Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/s390/pci/pci_irq.c b/arch/s390/pci/pci_irq.c
new file mode 100644
index 0000000..fbe97ab
--- /dev/null
+++ b/arch/s390/pci/pci_irq.c
@@ -0,0 +1,486 @@
+// 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 <linux/smp.h>
+
+#include <asm/isc.h>
+#include <asm/airq.h>
+
+static enum {FLOATING, DIRECTED} irq_delivery;
+
+#define SIC_IRQ_MODE_ALL 0
+#define SIC_IRQ_MODE_SINGLE 1
+#define SIC_IRQ_MODE_DIRECT 4
+#define SIC_IRQ_MODE_D_ALL 16
+#define SIC_IRQ_MODE_D_SINGLE 17
+#define SIC_IRQ_MODE_SET_CPU 18
+
+/*
+ * summary bit vector
+ * FLOATING - summary bit per function
+ * DIRECTED - summary bit per cpu (only used in fallback path)
+ */
+static struct airq_iv *zpci_sbv;
+
+/*
+ * interrupt bit vectors
+ * FLOATING - interrupt bit vector per function
+ * DIRECTED - interrupt bit vector per cpu
+ */
+static struct airq_iv **zpci_ibv;
+
+/* 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.fmt0.isc = PCI_ISC;
+ fib.fmt0.sum = 1; /* enable summary notifications */
+ fib.fmt0.noi = airq_iv_end(zdev->aibv);
+ fib.fmt0.aibv = (unsigned long) zdev->aibv->vector;
+ fib.fmt0.aibvo = 0; /* each zdev has its own interrupt vector */
+ fib.fmt0.aisb = (unsigned long) zpci_sbv->vector + (zdev->aisb/64)*8;
+ fib.fmt0.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;
+}
+
+/* Modify PCI: Register CPU directed interruptions */
+static int zpci_set_directed_irq(struct zpci_dev *zdev)
+{
+ u64 req = ZPCI_CREATE_REQ(zdev->fh, 0, ZPCI_MOD_FC_REG_INT_D);
+ struct zpci_fib fib = {0};
+ u8 status;
+
+ fib.fmt = 1;
+ fib.fmt1.noi = zdev->msi_nr_irqs;
+ fib.fmt1.dibvo = zdev->msi_first_bit;
+
+ return zpci_mod_fc(req, &fib, &status) ? -EIO : 0;
+}
+
+/* Modify PCI: Unregister CPU directed interruptions */
+static int zpci_clear_directed_irq(struct zpci_dev *zdev)
+{
+ u64 req = ZPCI_CREATE_REQ(zdev->fh, 0, ZPCI_MOD_FC_DEREG_INT_D);
+ struct zpci_fib fib = {0};
+ u8 cc, status;
+
+ fib.fmt = 1;
+ 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 int zpci_set_irq_affinity(struct irq_data *data, const struct cpumask *dest,
+ bool force)
+{
+ struct msi_desc *entry = irq_get_msi_desc(data->irq);
+ struct msi_msg msg = entry->msg;
+
+ msg.address_lo &= 0xff0000ff;
+ msg.address_lo |= (cpumask_first(dest) << 8);
+ pci_write_msi_msg(data->irq, &msg);
+
+ return IRQ_SET_MASK_OK;
+}
+
+static struct irq_chip zpci_irq_chip = {
+ .name = "PCI-MSI",
+ .irq_unmask = pci_msi_unmask_irq,
+ .irq_mask = pci_msi_mask_irq,
+ .irq_set_affinity = zpci_set_irq_affinity,
+};
+
+static void zpci_handle_cpu_local_irq(bool rescan)
+{
+ struct airq_iv *dibv = zpci_ibv[smp_processor_id()];
+ unsigned long bit;
+ int irqs_on = 0;
+
+ for (bit = 0;;) {
+ /* Scan the directed IRQ bit vector */
+ bit = airq_iv_scan(dibv, bit, airq_iv_end(dibv));
+ if (bit == -1UL) {
+ if (!rescan || irqs_on++)
+ /* End of second scan with interrupts on. */
+ break;
+ /* First scan complete, reenable interrupts. */
