Hi Zhang,
On 20/04/18 06:25, honghui.zhang@xxxxxxxxxxxx wrote:
> From: Honghui Zhang <honghui.zhang@xxxxxxxxxxxx>
>
> Using irq_chip solution to setup IRQs for the consistent with IRQ framework.
>
> Signed-off-by: Honghui Zhang <honghui.zhang@xxxxxxxxxxxx>
> ---
> drivers/pci/host/pcie-mediatek.c | 192 +++++++++++++++++++++------------------
> 1 file changed, 105 insertions(+), 87 deletions(-)
>
> diff --git a/drivers/pci/host/pcie-mediatek.c b/drivers/pci/host/pcie-mediatek.c
> index c3dc549..1d9c6f1 100644
> --- a/drivers/pci/host/pcie-mediatek.c
> +++ b/drivers/pci/host/pcie-mediatek.c
> @@ -11,8 +11,10 @@
> #include <linux/delay.h>
> #include <linux/iopoll.h>
> #include <linux/irq.h>
> +#include <linux/irqchip/chained_irq.h>
> #include <linux/irqdomain.h>
> #include <linux/kernel.h>
> +#include <linux/msi.h>
> #include <linux/of_address.h>
> #include <linux/of_pci.h>
> #include <linux/of_platform.h>
> @@ -130,14 +132,12 @@ struct mtk_pcie_port;
> /**
> * struct mtk_pcie_soc - differentiate between host generations
> * @need_fix_class_id: whether this host's class ID needed to be fixed or not
> - * @has_msi: whether this host supports MSI interrupts or not
> * @ops: pointer to configuration access functions
> * @startup: pointer to controller setting functions
> * @setup_irq: pointer to initialize IRQ functions
> */
> struct mtk_pcie_soc {
> bool need_fix_class_id;
> - bool has_msi;
> struct pci_ops *ops;
> int (*startup)(struct mtk_pcie_port *port);
> int (*setup_irq)(struct mtk_pcie_port *port, struct device_node *node);
> @@ -161,7 +161,9 @@ struct mtk_pcie_soc {
> * @lane: lane count
> * @slot: port slot
> * @irq_domain: legacy INTx IRQ domain
> + * @inner_domain: inner IRQ domain
> * @msi_domain: MSI IRQ domain
> + * @lock: protect the msi_irq_in_use bitmap
> * @msi_irq_in_use: bit map for assigned MSI IRQ
> */
> struct mtk_pcie_port {
> @@ -179,7 +181,9 @@ struct mtk_pcie_port {
> u32 lane;
> u32 slot;
> struct irq_domain *irq_domain;
> + struct irq_domain *inner_domain;
> struct irq_domain *msi_domain;
> + struct mutex lock;
> DECLARE_BITMAP(msi_irq_in_use, MTK_MSI_IRQS_NUM);
> };
>
> @@ -446,103 +450,122 @@ static int mtk_pcie_startup_port_v2(struct mtk_pcie_port *port)
> return 0;
> }
>
> -static int mtk_pcie_msi_alloc(struct mtk_pcie_port *port)
> +static void mtk_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
> {
> - int msi;
> + struct mtk_pcie_port *port = irq_data_get_irq_chip_data(data);
> + phys_addr_t addr;
>
> - msi = find_first_zero_bit(port->msi_irq_in_use, MTK_MSI_IRQS_NUM);
> - if (msi < MTK_MSI_IRQS_NUM)
> - set_bit(msi, port->msi_irq_in_use);
> - else
> - return -ENOSPC;
> + /* MT2712/MT7622 only support 32-bit MSI addresses */
> + addr = virt_to_phys(port->base + PCIE_MSI_VECTOR);
> + msg->address_hi = 0;
> + msg->address_lo = lower_32_bits(addr);
>
> - return msi;
> + msg->data = data->hwirq;
> +
> + dev_dbg(port->pcie->dev, "msi#%d address_hi %#x address_lo %#x\n",
> + (int)data->hwirq, msg->address_hi, msg->address_lo);
> }
>
> -static void mtk_pcie_msi_free(struct mtk_pcie_port *port, unsigned long hwirq)
> +static int mtk_msi_set_affinity(struct irq_data *irq_data,
> + const struct cpumask *mask, bool force)
> {
> - clear_bit(hwirq, port->msi_irq_in_use);
> + return -EINVAL;
> }
>
> -static int mtk_pcie_msi_setup_irq(struct msi_controller *chip,
