On Wed, Jan 15, 2025 at 03:06:57PM +0800, Chen Wang wrote:
> From: Chen Wang <unicorn_wang@xxxxxxxxxxx>
>
> Add support for PCIe controller in SG2042 SoC. The controller
> uses the Cadence PCIe core programmed by pcie-cadence*.c. The
> PCIe controller will work in host mode only.
>
Please add more info about the IP. Like IP revision, PCIe Gen, lane count,
etc...
> Signed-off-by: Chen Wang <unicorn_wang@xxxxxxxxxxx>
> ---
> drivers/pci/controller/cadence/Kconfig | 13 +
> drivers/pci/controller/cadence/Makefile | 1 +
> drivers/pci/controller/cadence/pcie-sg2042.c | 528 +++++++++++++++++++
> 3 files changed, 542 insertions(+)
> create mode 100644 drivers/pci/controller/cadence/pcie-sg2042.c
>
> diff --git a/drivers/pci/controller/cadence/Kconfig b/drivers/pci/controller/cadence/Kconfig
> index 8a0044bb3989..292eb2b20e9c 100644
> --- a/drivers/pci/controller/cadence/Kconfig
> +++ b/drivers/pci/controller/cadence/Kconfig
> @@ -42,6 +42,18 @@ config PCIE_CADENCE_PLAT_EP
> endpoint mode. This PCIe controller may be embedded into many
> different vendors SoCs.
>
> +config PCIE_SG2042
> + bool "Sophgo SG2042 PCIe controller (host mode)"
> + depends on ARCH_SOPHGO || COMPILE_TEST
> + depends on OF
> + select IRQ_MSI_LIB
> + select PCI_MSI
> + select PCIE_CADENCE_HOST
> + help
> + Say Y here if you want to support the Sophgo SG2042 PCIe platform
> + controller in host mode. Sophgo SG2042 PCIe controller uses Cadence
> + PCIe core.
> +
> config PCI_J721E
> bool
>
> @@ -67,4 +79,5 @@ config PCI_J721E_EP
> Say Y here if you want to support the TI J721E PCIe platform
> controller in endpoint mode. TI J721E PCIe controller uses Cadence PCIe
> core.
> +
Spurious newline.
> endmenu
> diff --git a/drivers/pci/controller/cadence/Makefile b/drivers/pci/controller/cadence/Makefile
> index 9bac5fb2f13d..4df4456d9539 100644
> --- a/drivers/pci/controller/cadence/Makefile
> +++ b/drivers/pci/controller/cadence/Makefile
> @@ -4,3 +4,4 @@ obj-$(CONFIG_PCIE_CADENCE_HOST) += pcie-cadence-host.o
> obj-$(CONFIG_PCIE_CADENCE_EP) += pcie-cadence-ep.o
> obj-$(CONFIG_PCIE_CADENCE_PLAT) += pcie-cadence-plat.o
> obj-$(CONFIG_PCI_J721E) += pci-j721e.o
> +obj-$(CONFIG_PCIE_SG2042) += pcie-sg2042.o
> diff --git a/drivers/pci/controller/cadence/pcie-sg2042.c b/drivers/pci/controller/cadence/pcie-sg2042.c
> new file mode 100644
> index 000000000000..56797c2af755
> --- /dev/null
> +++ b/drivers/pci/controller/cadence/pcie-sg2042.c
> @@ -0,0 +1,528 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * pcie-sg2042 - PCIe controller driver for Sophgo SG2042 SoC
> + *
> + * Copyright (C) 2024 Sophgo Technology Inc.
> + * Copyright (C) 2024 Chen Wang <unicorn_wang@xxxxxxxxxxx>
> + */
> +
> +#include <linux/bits.h>
> +#include <linux/irq.h>
> +#include <linux/irqchip/chained_irq.h>
> +#include <linux/irqdomain.h>
> +#include <linux/kernel.h>
> +#include <linux/mfd/syscon.h>
> +#include <linux/msi.h>
> +#include <linux/of_address.h>
> +#include <linux/of_irq.h>
> +#include <linux/of_pci.h>
> +#include <linux/platform_device.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/regmap.h>
> +
> +#include "../../../irqchip/irq-msi-lib.h"
> +
> +#include "pcie-cadence.h"
> +
> +/*
> + * SG2042 PCIe controller supports two ways to report MSI:
> + *
> + * - Method A, the PCIe controller implements an MSI interrupt controller
> + * inside, and connect to PLIC upward through one interrupt line.
> + * Provides memory-mapped MSI address, and by programming the upper 32
> + * bits of the address to zero, it can be compatible with old PCIe devices
> + * that only support 32-bit MSI address.
