Hi Jingoo, On Friday 06 September 2013 12:24 PM, Jingoo Han wrote: > This patch adds support for Message Signaled Interrupt in the > Exynos PCIe diver using Synopsys designware PCIe core IP. > > Signed-off-by: Siva Reddy Kallam <siva.kallam@xxxxxxxxxxx> > Signed-off-by: Srikanth T Shivanand <ts.srikanth@xxxxxxxxxxx> > Signed-off-by: Jingoo Han <jg1.han@xxxxxxxxxxx> > Cc: Pratyush Anand <pratyush.anand@xxxxxx> > Cc: Mohit KUMAR <Mohit.KUMAR@xxxxxx> > --- > Changes since v2: > - fixed MAX_MSI_CTRLS because MAX_MSI_IRQS is 32 only > - used __get_free_pages() to allocate msi_data > - used one msi_data and msi_irq_in_use per one RC > - used irq_domain to represent the MSI controller > - removed msi-base irq number from device tree because this is not > a hardware property. > > Changes since v1: > - removed unnecessary exynos_pcie_clear_irq_level() > - updated the bindings documentation > - used new msi_chip infrastructure > - removed ARCH_SUPPORTS_MSI > - replaced #ifdef guards with IS_ENABLED(CONFIG_PCI_MSI) > > drivers/pci/host/pci-exynos.c | 44 +++++++ > drivers/pci/host/pcie-designware.c | 240 ++++++++++++++++++++++++++++++++++++ > drivers/pci/host/pcie-designware.h | 14 +++ > 3 files changed, 298 insertions(+) > > diff --git a/drivers/pci/host/pci-exynos.c b/drivers/pci/host/pci-exynos.c > index 94e096b..f062aca 100644 > --- a/drivers/pci/host/pci-exynos.c > +++ b/drivers/pci/host/pci-exynos.c > @@ -48,6 +48,7 @@ struct exynos_pcie { > #define PCIE_IRQ_SPECIAL 0x008 > #define PCIE_IRQ_EN_PULSE 0x00c > #define PCIE_IRQ_EN_LEVEL 0x010 > +#define IRQ_MSI_ENABLE (0x1 << 2) > #define PCIE_IRQ_EN_SPECIAL 0x014 > #define PCIE_PWR_RESET 0x018 > #define PCIE_CORE_RESET 0x01c > @@ -342,9 +343,36 @@ static irqreturn_t exynos_pcie_irq_handler(int irq, void *arg) > return IRQ_HANDLED; > } > > +static irqreturn_t exynos_pcie_msi_irq_handler(int irq, void *arg) > +{ > + struct pcie_port *pp = arg; > + > + dw_handle_msi_irq(pp); > + > + return IRQ_HANDLED; > +} > + > +static void exynos_pcie_msi_init(struct pcie_port *pp) > +{ > + u32 val; > + struct exynos_pcie *exynos_pcie = to_exynos_pcie(pp); > + > + dw_pcie_msi_init(pp); > + > + /* enable MSI interrupt */ > + val = exynos_elb_readl(exynos_pcie, PCIE_IRQ_EN_LEVEL); > + val |= IRQ_MSI_ENABLE; > + exynos_elb_writel(exynos_pcie, val, PCIE_IRQ_EN_LEVEL); > + return; > +} > + > static void exynos_pcie_enable_interrupts(struct pcie_port *pp) > { > exynos_pcie_enable_irq_pulse(pp); > + > + if (IS_ENABLED(CONFIG_PCI_MSI)) > + exynos_pcie_msi_init(pp); > + > return; > } > > @@ -430,6 +458,22 @@ static int add_pcie_port(struct pcie_port *pp, struct platform_device *pdev) > return ret; > } > > + if (IS_ENABLED(CONFIG_PCI_MSI)) { > + pp->msi_irq = platform_get_irq(pdev, 0); > + if (!pp->msi_irq) { > + dev_err(&pdev->dev, "failed to get msi irq\n"); > + return -ENODEV; > + } > + > + ret = devm_request_irq(&pdev->dev, pp->msi_irq, > + exynos_pcie_msi_irq_handler, > + IRQF_SHARED, "exynos-pcie", pp); > + if (ret) { > + dev_err(&pdev->dev, "failed to request msi irq\n"); > + return ret; > + } > + } > + > pp->root_bus_nr = -1; > pp->ops = &exynos_pcie_host_ops; > > diff --git a/drivers/pci/host/pcie-designware.c b/drivers/pci/host/pcie-designware.c > index c10e9ac..8963017 100644 > --- a/drivers/pci/host/pcie-designware.c > +++ b/drivers/pci/host/pcie-designware.c > @@ -11,8 +11,11 @@ > * published by the Free Software Foundation. > */ > > +#include <linux/irq.h> > +#include <linux/irqdomain.h> > #include <linux/kernel.h> > #include <linux/module.h> > +#include <linux/msi.h> > #include <linux/of_address.h> > #include <linux/pci.h> > #include <linux/pci_regs.h> > @@ -142,6 +145,204 @@ int dw_pcie_wr_own_conf(struct pcie_port *pp, int where, int size, > return ret; > } > > +static struct irq_chip dw_msi_irq_chip = { > + .name = "PCI-MSI", > + .irq_enable = unmask_msi_irq, > + .irq_disable = mask_msi_irq, > + .irq_mask = mask_msi_irq, > + .irq_unmask = unmask_msi_irq, > +}; > + > +/* MSI int handler */ > +void dw_handle_msi_irq(struct pcie_port *pp) > +{ > + unsigned long val; > + int i, pos; > + > + for (i = 0; i < MAX_MSI_CTRLS; i++) { > + dw_pcie_rd_own_conf(pp, PCIE_MSI_INTR0_STATUS + i * 12, 4, > + (u32 *)&val); > + if (val) { > + pos = 0; > + while ((pos = find_next_bit(&val, 32, pos)) != 32) { > + generic_handle_irq(pp->msi_irq_start > + + (i * 32) + pos); > + pos++; > + } > + } > + dw_pcie_wr_own_conf(pp, PCIE_MSI_INTR0_STATUS + i * 12, 4, val); > + } > +} > + > +void dw_pcie_msi_init(struct pcie_port *pp) > +{ > + pp->msi_data = __get_free_pages(GFP_KERNEL, 0); > + > + /* program the msi_data */ > + dw_pcie_wr_own_conf(pp, PCIE_MSI_ADDR_LO, 4, > + virt_to_phys((void *)pp->msi_data)); > + dw_pcie_wr_own_conf(pp, PCIE_MSI_ADDR_HI, 4, 0); > +} > + > +static int find_valid_pos0(struct pcie_port *pp, int msgvec, int pos, int *pos0) > +{ > + int flag = 1; > + > + do { > + pos = find_next_zero_bit(pp->msi_irq_in_use, > + MAX_MSI_IRQS, pos); > + /*if you have reached to the end then get out from here.*/ > + if (pos == MAX_MSI_IRQS) > + return -ENOSPC; > + /* > + * Check if this position is at correct offset.nvec is always a > + * power of two. pos0 must be nvec bit alligned. > + */ > + if (pos % msgvec) > + pos += msgvec - (pos % msgvec); > + else > + flag = 0; > + } while (flag); > + > + *pos0 = pos; > + return 0; > +} > + > +static int assign_irq(int no_irqs, struct msi_desc *desc, int *pos) > +{ > + int res, bit, irq, pos0, pos1, i; > + u32 val; > + struct pcie_port *pp = sys_to_pcie(desc->dev->bus->sysdata); > + > + if (!pp) { > + BUG(); > + return -EINVAL; > + } > + > + pos0 = find_first_zero_bit(pp->msi_irq_in_use, > + MAX_MSI_IRQS); > + if (pos0 % no_irqs) { > + if (find_valid_pos0(pp, no_irqs, pos0, &pos0)) > + goto no_valid_irq; > + } > + if (no_irqs > 1) { > + pos1 = find_next_bit(pp->msi_irq_in_use, > + MAX_MSI_IRQS, pos0); > + /* there must be nvec number of consecutive free bits */ > + while ((pos1 - pos0) < no_irqs) { > + if (find_valid_pos0(pp, no_irqs, pos1, &pos0)) > + goto no_valid_irq; > + pos1 = find_next_bit(pp->msi_irq_in_use, > + MAX_MSI_IRQS, pos0); > + } > + } > + > + irq = (pp->msi_irq_start + pos0); > + > + if ((irq + no_irqs) > (pp->msi_irq_start + MAX_MSI_IRQS-1)) > + goto no_valid_irq; > + > + i = 0; > + while (i < no_irqs) { > + set_bit(pos0 + i, pp->msi_irq_in_use); > + irq_alloc_descs((irq + i), (irq + i), 1, 0); > + irq_set_msi_desc(irq + i, desc); > + /*Enable corresponding interrupt in MSI interrupt controller */ > + res = ((pos0 + i) / 32) * 12; > + bit = (pos0 + i) % 32; > + dw_pcie_rd_own_conf(pp, PCIE_MSI_INTR0_ENABLE + res, 4, &val); > + val |= 1 << bit; > + dw_pcie_wr_own_conf(pp, PCIE_MSI_INTR0_ENABLE + res, 4, val); > + i++; > + } > + > + *pos = pos0; > + return irq; > + > +no_valid_irq: > + *pos = pos0; > + return -ENOSPC; > +} > + > +static void clear_irq(unsigned int irq) > +{ > + int