> - struct pci_dev *pdev, struct msi_desc *desc)
> -{
> - struct mtk_pcie_port *port;
> - struct msi_msg msg;
> - unsigned int irq;
> - int hwirq;
> - phys_addr_t msg_addr;
> +static struct irq_chip mtk_msi_bottom_irq_chip = {
> + .name = "MTK MSI",
> + .irq_compose_msi_msg = mtk_compose_msi_msg,
> + .irq_set_affinity = mtk_msi_set_affinity,
> + .irq_mask = pci_msi_mask_irq,
> + .irq_unmask = pci_msi_unmask_irq,
> +};
>
> - port = mtk_pcie_find_port(pdev->bus, pdev->devfn);
> - if (!port)
> - return -EINVAL;
> +static int mtk_pcie_irq_domain_alloc(struct irq_domain *domain, unsigned int virq,
> + unsigned int nr_irqs, void *args)
> +{
> + struct mtk_pcie_port *port = domain->host_data;
> + unsigned long bit;
>
> - hwirq = mtk_pcie_msi_alloc(port);
> - if (hwirq < 0)
> - return hwirq;
> + WARN_ON(nr_irqs != 1);
> + mutex_lock(&port->lock);
>
> - irq = irq_create_mapping(port->msi_domain, hwirq);
> - if (!irq) {
> - mtk_pcie_msi_free(port, hwirq);
> - return -EINVAL;
> + bit = find_first_zero_bit(port->msi_irq_in_use, MTK_MSI_IRQS_NUM);
> + if (bit >= MTK_MSI_IRQS_NUM) {
> + mutex_unlock(&port->lock);
> + return -ENOSPC;
> }
>
> - chip->dev = &pdev->dev;
> -
> - irq_set_msi_desc(irq, desc);
> + __set_bit(bit, port->msi_irq_in_use);
>
> - /* MT2712/MT7622 only support 32-bit MSI addresses */
> - msg_addr = virt_to_phys(port->base + PCIE_MSI_VECTOR);
> - msg.address_hi = 0;
> - msg.address_lo = lower_32_bits(msg_addr);
> - msg.data = hwirq;
> + mutex_unlock(&port->lock);
>
> - pci_write_msi_msg(irq, &msg);
> + irq_domain_set_info(domain, virq, bit, &mtk_msi_bottom_irq_chip,
> + domain->host_data, handle_simple_irq,
Why don't you handle the interrupt as an edge interrupt
(handle_edge_irq)? That's what it really is, and the fact that you use
"handle_simple_irq" makes me think that wou're papering over some other
issue (see below).
> + NULL, NULL);
>
> return 0;
> }
>
> -static void mtk_msi_teardown_irq(struct msi_controller *chip, unsigned int irq)
> +static void mtk_pcie_irq_domain_free(struct irq_domain *domain,
> + unsigned int virq, unsigned int nr_irqs)
> {
> - struct pci_dev *pdev = to_pci_dev(chip->dev);
> - struct irq_data *d = irq_get_irq_data(irq);
> - irq_hw_number_t hwirq = irqd_to_hwirq(d);
> - struct mtk_pcie_port *port;
> + struct irq_data *d = irq_domain_get_irq_data(domain, virq);
> + struct mtk_pcie_port *port = irq_data_get_irq_chip_data(d);
>
> - port = mtk_pcie_find_port(pdev->bus, pdev->devfn);
> - if (!port)
> - return;
> + mutex_lock(&port->lock);
> +
> + if (!test_bit(d->hwirq, port->msi_irq_in_use))
> + dev_err(port->pcie->dev, "trying to free unused MSI#%lu\n",
> + d->hwirq);
> + else
> + __clear_bit(d->hwirq, port->msi_irq_in_use);
>
> - irq_dispose_mapping(irq);
> - mtk_pcie_msi_free(port, hwirq);
> + mutex_unlock(&port->lock);
> +
> + irq_domain_free_irqs_parent(domain, virq, nr_irqs);
> }
>
> -static struct msi_controller mtk_pcie_msi_chip = {
> - .setup_irq = mtk_pcie_msi_setup_irq,
> - .teardown_irq = mtk_msi_teardown_irq,
> +static const struct irq_domain_ops msi_domain_ops = {
> + .alloc = mtk_pcie_irq_domain_alloc,
> + .free = mtk_pcie_irq_domain_free,
> };
>
> static struct irq_chip mtk_msi_irq_chip = {
> .name = "MTK PCIe MSI",
> - .irq_enable = pci_msi_unmask_irq,
> - .irq_disable = pci_msi_mask_irq,
> .irq_mask = pci_msi_mask_irq,