> + *
> + * - Method B, the PCIe controller connects to PLIC upward through an
> + * independent MSI controller "sophgo,sg2042-msi" on the SOC. The MSI
> + * controller provides multiple(up to 32) interrupt sources to PLIC.
> + * Compared with the first method, the advantage is that the interrupt
> + * source is expanded, but because for SG2042, the MSI address provided by
> + * the MSI controller is fixed and only supports 64-bit address(> 2^32),
> + * it is not compatible with old PCIe devices that only support 32-bit MSI
> + * address.
> + *
> + * Method A & B can be configured in DTS, default is Method B.
How to configure them? I can only see "sophgo,sg2042-msi" in the binding.
> + */
> +
> +#define MAX_MSI_IRQS 8
> +#define MAX_MSI_IRQS_PER_CTRL 1
> +#define MAX_MSI_CTRLS (MAX_MSI_IRQS / MAX_MSI_IRQS_PER_CTRL)
> +#define MSI_DEF_NUM_VECTORS MAX_MSI_IRQS
> +#define BYTE_NUM_PER_MSI_VEC 4
> +
> +#define REG_CLEAR 0x0804
> +#define REG_STATUS 0x0810
> +#define REG_LINK0_MSI_ADDR_SIZE 0x085C
> +#define REG_LINK1_MSI_ADDR_SIZE 0x080C
> +#define REG_LINK0_MSI_ADDR_LOW 0x0860
> +#define REG_LINK0_MSI_ADDR_HIGH 0x0864
> +#define REG_LINK1_MSI_ADDR_LOW 0x0868
> +#define REG_LINK1_MSI_ADDR_HIGH 0x086C
> +
> +#define REG_CLEAR_LINK0_BIT 2
> +#define REG_CLEAR_LINK1_BIT 3
> +#define REG_STATUS_LINK0_BIT 2
> +#define REG_STATUS_LINK1_BIT 3
> +
> +#define REG_LINK0_MSI_ADDR_SIZE_MASK GENMASK(15, 0)
> +#define REG_LINK1_MSI_ADDR_SIZE_MASK GENMASK(31, 16)
> +
> +struct sg2042_pcie {
> + struct cdns_pcie *cdns_pcie;
> +
> + struct regmap *syscon;
> +
> + u32 link_id;
> +
> + struct irq_domain *msi_domain;
> +
> + int msi_irq;
> +
> + dma_addr_t msi_phys;
> + void *msi_virt;
> +
> + u32 num_applied_vecs; /* used to speed up ISR */
> +
Get rid of the newline between struct members, please.
> + raw_spinlock_t msi_lock;
> + DECLARE_BITMAP(msi_irq_in_use, MAX_MSI_IRQS);
> +};
> +
[...]
> +static int sg2042_pcie_setup_msi(struct sg2042_pcie *pcie,
> + struct device_node *msi_node)
> +{
> + struct device *dev = pcie->cdns_pcie->dev;
> + struct fwnode_handle *fwnode = of_node_to_fwnode(dev->of_node);
> + struct irq_domain *parent_domain;
> + int ret = 0;
> +
> + if (!of_property_read_bool(msi_node, "msi-controller"))
> + return -ENODEV;
> +
> + ret = of_irq_get_byname(msi_node, "msi");
> + if (ret <= 0) {
> + dev_err(dev, "%pOF: failed to get MSI irq\n", msi_node);
> + return ret;
> + }
> + pcie->msi_irq = ret;
> +
> + irq_set_chained_handler_and_data(pcie->msi_irq,
> + sg2042_pcie_msi_chained_isr, pcie);
> +
> + parent_domain = irq_domain_create_linear(fwnode, MSI_DEF_NUM_VECTORS,
> + &sg2042_pcie_msi_domain_ops, pcie);
> + if (!parent_domain) {
> + dev_err(dev, "%pfw: Failed to create IRQ domain\n", fwnode);
> + return -ENOMEM;
> + }
> + irq_domain_update_bus_token(parent_domain, DOMAIN_BUS_NEXUS);
> +
The MSI controller is wired to PLIC isn't it? If so, why can't you use
hierarchial MSI domain implementation as like other controller drivers?
> + parent_domain->flags |= IRQ_DOMAIN_FLAG_MSI_PARENT;
> + parent_domain->msi_parent_ops = &sg2042_pcie_msi_parent_ops;
> +
> + pcie->msi_domain = parent_domain;
> +
> + ret = sg2042_pcie_init_msi_data(pcie);
> + if (ret) {
> + dev_err(dev, "Failed to initialize MSI data!\n");
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static void sg2042_pcie_free_msi(struct sg2042_pcie *pcie)
> +{
> + struct device *dev = pcie->cdns_pcie->dev;
> +
> + if (pcie->msi_irq)
> + irq_set_chained_handler_and_data(pcie->msi_irq, NULL, NULL);
> +
> + if (pcie->msi_virt)
> + dma_free_coherent(dev, BYTE_NUM_PER_MSI_VEC * MAX_MSI_IRQS,
> + pcie->msi_virt, pcie->msi_phys);
> +}
> +
> +/*
> + * SG2042 only support 4-byte aligned access, so for the rootbus (i.e. to read
> + * the Root Port itself, read32 is required. For non-rootbus (i.e. to read
> + * the PCIe peripheral registers, supports 1/2/4 byte aligned access, so
> + * directly using read should be fine.
