diff options
Diffstat (limited to 'arch/powerpc/sysdev/xics/ics-opal.c')
| -rw-r--r-- | arch/powerpc/sysdev/xics/ics-opal.c | 221 |
1 files changed, 221 insertions, 0 deletions
diff --git a/arch/powerpc/sysdev/xics/ics-opal.c b/arch/powerpc/sysdev/xics/ics-opal.c new file mode 100644 index 0000000000..5fe73dabab --- /dev/null +++ b/arch/powerpc/sysdev/xics/ics-opal.c @@ -0,0 +1,221 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * ICS backend for OPAL managed interrupts. + * + * Copyright 2011 IBM Corp. + */ + +#undef DEBUG + +#include <linux/types.h> +#include <linux/kernel.h> +#include <linux/irq.h> +#include <linux/smp.h> +#include <linux/interrupt.h> +#include <linux/init.h> +#include <linux/cpu.h> +#include <linux/of.h> +#include <linux/spinlock.h> +#include <linux/msi.h> + +#include <asm/smp.h> +#include <asm/machdep.h> +#include <asm/irq.h> +#include <asm/errno.h> +#include <asm/xics.h> +#include <asm/opal.h> +#include <asm/firmware.h> + +static int ics_opal_mangle_server(int server) +{ + /* No link for now */ + return server << 2; +} + +static int ics_opal_unmangle_server(int server) +{ + /* No link for now */ + return server >> 2; +} + +static void ics_opal_unmask_irq(struct irq_data *d) +{ + unsigned int hw_irq = (unsigned int)irqd_to_hwirq(d); + int64_t rc; + int server; + + pr_devel("ics-hal: unmask virq %d [hw 0x%x]\n", d->irq, hw_irq); + + if (hw_irq == XICS_IPI || hw_irq == XICS_IRQ_SPURIOUS) + return; + + server = xics_get_irq_server(d->irq, irq_data_get_affinity_mask(d), 0); + server = ics_opal_mangle_server(server); + + rc = opal_set_xive(hw_irq, server, DEFAULT_PRIORITY); + if (rc != OPAL_SUCCESS) + pr_err("%s: opal_set_xive(irq=%d [hw 0x%x] server=%x)" + " error %lld\n", + __func__, d->irq, hw_irq, server, rc); +} + +static unsigned int ics_opal_startup(struct irq_data *d) +{ + ics_opal_unmask_irq(d); + return 0; +} + +static void ics_opal_mask_real_irq(unsigned int hw_irq) +{ + int server = ics_opal_mangle_server(xics_default_server); + int64_t rc; + + if (hw_irq == XICS_IPI) + return; + + /* Have to set XIVE to 0xff to be able to remove a slot */ + rc = opal_set_xive(hw_irq, server, 0xff); + if (rc != OPAL_SUCCESS) + pr_err("%s: opal_set_xive(0xff) irq=%u returned %lld\n", + __func__, hw_irq, rc); +} + +static void ics_opal_mask_irq(struct irq_data *d) +{ + unsigned int hw_irq = (unsigned int)irqd_to_hwirq(d); + + pr_devel("ics-hal: mask virq %d [hw 0x%x]\n", d->irq, hw_irq); + + if (hw_irq == XICS_IPI || hw_irq == XICS_IRQ_SPURIOUS) + return; + ics_opal_mask_real_irq(hw_irq); +} + +static int ics_opal_set_affinity(struct irq_data *d, + const struct cpumask *cpumask, + bool force) +{ + unsigned int hw_irq = (unsigned int)irqd_to_hwirq(d); + __be16 oserver; + int16_t server; + int8_t priority; + int64_t rc; + int wanted_server; + + if (hw_irq == XICS_IPI || hw_irq == XICS_IRQ_SPURIOUS) + return -1; + + rc = opal_get_xive(hw_irq, &oserver, &priority); + if (rc != OPAL_SUCCESS) { + pr_err("%s: opal_get_xive(irq=%d [hw 0x%x]) error %lld\n", + __func__, d->irq, hw_irq, rc); + return -1; + } + + wanted_server = xics_get_irq_server(d->irq, cpumask, 1); + if (wanted_server < 0) { + pr_warn("%s: No online cpus in the mask %*pb for irq %d\n", + __func__, cpumask_pr_args(cpumask), d->irq); + return -1; + } + server = ics_opal_mangle_server(wanted_server); + + pr_debug("ics-hal: set-affinity irq %d [hw 0x%x] server: 0x%x/0x%x\n", + d->irq, hw_irq, wanted_server, server); + + rc = opal_set_xive(hw_irq, server, priority); + if (rc != OPAL_SUCCESS) { + pr_err("%s: opal_set_xive(irq=%d [hw 0x%x] server=%x)" + " error %lld\n", + __func__, d->irq, hw_irq, server, rc); + return -1; + } + return IRQ_SET_MASK_OK; +} + +static struct irq_chip ics_opal_irq_chip = { + .name = "OPAL ICS", + .irq_startup = ics_opal_startup, + .irq_mask = ics_opal_mask_irq, + .irq_unmask = ics_opal_unmask_irq, + .irq_eoi = NULL, /* Patched at init time */ + .irq_set_affinity = ics_opal_set_affinity, + .irq_set_type = xics_set_irq_type, + .irq_retrigger = xics_retrigger, +}; + +static int ics_opal_host_match(struct ics *ics, struct device_node *node) +{ + return 1; +} + +static int ics_opal_check(struct ics *ics, unsigned int hw_irq) +{ + int64_t rc; + __be16 server; + int8_t priority; + + if (WARN_ON(hw_irq == XICS_IPI || hw_irq == XICS_IRQ_SPURIOUS)) + return -EINVAL; + + /* Check if HAL knows about this interrupt */ + rc = opal_get_xive(hw_irq, &server, &priority); + if (rc != OPAL_SUCCESS) + return -ENXIO; + + return 0; +} + +static void ics_opal_mask_unknown(struct ics *ics, unsigned long vec) +{ + int64_t rc; + __be16 server; + int8_t priority; + + /* Check if HAL knows about this interrupt */ + rc = opal_get_xive(vec, &server, &priority); + if (rc != OPAL_SUCCESS) + return; + + ics_opal_mask_real_irq(vec); +} + +static long ics_opal_get_server(struct ics *ics, unsigned long vec) +{ + int64_t rc; + __be16 server; + int8_t priority; + + /* Check if HAL knows about this interrupt */ + rc = opal_get_xive(vec, &server, &priority); + if (rc != OPAL_SUCCESS) + return -1; + return ics_opal_unmangle_server(be16_to_cpu(server)); +} + +/* Only one global & state struct ics */ +static struct ics ics_hal = { + .check = ics_opal_check, + .mask_unknown = ics_opal_mask_unknown, + .get_server = ics_opal_get_server, + .host_match = ics_opal_host_match, + .chip = &ics_opal_irq_chip, +}; + +int __init ics_opal_init(void) +{ + if (!firmware_has_feature(FW_FEATURE_OPAL)) + return -ENODEV; + + /* We need to patch our irq chip's EOI to point to the + * right ICP + */ + ics_opal_irq_chip.irq_eoi = icp_ops->eoi; + + /* Register ourselves */ + xics_register_ics(&ics_hal); + + pr_info("ICS OPAL backend registered\n"); + + return 0; +} |