res, bit, val, pos; > + struct irq_desc *desc; > + struct msi_desc *msi; > + struct pcie_port *pp; > + > + /* get the port structure */ > + desc = irq_to_desc(irq); > + msi = irq_desc_get_msi_desc(desc); > + pp = sys_to_pcie(msi->dev->bus->sysdata); > + if (!pp) { > + BUG(); > + return; > + } > + > + pos = irq - pp->msi_irq_start; > + > + irq_free_desc(irq); > + > + clear_bit(pos, pp->msi_irq_in_use); > + > + /* Disable corresponding interrupt on MSI interrupt controller */ > + res = (pos / 32) * 12; > + bit = pos % 32; > + dw_pcie_rd_own_conf(pp, PCIE_MSI_INTR0_ENABLE + res, 4, &val); > + val &= ~(1 << bit); > + dw_pcie_wr_own_conf(pp, PCIE_MSI_INTR0_ENABLE + res, 4, val); > +} > + > +static int dw_msi_setup_irq(struct msi_chip *chip, struct pci_dev *pdev, > + struct msi_desc *desc) > +{ > + int irq, pos, msgvec; > + u16 msg_ctr; > + struct msi_msg msg; > + struct pcie_port *pp = sys_to_pcie(pdev->bus->sysdata); > + > + if (!pp) { > + BUG(); > + return -EINVAL; > + } > + > + pci_read_config_word(pdev, desc->msi_attrib.pos+PCI_MSI_FLAGS, > + &msg_ctr); > + msgvec = (msg_ctr&PCI_MSI_FLAGS_QSIZE) >> 4; > + if (msgvec == 0) > + msgvec = (msg_ctr & PCI_MSI_FLAGS_QMASK) >> 1; > + if (msgvec > 5) > + msgvec = 0; > + > + irq = assign_irq((1 << msgvec), desc, &pos); > + if (irq < 0) > + return irq; > + > + msg_ctr &= ~PCI_MSI_FLAGS_QSIZE; > + msg_ctr |= msgvec << 4; > + pci_write_config_word(pdev, desc->msi_attrib.pos + PCI_MSI_FLAGS, > + msg_ctr); > + desc->msi_attrib.multiple = msgvec; > + > + msg.address_lo = virt_to_phys((void *)pp->msi_data); > + msg.address_hi = 0x0; > + msg.data = pos; > + write_msi_msg(irq, &msg); > + > + return 0; > +} > + > +static void dw_msi_teardown_irq(struct msi_chip *chip, unsigned int irq) > +{ > + clear_irq(irq); > +} > + > +static struct msi_chip dw_pcie_msi_chip = { > + .setup_irq = dw_msi_setup_irq, > + .teardown_irq = dw_msi_teardown_irq, > +}; > + > int dw_pcie_link_up(struct pcie_port *pp) > { > if (pp->ops->link_up) > @@ -150,6 +351,20 @@ int dw_pcie_link_up(struct pcie_port *pp) > return 0; > } > > +static int dw_pcie_msi_map(struct irq_domain *domain, unsigned int irq, > + irq_hw_number_t hwirq) > +{ > + irq_set_chip_and_handler(irq, &dw_msi_irq_chip, handle_simple_irq); > + irq_set_chip_data(irq, domain->host_data); > + set_irq_flags(irq, IRQF_VALID); > + > + return 0; > +} > + > +static const struct irq_domain_ops msi_domain_ops = { > + .map = dw_pcie_msi_map, > +}; > + > int __init dw_pcie_host_init(struct pcie_port *pp) > { > struct device_node *np = pp->dev->of_node; > @@ -157,6 +372,8 @@ int __init dw_pcie_host_init(struct pcie_port *pp) > struct of_pci_range_parser parser; > u32 val; > > + struct irq_domain *irq_domain; > + > if (of_pci_range_parser_init(&parser, np)) { > dev_err(pp->dev, "missing ranges property\n"); > return -EINVAL; > @@ -223,6 +440,18 @@ int __init dw_pcie_host_init(struct pcie_port *pp) > return -EINVAL; > } > > + if (IS_ENABLED(CONFIG_PCI_MSI)) { > + irq_domain = irq_domain_add_linear(pp->dev->of_node, > + MAX_MSI_IRQS, &msi_domain_ops, > + &dw_pcie_msi_chip); > + if (!irq_domain) { > + dev_err(pp->dev, "irq domain init failed\n"); > + return -ENXIO; > + } > + > + pp->msi_irq_start = irq_find_mapping(irq_domain, 0); Where is the irq_create_mapping done for this irq domain? Is that not needed? Without that I'm not getting the correct irq number. Thanks Kishon -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html