I've dropped your review tag as this patch has gone through some
change (mostly cleanups though)
drivers/pci/controller/dwc/Kconfig | 1 +
drivers/pci/controller/dwc/pcie-qcom.c | 81 ++
2 files changed, 82 insertions(+)
diff --git a/drivers/pci/controller/dwc/Kconfig
b/drivers/pci/controller/dwc/Kconfig
index bc049865f8e0..875ebc6e8884 100644
--- a/drivers/pci/controller/dwc/Kconfig
+++ b/drivers/pci/controller/dwc/Kconfig
@@ -169,6 +169,7 @@ config PCIE_QCOM
depends on OF && (ARCH_QCOM || COMPILE_TEST)
depends on PCI_MSI_IRQ_DOMAIN
select PCIE_DW_HOST
+ select CRC8
help
Say Y here to enable PCIe controller support on Qualcomm SoCs. The
PCIe controller uses the DesignWare core plus Qualcomm-specific
diff --git a/drivers/pci/controller/dwc/pcie-qcom.c
b/drivers/pci/controller/dwc/pcie-qcom.c
index 0b180a19b0ea..2148fcf74294 100644
--- a/drivers/pci/controller/dwc/pcie-qcom.c
+++ b/drivers/pci/controller/dwc/pcie-qcom.c
@@ -9,6 +9,7 @@
*/
#include
+#include
#include
#include
#include
@@ -57,6 +58,7 @@
#define PCIE20_PARF_SID_OFFSET 0x234
#define PCIE20_PARF_BDF_TRANSLATE_CFG 0x24C
#define PCIE20_PARF_DEVICE_TYPE0x1000
+#define PCIE20_PARF_BDF_TO_SID_TABLE_N 0x2000
#define PCIE20_ELBI_SYS_CTRL 0x04
#define PCIE20_ELBI_SYS_CTRL_LT_ENABLE BIT(0)
@@ -97,6 +99,9 @@
#define QCOM_PCIE_2_1_0_MAX_SUPPLY 3
#define QCOM_PCIE_2_1_0_MAX_CLOCKS 5
+
+#define QCOM_PCIE_CRC8_POLYNOMIAL (BIT(2) | BIT(1) | BIT(0))
+
struct qcom_pcie_resources_2_1_0 {
struct clk_bulk_data clks[QCOM_PCIE_2_1_0_MAX_CLOCKS];
struct reset_control *pci_reset;
@@ -179,6 +184,7 @@ struct qcom_pcie_ops {
void (*deinit)(struct qcom_pcie *pcie);
void (*post_deinit)(struct qcom_pcie *pcie);
void (*ltssm_enable)(struct qcom_pcie *pcie);
+ int (*config_sid)(struct qcom_pcie *pcie);
};
struct qcom_pcie {
@@ -1261,6 +1267,74 @@ static int qcom_pcie_link_up(struct dw_pcie *pci)
return !!(val & PCI_EXP_LNKSTA_DLLLA);
}
+static int qcom_pcie_config_sid_sm8250(struct qcom_pcie *pcie)
+{
+ /* iommu map structure */
+ struct {
+ u32 bdf;
+ u32 phandle;
+ u32 smmu_sid;
+ u32 smmu_sid_len;
+ } *map;
+ void __iomem *bdf_to_sid_base = pcie->parf +
PCIE20_PARF_BDF_TO_SID_TABLE_N;
+ struct device *dev = pcie->pci->dev;
+ u8 qcom_pcie_crc8_table[CRC8_TABLE_SIZE];
+ int i, nr_map, size = 0;
+ u32 smmu_sid_base;
+
+ of_get_property(dev->of_node, "iommu-map", );
+ if (!size)
+ return 0;
+
+ map = kzalloc(size, GFP_KERNEL);
+ if (!map)
+ return -ENOMEM;
+
+ of_property_read_u32_array(dev->of_node,
+ "iommu-map", (u32 *)map, size / sizeof(u32));
+
+ nr_map = size / (sizeof(*map));
+
+ crc8_populate_msb(qcom_pcie_crc8_table, QCOM_PCIE_CRC8_POLYNOMIAL);
+
+ /* Registers need to be zero out first */
+ memset_io(bdf_to_sid_base, 0, CRC8_TABLE_SIZE * sizeof(u32));
+
+ /* Look for an available entry to hold the mapping */
+ for (i = 0; i < nr_map; i++) {
+ u16 bdf_be = cpu_to_be16(map[i].bdf);
+ u32 val;
+ u8 hash;
+
+ hash = crc8(qcom_pcie_crc8_table, (u8 *)_be, sizeof(bdf_be),
+ 0);
+
+ val = readl(bdf_to_sid_base + hash * sizeof(u32));
+
+ /* If the register is already populated, look for next
available entry */
+ while (val) {
+ u8 current_hash = hash++;
+ u8 next_mask = 0xff;
+
+ /* If NEXT field is NULL then update it with next hash
*/
+ if (!(val & next_mask)) {
+ val |= (u32)hash;
+ writel(val, bdf_to_sid_base + current_hash *
sizeof(u32));
+ }
+
+ val = readl(bdf_to_sid_base + hash * sizeof(u32));
+ }
+
+ /* BDF [31:16] | SID [15:8] | NEXT [7:0] */
+ val = map[i].bdf << 16 | (map[i].smmu_sid - smmu_sid_base) << 8
| 0;
+ writel(val, bdf_to_sid_base + hash * sizeof(u32));
+ }
+
+ kfree(map);
+
+ return 0;
+}
+
static int