> .irq_unmask = pci_msi_unmask_irq,
> };
>
> -static int mtk_pcie_msi_map(struct irq_domain *domain, unsigned int irq,
> - irq_hw_number_t hwirq)
> +static struct msi_domain_info mtk_msi_domain_info = {
> + .flags = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
> + MSI_FLAG_PCI_MSIX),
> + .chip = &mtk_msi_irq_chip,
> +};
> +
> +static int mtk_pcie_allocate_msi_domains(struct mtk_pcie_port *port)
> {
> - irq_set_chip_and_handler(irq, &mtk_msi_irq_chip, handle_simple_irq);
> - irq_set_chip_data(irq, domain->host_data);
> + struct fwnode_handle *fwnode = of_node_to_fwnode(port->pcie->dev->of_node);
> +
> + mutex_init(&port->lock);
> +
> + port->inner_domain = irq_domain_create_linear(fwnode, MTK_MSI_IRQS_NUM,
> + &msi_domain_ops, port);
> + if (!port->inner_domain) {
> + dev_err(port->pcie->dev, "failed to create IRQ domain\n");
> + return -ENOMEM;
> + }
> +
> + port->msi_domain = pci_msi_create_irq_domain(fwnode, &mtk_msi_domain_info,
> + port->inner_domain);
> + if (!port->msi_domain) {
> + dev_err(port->pcie->dev, "failed to create MSI domain\n");
> + irq_domain_remove(port->inner_domain);
> + return -ENOMEM;
> + }
>
> return 0;
> }
>
> -static const struct irq_domain_ops msi_domain_ops = {
> - .map = mtk_pcie_msi_map,
> -};
> -
> static void mtk_pcie_enable_msi(struct mtk_pcie_port *port)
> {
> u32 val;
> @@ -575,6 +598,7 @@ static int mtk_pcie_init_irq_domain(struct mtk_pcie_port *port,
> {
> struct device *dev = port->pcie->dev;
> struct device_node *pcie_intc_node;
> + int ret;
>
> /* Setup INTx */
> pcie_intc_node = of_get_next_child(node, NULL);
> @@ -591,27 +615,28 @@ static int mtk_pcie_init_irq_domain(struct mtk_pcie_port *port,
> }
>
> if (IS_ENABLED(CONFIG_PCI_MSI)) {
> - port->msi_domain = irq_domain_add_linear(node, MTK_MSI_IRQS_NUM,
> - &msi_domain_ops,
> - &mtk_pcie_msi_chip);
> - if (!port->msi_domain) {
> - dev_err(dev, "failed to create MSI IRQ domain\n");
> - return -ENODEV;
> - }
> + ret = mtk_pcie_allocate_msi_domains(port);
> + if (ret)
> + return ret;
> +
> mtk_pcie_enable_msi(port);
> }
>
> return 0;
> }
>
> -static irqreturn_t mtk_pcie_intr_handler(int irq, void *data)
> +static void mtk_pcie_intr_handler(struct irq_desc *desc)
> {
> - struct mtk_pcie_port *port = (struct mtk_pcie_port *)data;
> + struct mtk_pcie_port *port = irq_desc_get_handler_data(desc);
> + struct irq_chip *irqchip = irq_desc_get_chip(desc);
> unsigned long status;
> u32 virq;
> u32 bit = INTX_SHIFT;
>
> - while ((status = readl(port->base + PCIE_INT_STATUS)) & INTX_MASK) {
> + chained_irq_enter(irqchip, desc);
> +
> + status = readl(port->base + PCIE_INT_STATUS);
> + if (status & INTX_MASK) {
> for_each_set_bit_from(bit, &status, PCI_NUM_INTX + INTX_SHIFT) {
> /* Clear the INTx */
> writel(1 << bit, port->base + PCIE_INT_STATUS);
> @@ -622,14 +647,14 @@ static irqreturn_t mtk_pcie_intr_handler(int irq, void *data)
> }
>
> if (IS_ENABLED(CONFIG_PCI_MSI)) {
> - while ((status = readl(port->base + PCIE_INT_STATUS)) & MSI_STATUS) {
> + if (status & MSI_STATUS) {
> unsigned long imsi_status;
>
> while ((imsi_status = readl(port->base + PCIE_IMSI_STATUS))) {
> for_each_set_bit(bit, &imsi_status, MTK_MSI_IRQS_NUM) {
> /* Clear the MSI */
> writel(1 << bit, port->base + PCIE_IMSI_STATUS);
This write suspiciously looks like an "ack" operation on the controller.
