diff options
Diffstat (limited to 'arch/s390/pci/pci_irq.c')
| -rw-r--r-- | arch/s390/pci/pci_irq.c | 222 |
1 files changed, 222 insertions, 0 deletions
diff --git a/arch/s390/pci/pci_irq.c b/arch/s390/pci/pci_irq.c new file mode 100644 index 000000000000..3b129cd35b6e --- /dev/null +++ b/arch/s390/pci/pci_irq.c @@ -0,0 +1,222 @@ +// SPDX-License-Identifier: GPL-2.0 +#define KMSG_COMPONENT "zpci" +#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt + +#include <linux/kernel.h> +#include <linux/irq.h> +#include <linux/kernel_stat.h> +#include <linux/pci.h> +#include <linux/msi.h> + +#include <asm/isc.h> +#include <asm/airq.h> + +#define SIC_IRQ_MODE_ALL 0 +#define SIC_IRQ_MODE_SINGLE 1 + +static struct airq_iv *zpci_aisb_iv; +static struct airq_iv *zpci_aibv[ZPCI_NR_DEVICES]; + +/* Modify PCI: Register adapter interruptions */ +static int zpci_set_airq(struct zpci_dev *zdev) +{ + u64 req = ZPCI_CREATE_REQ(zdev->fh, 0, ZPCI_MOD_FC_REG_INT); + struct zpci_fib fib = {0}; + u8 status; + + fib.isc = PCI_ISC; + fib.sum = 1; /* enable summary notifications */ + fib.noi = airq_iv_end(zdev->aibv); + fib.aibv = (unsigned long) zdev->aibv->vector; + fib.aibvo = 0; /* each zdev has its own interrupt vector */ + fib.aisb = (unsigned long) zpci_aisb_iv->vector + (zdev->aisb/64)*8; + fib.aisbo = zdev->aisb & 63; + + return zpci_mod_fc(req, &fib, &status) ? -EIO : 0; +} + +/* Modify PCI: Unregister adapter interruptions */ +static int zpci_clear_airq(struct zpci_dev *zdev) +{ + u64 req = ZPCI_CREATE_REQ(zdev->fh, 0, ZPCI_MOD_FC_DEREG_INT); + struct zpci_fib fib = {0}; + u8 cc, status; + + cc = zpci_mod_fc(req, &fib, &status); + if (cc == 3 || (cc == 1 && status == 24)) + /* Function already gone or IRQs already deregistered. */ + cc = 0; + + return cc ? -EIO : 0; +} + +static struct irq_chip zpci_irq_chip = { + .name = "zPCI", + .irq_unmask = pci_msi_unmask_irq, + .irq_mask = pci_msi_mask_irq, +}; + +static void zpci_irq_handler(struct airq_struct *airq) +{ + unsigned long si, ai; + struct airq_iv *aibv; + int irqs_on = 0; + + inc_irq_stat(IRQIO_PCI); + for (si = 0;;) { + /* Scan adapter summary indicator bit vector */ + si = airq_iv_scan(zpci_aisb_iv, si, airq_iv_end(zpci_aisb_iv)); + if (si == -1UL) { + if (irqs_on++) + /* End of second scan with interrupts on. */ + break; + /* First scan complete, reenable interrupts. */ + if (zpci_set_irq_ctrl(SIC_IRQ_MODE_SINGLE, NULL, PCI_ISC)) + break; + si = 0; + continue; + } + + /* Scan the adapter interrupt vector for this device. */ + aibv = zpci_aibv[si]; + for (ai = 0;;) { + ai = airq_iv_scan(aibv, ai, airq_iv_end(aibv)); + if (ai == -1UL) + break; + inc_irq_stat(IRQIO_MSI); + airq_iv_lock(aibv, ai); + generic_handle_irq(airq_iv_get_data(aibv, ai)); + airq_iv_unlock(aibv, ai); + } + } +} + +int arch_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type) +{ + struct zpci_dev *zdev = to_zpci(pdev); + unsigned int hwirq, msi_vecs; + unsigned long aisb; + struct msi_desc *msi; + struct msi_msg msg; + int rc, irq; + + zdev->aisb = -1UL; + if (type == PCI_CAP_ID_MSI && nvec > 1) + return 1; + msi_vecs = min_t(unsigned int, nvec, zdev->max_msi); + + /* Allocate adapter summary indicator bit */ + aisb = airq_iv_alloc_bit(zpci_aisb_iv); + if (aisb == -1UL) + return -EIO; + zdev->aisb = aisb; + + /* Create adapter interrupt vector */ + zdev->aibv = airq_iv_create(msi_vecs, AIRQ_IV_DATA | AIRQ_IV_BITLOCK); + if (!zdev->aibv) + return -ENOMEM; + + /* Wire up shortcut pointer */ + zpci_aibv[aisb] = zdev->aibv; + + /* Request MSI interrupts */ + hwirq = 0; + for_each_pci_msi_entry(msi, pdev) { + if (hwirq >= msi_vecs) + break; + irq = irq_alloc_desc(0); /* Alloc irq on node 0 */ + if (irq < 0) + return -ENOMEM; + rc = irq_set_msi_desc(irq, msi); + if (rc) + return rc; + irq_set_chip_and_handler(irq, &zpci_irq_chip, + handle_simple_irq); + msg.data = hwirq; + msg.address_lo = zdev->msi_addr & 0xffffffff; + msg.address_hi = zdev->msi_addr >> 32; + pci_write_msi_msg(irq, &msg); + airq_iv_set_data(zdev->aibv, hwirq, irq); + hwirq++; + } + + /* Enable adapter interrupts */ + rc = zpci_set_airq(zdev); + if (rc) + return rc; + + return (msi_vecs == nvec) ? 0 : msi_vecs; +} + +void arch_teardown_msi_irqs(struct pci_dev *pdev) +{ + struct zpci_dev *zdev = to_zpci(pdev); + struct msi_desc *msi; + int rc; + + /* Disable adapter interrupts */ + rc = zpci_clear_airq(zdev); + if (rc) + return; + + /* Release MSI interrupts */ + for_each_pci_msi_entry(msi, pdev) { + if (!msi->irq) + continue; + if (msi->msi_attrib.is_msix) + __pci_msix_desc_mask_irq(msi, 1); + else + __pci_msi_desc_mask_irq(msi, 1, 1); + irq_set_msi_desc(msi->irq, NULL); + irq_free_desc(msi->irq); + msi->msg.address_lo = 0; + msi->msg.address_hi = 0; + msi->msg.data = 0; + msi->irq = 0; + } + + if (zdev->aisb != -1UL) { + zpci_aibv[zdev->aisb] = NULL; + airq_iv_free_bit(zpci_aisb_iv, zdev->aisb); + zdev->aisb = -1UL; + } + if (zdev->aibv) { + airq_iv_release(zdev->aibv); + zdev->aibv = NULL; + } +} + +static struct airq_struct zpci_airq = { + .handler = zpci_irq_handler, + .isc = PCI_ISC, +}; + +int __init zpci_irq_init(void) +{ + int rc; + + rc = register_adapter_interrupt(&zpci_airq); + if (rc) + goto out; + /* Set summary to 1 to be called every time for the ISC. */ + *zpci_airq.lsi_ptr = 1; + + rc = -ENOMEM; + zpci_aisb_iv = airq_iv_create(ZPCI_NR_DEVICES, AIRQ_IV_ALLOC); + if (!zpci_aisb_iv) + goto out_airq; + + zpci_set_irq_ctrl(SIC_IRQ_MODE_SINGLE, NULL, PCI_ISC); + return 0; + +out_airq: + unregister_adapter_interrupt(&zpci_airq); +out: + return rc; +} + +void __init zpci_irq_exit(void) +{ + airq_iv_release(zpci_aisb_iv); + unregister_adapter_interrupt(&zpci_airq); +} |