> + *
> + * The same is true for write.
> + */
> +static int sg2042_pcie_config_read(struct pci_bus *bus, unsigned int devfn,
> + int where, int size, u32 *value)
> +{
> + if (pci_is_root_bus(bus))
> + return pci_generic_config_read32(bus, devfn, where, size,
> + value);
> +
> + return pci_generic_config_read(bus, devfn, where, size, value);
> +}
> +
> +static int sg2042_pcie_config_write(struct pci_bus *bus, unsigned int devfn,
> + int where, int size, u32 value)
> +{
> + if (pci_is_root_bus(bus))
> + return pci_generic_config_write32(bus, devfn, where, size,
> + value);
> +
> + return pci_generic_config_write(bus, devfn, where, size, value);
> +}
> +
> +static struct pci_ops sg2042_pcie_host_ops = {
> + .map_bus = cdns_pci_map_bus,
> + .read = sg2042_pcie_config_read,
> + .write = sg2042_pcie_config_write,
> +};
> +
> +/* Dummy ops which will be assigned to cdns_pcie.ops, which must be !NULL. */
Because cadence code driver doesn't check for !ops? Please fix it instead. And
the fix is trivial.
> +static const struct cdns_pcie_ops sg2042_cdns_pcie_ops = {};
> +
> +static int sg2042_pcie_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct device_node *np = dev->of_node;
> + struct pci_host_bridge *bridge;
> + struct device_node *np_syscon;
> + struct device_node *msi_node;
> + struct cdns_pcie *cdns_pcie;
> + struct sg2042_pcie *pcie;
> + struct cdns_pcie_rc *rc;
> + struct regmap *syscon;
> + int ret;
> +
> + pcie = devm_kzalloc(dev, sizeof(*pcie), GFP_KERNEL);
> + if (!pcie)
> + return -ENOMEM;
> +
> + bridge = devm_pci_alloc_host_bridge(dev, sizeof(*rc));
> + if (!bridge) {
> + dev_err(dev, "Failed to alloc host bridge!\n");
Use dev_err_probe() throughout the probe function.
> + return -ENOMEM;
> + }
> +
> + bridge->ops = &sg2042_pcie_host_ops;
> +
> + rc = pci_host_bridge_priv(bridge);
> + cdns_pcie = &rc->pcie;
> + cdns_pcie->dev = dev;
> + cdns_pcie->ops = &sg2042_cdns_pcie_ops;
> + pcie->cdns_pcie = cdns_pcie;
> +
> + np_syscon = of_parse_phandle(np, "sophgo,syscon-pcie-ctrl", 0);
> + if (!np_syscon) {
> + dev_err(dev, "Failed to get syscon node\n");
> + return -ENOMEM;
-ENODEV
> + }
> + syscon = syscon_node_to_regmap(np_syscon);
You should drop the np reference count once you are done with it.
> + if (IS_ERR(syscon)) {
> + dev_err(dev, "Failed to get regmap for syscon\n");
> + return -ENOMEM;
PTR_ERR(syscon)
> + }
> + pcie->syscon = syscon;
> +
> + if (of_property_read_u32(np, "sophgo,link-id", &pcie->link_id)) {
> + dev_err(dev, "Unable to parse sophgo,link-id\n");
"Unable to parse \"sophgo,link-id\"\n"
> + return -EINVAL;
> + }
> +
> + platform_set_drvdata(pdev, pcie);
> +
> + pm_runtime_enable(dev);
> +
> + ret = pm_runtime_get_sync(dev);
Use pm_runtime_resume_and_get().
> + if (ret < 0) {
> + dev_err(dev, "pm_runtime_get_sync failed\n");
> + goto err_get_sync;
> + }
> +
> + msi_node = of_parse_phandle(dev->of_node, "msi-parent", 0);
> + if (!msi_node) {
> + dev_err(dev, "Failed to get msi-parent!\n");
> + return -1;
-ENODATA
> + }
> +
> + if (of_device_is_compatible(msi_node, "sophgo,sg2042-pcie-msi")) {
> + ret = sg2042_pcie_setup_msi(pcie, msi_node);
Same as above. np leak here.
- Mani
--
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