+ if (zpci_set_irq_ctrl(SIC_IRQ_MODE_D_SINGLE, PCI_ISC))
+ break;
+ bit = 0;
+ continue;
+ }
+ inc_irq_stat(IRQIO_MSI);
+ generic_handle_irq(airq_iv_get_data(dibv, bit));
+ }
+}
+
+struct cpu_irq_data {
+ call_single_data_t csd;
+ atomic_t scheduled;
+};
+static DEFINE_PER_CPU_SHARED_ALIGNED(struct cpu_irq_data, irq_data);
+
+static void zpci_handle_remote_irq(void *data)
+{
+ atomic_t *scheduled = data;
+
+ do {
+ zpci_handle_cpu_local_irq(false);
+ } while (atomic_dec_return(scheduled));
+}
+
+static void zpci_handle_fallback_irq(void)
+{
+ struct cpu_irq_data *cpu_data;
+ unsigned long cpu;
+ int irqs_on = 0;
+
+ for (cpu = 0;;) {
+ cpu = airq_iv_scan(zpci_sbv, cpu, airq_iv_end(zpci_sbv));
+ if (cpu == -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, PCI_ISC))
+ break;
+ cpu = 0;
+ continue;
+ }
+ cpu_data = &per_cpu(irq_data, cpu);
+ if (atomic_inc_return(&cpu_data->scheduled) > 1)
+ continue;
+
+ cpu_data->csd.func = zpci_handle_remote_irq;
+ cpu_data->csd.info = &cpu_data->scheduled;
+ cpu_data->csd.flags = 0;
+ smp_call_function_single_async(cpu, &cpu_data->csd);
+ }
+}
+
+static void zpci_directed_irq_handler(struct airq_struct *airq, bool floating)
+{
+ if (floating) {
+ inc_irq_stat(IRQIO_PCF);
+ zpci_handle_fallback_irq();
+ } else {
+ inc_irq_stat(IRQIO_PCD);
+ zpci_handle_cpu_local_irq(true);
+ }
+}
+
+static void zpci_floating_irq_handler(struct airq_struct *airq, bool floating)
+{
+ unsigned long si, ai;
+ struct airq_iv *aibv;
+ int irqs_on = 0;
+
+ inc_irq_stat(IRQIO_PCF);
+ for (si = 0;;) {
+ /* Scan adapter summary indicator bit vector */
+ si = airq_iv_scan(zpci_sbv, si, airq_iv_end(zpci_sbv));
+ 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, PCI_ISC))
+ break;
+ si = 0;
+ continue;
+ }
+
+ /* Scan the adapter interrupt vector for this device. */
+ aibv = zpci_ibv[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, cpu;
+ unsigned long bit;
+ struct msi_desc *msi;
+ struct msi_msg msg;
+ int rc, irq;
+
+ zdev->aisb = -1UL;
+ zdev->msi_first_bit = -1U;
+ if (type == PCI_CAP_ID_MSI && nvec > 1)
+ return 1;
+ msi_vecs = min_t(unsigned int, nvec, zdev->max_msi);
+
+ if (irq_delivery == DIRECTED) {
+ /* Allocate cpu vector bits */
+ bit = airq_iv_alloc(zpci_ibv[0], msi_vecs);
+ if (bit == -1UL)
+ return -EIO;
+ } else {
+ /* Allocate adapter summary indicator bit */
+ bit = airq_iv_alloc_bit(zpci_sbv);
+ if (bit == -1UL)
+ return -EIO;
+ zdev->aisb = bit;
+
+ /* 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_ibv[bit] = zdev->aibv;
+ /* Each function has its own interrupt vector */
+ bit = 0;
+ }
+
+ /* Request MSI interrupts */
+ hwirq = bit;
+ for_each_pci_msi_entry(msi, pdev) {
+ rc = -EIO;
+ if (hwirq - bit >= msi_vecs)
+ break;
+ irq = __irq_alloc_descs(-1, 0, 1, 0, THIS_MODULE, msi->affinity);
+ 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_percpu_irq);
+ msg.data = hwirq - bit;
+ if (irq_delivery == DIRECTED) {
+ msg.address_lo = zdev->msi_addr & 0xff0000ff;
+ msg.address_lo |= msi->affinity ?