Why isn't it part of the irqchip as a first class method?
> - virq = irq_find_mapping(port->msi_domain, bit);
> + virq = irq_find_mapping(port->inner_domain, bit);
> generic_handle_irq(virq);
> }
> }
> @@ -638,7 +663,9 @@ static irqreturn_t mtk_pcie_intr_handler(int irq, void *data)
> }
> }
>
> - return IRQ_HANDLED;
> + chained_irq_exit(irqchip, desc);
> +
> + return;
> }
>
> static int mtk_pcie_setup_irq(struct mtk_pcie_port *port,
> @@ -649,20 +676,15 @@ static int mtk_pcie_setup_irq(struct mtk_pcie_port *port,
> struct platform_device *pdev = to_platform_device(dev);
> int err, irq;
>
> - irq = platform_get_irq(pdev, port->slot);
> - err = devm_request_irq(dev, irq, mtk_pcie_intr_handler,
> - IRQF_SHARED, "mtk-pcie", port);
> - if (err) {
> - dev_err(dev, "unable to request IRQ %d\n", irq);
> - return err;
> - }
> -
> err = mtk_pcie_init_irq_domain(port, node);
> if (err) {
> dev_err(dev, "failed to init PCIe IRQ domain\n");
> return err;
> }
>
> + irq = platform_get_irq(pdev, port->slot);
> + irq_set_chained_handler_and_data(irq, mtk_pcie_intr_handler, port);
> +
> return 0;
> }
>
> @@ -1096,8 +1118,6 @@ static int mtk_pcie_register_host(struct pci_host_bridge *host)
> host->map_irq = of_irq_parse_and_map_pci;
> host->swizzle_irq = pci_common_swizzle;
> host->sysdata = pcie;
> - if (IS_ENABLED(CONFIG_PCI_MSI) && pcie->soc->has_msi)
> - host->msi = &mtk_pcie_msi_chip;
>
> err = pci_scan_root_bus_bridge(host);
> if (err < 0)
> @@ -1159,7 +1179,6 @@ static const struct mtk_pcie_soc mtk_pcie_soc_v1 = {
> };
>
> static const struct mtk_pcie_soc mtk_pcie_soc_mt2712 = {
> - .has_msi = true,
> .ops = &mtk_pcie_ops_v2,
> .startup = mtk_pcie_startup_port_v2,
> .setup_irq = mtk_pcie_setup_irq,
> @@ -1167,7 +1186,6 @@ static const struct mtk_pcie_soc mtk_pcie_soc_mt2712 = {
>
> static const struct mtk_pcie_soc mtk_pcie_soc_mt7622 = {
> .need_fix_class_id = true,
> - .has_msi = true,
> .ops = &mtk_pcie_ops_v2,
> .startup = mtk_pcie_startup_port_v2,
> .setup_irq = mtk_pcie_setup_irq,
>
Thanks,
M.
--
Jazz is not dead. It just smells funny...