+ (cpumask_first(&msi->affinity->mask) << 8) : 0;
+ for_each_possible_cpu(cpu) {
+ airq_iv_set_data(zpci_ibv[cpu], hwirq, irq);
+ }
+ } else {
+ msg.address_lo = zdev->msi_addr & 0xffffffff;
+ airq_iv_set_data(zdev->aibv, hwirq, irq);
+ }
+ msg.address_hi = zdev->msi_addr >> 32;
+ pci_write_msi_msg(irq, &msg);
+ hwirq++;
+ }
+
+ zdev->msi_first_bit = bit;
+ zdev->msi_nr_irqs = msi_vecs;
+
+ if (irq_delivery == DIRECTED)
+ rc = zpci_set_directed_irq(zdev);
+ else
+ 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 interrupts */
+ if (irq_delivery == DIRECTED)
+ rc = zpci_clear_directed_irq(zdev);
+ else
+ 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_ibv[zdev->aisb] = NULL;
+ airq_iv_free_bit(zpci_sbv, zdev->aisb);
+ zdev->aisb = -1UL;
+ }
+ if (zdev->aibv) {
+ airq_iv_release(zdev->aibv);
+ zdev->aibv = NULL;
+ }
+
+ if ((irq_delivery == DIRECTED) && zdev->msi_first_bit != -1U)
+ airq_iv_free(zpci_ibv[0], zdev->msi_first_bit, zdev->msi_nr_irqs);
+}
+
+static struct airq_struct zpci_airq = {
+ .handler = zpci_floating_irq_handler,
+ .isc = PCI_ISC,
+};
+
+static void __init cpu_enable_directed_irq(void *unused)
+{
+ union zpci_sic_iib iib = {{0}};
+
+ iib.cdiib.dibv_addr = (u64) zpci_ibv[smp_processor_id()]->vector;
+
+ __zpci_set_irq_ctrl(SIC_IRQ_MODE_SET_CPU, 0, &iib);
+ zpci_set_irq_ctrl(SIC_IRQ_MODE_D_SINGLE, PCI_ISC);
+}
+
+static int __init zpci_directed_irq_init(void)
+{
+ union zpci_sic_iib iib = {{0}};
+ unsigned int cpu;
+
+ zpci_sbv = airq_iv_create(num_possible_cpus(), 0);
+ if (!zpci_sbv)
+ return -ENOMEM;
+
+ iib.diib.isc = PCI_ISC;
+ iib.diib.nr_cpus = num_possible_cpus();
+ iib.diib.disb_addr = (u64) zpci_sbv->vector;
+ __zpci_set_irq_ctrl(SIC_IRQ_MODE_DIRECT, 0, &iib);
+
+ zpci_ibv = kcalloc(num_possible_cpus(), sizeof(*zpci_ibv),
+ GFP_KERNEL);
+ if (!zpci_ibv)
+ return -ENOMEM;
+
+ for_each_possible_cpu(cpu) {
+ /*
+ * Per CPU IRQ vectors look the same but bit-allocation
+ * is only done on the first vector.
+ */
+ zpci_ibv[cpu] = airq_iv_create(cache_line_size() * BITS_PER_BYTE,
+ AIRQ_IV_DATA |
+ AIRQ_IV_CACHELINE |
+ (!cpu ? AIRQ_IV_ALLOC : 0));
+ if (!zpci_ibv[cpu])
+ return -ENOMEM;
+ }
+ on_each_cpu(cpu_enable_directed_irq, NULL, 1);
+
+ zpci_irq_chip.irq_set_affinity = zpci_set_irq_affinity;
+
+ return 0;
+}
+
+static int __init zpci_floating_irq_init(void)
+{
+ zpci_ibv = kcalloc(ZPCI_NR_DEVICES, sizeof(*zpci_ibv), GFP_KERNEL);
+ if (!zpci_ibv)
+ return -ENOMEM;
+
+ zpci_sbv = airq_iv_create(ZPCI_NR_DEVICES, AIRQ_IV_ALLOC);
+ if (!zpci_sbv)
+ goto out_free;
+
+ return 0;
+
+out_free:
+ kfree(zpci_ibv);
+ return -ENOMEM;
+}
+
+int __init zpci_irq_init(void)
+{
+ int rc;
+
+ irq_delivery = sclp.has_dirq ? DIRECTED : FLOATING;
+ if (s390_pci_force_floating)
+ irq_delivery = FLOATING;
+
+ if (irq_delivery == DIRECTED)
+ zpci_airq.handler = zpci_directed_irq_handler;
+
+ 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;
+
+ switch (irq_delivery) {
+ case FLOATING:
+ rc = zpci_floating_irq_init();
+ break;
+ case DIRECTED:
+ rc = zpci_directed_irq_init();
+ break;
+ }
+
+ if (rc)
+ goto out_airq;
+
+ /*
+ * Enable floating IRQs (with suppression after one IRQ). When using
+ * directed IRQs this enables the fallback path.
+ */
+ zpci_set_irq_ctrl(SIC_IRQ_MODE_SINGLE, PCI_ISC);
+
+ return 0;
+out_airq:
+ unregister_adapter_interrupt(&zpci_airq);
+out:
+ return rc;
+}
+
+void __init zpci_irq_exit(void)
+{
+ unsigned int cpu;
+
+ if (irq_delivery == DIRECTED) {
+ for_each_possible_cpu(cpu) {
+ airq_iv_release(zpci_ibv[cpu]);
+ }
+ }
+ kfree(zpci_ibv);
+ if (zpci_sbv)
+ airq_iv_release(zpci_sbv);
+ unregister_adapter_interrupt(&zpci_airq);
+}