diff options
Diffstat (limited to 'arch/powerpc/sysdev/xive/spapr.c')
-rw-r--r-- | arch/powerpc/sysdev/xive/spapr.c | 740 |
1 files changed, 740 insertions, 0 deletions
diff --git a/arch/powerpc/sysdev/xive/spapr.c b/arch/powerpc/sysdev/xive/spapr.c new file mode 100644 index 000000000..5566bbc86 --- /dev/null +++ b/arch/powerpc/sysdev/xive/spapr.c @@ -0,0 +1,740 @@ +/* + * Copyright 2016,2017 IBM Corporation. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#define pr_fmt(fmt) "xive: " fmt + +#include <linux/types.h> +#include <linux/irq.h> +#include <linux/smp.h> +#include <linux/interrupt.h> +#include <linux/init.h> +#include <linux/of.h> +#include <linux/slab.h> +#include <linux/spinlock.h> +#include <linux/cpumask.h> +#include <linux/mm.h> +#include <linux/delay.h> + +#include <asm/prom.h> +#include <asm/io.h> +#include <asm/smp.h> +#include <asm/irq.h> +#include <asm/errno.h> +#include <asm/xive.h> +#include <asm/xive-regs.h> +#include <asm/hvcall.h> + +#include "xive-internal.h" + +static u32 xive_queue_shift; + +struct xive_irq_bitmap { + unsigned long *bitmap; + unsigned int base; + unsigned int count; + spinlock_t lock; + struct list_head list; +}; + +static LIST_HEAD(xive_irq_bitmaps); + +static int xive_irq_bitmap_add(int base, int count) +{ + struct xive_irq_bitmap *xibm; + + xibm = kzalloc(sizeof(*xibm), GFP_ATOMIC); + if (!xibm) + return -ENOMEM; + + spin_lock_init(&xibm->lock); + xibm->base = base; + xibm->count = count; + xibm->bitmap = kzalloc(xibm->count, GFP_KERNEL); + list_add(&xibm->list, &xive_irq_bitmaps); + + pr_info("Using IRQ range [%x-%x]", xibm->base, + xibm->base + xibm->count - 1); + return 0; +} + +static int __xive_irq_bitmap_alloc(struct xive_irq_bitmap *xibm) +{ + int irq; + + irq = find_first_zero_bit(xibm->bitmap, xibm->count); + if (irq != xibm->count) { + set_bit(irq, xibm->bitmap); + irq += xibm->base; + } else { + irq = -ENOMEM; + } + + return irq; +} + +static int xive_irq_bitmap_alloc(void) +{ + struct xive_irq_bitmap *xibm; + unsigned long flags; + int irq = -ENOENT; + + list_for_each_entry(xibm, &xive_irq_bitmaps, list) { + spin_lock_irqsave(&xibm->lock, flags); + irq = __xive_irq_bitmap_alloc(xibm); + spin_unlock_irqrestore(&xibm->lock, flags); + if (irq >= 0) + break; + } + return irq; +} + +static void xive_irq_bitmap_free(int irq) +{ + unsigned long flags; + struct xive_irq_bitmap *xibm; + + list_for_each_entry(xibm, &xive_irq_bitmaps, list) { + if ((irq >= xibm->base) && (irq < xibm->base + xibm->count)) { + spin_lock_irqsave(&xibm->lock, flags); + clear_bit(irq - xibm->base, xibm->bitmap); + spin_unlock_irqrestore(&xibm->lock, flags); + break; + } + } +} + + +/* Based on the similar routines in RTAS */ +static unsigned int plpar_busy_delay_time(long rc) +{ + unsigned int ms = 0; + + if (H_IS_LONG_BUSY(rc)) { + ms = get_longbusy_msecs(rc); + } else if (rc == H_BUSY) { + ms = 10; /* seems appropriate for XIVE hcalls */ + } + + return ms; +} + +static unsigned int plpar_busy_delay(int rc) +{ + unsigned int ms; + + ms = plpar_busy_delay_time(rc); + if (ms) + mdelay(ms); + + return ms; +} + +/* + * Note: this call has a partition wide scope and can take a while to + * complete. If it returns H_LONG_BUSY_* it should be retried + * periodically. + */ +static long plpar_int_reset(unsigned long flags) +{ + long rc; + + do { + rc = plpar_hcall_norets(H_INT_RESET, flags); + } while (plpar_busy_delay(rc)); + + if (rc) + pr_err("H_INT_RESET failed %ld\n", rc); + + return rc; +} + +static long plpar_int_get_source_info(unsigned long flags, + unsigned long lisn, + unsigned long *src_flags, + unsigned long *eoi_page, + unsigned long *trig_page, + unsigned long *esb_shift) +{ + unsigned long retbuf[PLPAR_HCALL_BUFSIZE]; + long rc; + + do { + rc = plpar_hcall(H_INT_GET_SOURCE_INFO, retbuf, flags, lisn); + } while (plpar_busy_delay(rc)); + + if (rc) { + pr_err("H_INT_GET_SOURCE_INFO lisn=%ld failed %ld\n", lisn, rc); + return rc; + } + + *src_flags = retbuf[0]; + *eoi_page = retbuf[1]; + *trig_page = retbuf[2]; + *esb_shift = retbuf[3]; + + pr_devel("H_INT_GET_SOURCE_INFO flags=%lx eoi=%lx trig=%lx shift=%lx\n", + retbuf[0], retbuf[1], retbuf[2], retbuf[3]); + + return 0; +} + +#define XIVE_SRC_SET_EISN (1ull << (63 - 62)) +#define XIVE_SRC_MASK (1ull << (63 - 63)) /* unused */ + +static long plpar_int_set_source_config(unsigned long flags, + unsigned long lisn, + unsigned long target, + unsigned long prio, + unsigned long sw_irq) +{ + long rc; + + + pr_devel("H_INT_SET_SOURCE_CONFIG flags=%lx lisn=%lx target=%lx prio=%lx sw_irq=%lx\n", + flags, lisn, target, prio, sw_irq); + + + do { + rc = plpar_hcall_norets(H_INT_SET_SOURCE_CONFIG, flags, lisn, + target, prio, sw_irq); + } while (plpar_busy_delay(rc)); + + if (rc) { + pr_err("H_INT_SET_SOURCE_CONFIG lisn=%ld target=%lx prio=%lx failed %ld\n", + lisn, target, prio, rc); + return rc; + } + + return 0; +} + +static long plpar_int_get_queue_info(unsigned long flags, + unsigned long target, + unsigned long priority, + unsigned long *esn_page, + unsigned long *esn_size) +{ + unsigned long retbuf[PLPAR_HCALL_BUFSIZE]; + long rc; + + do { + rc = plpar_hcall(H_INT_GET_QUEUE_INFO, retbuf, flags, target, + priority); + } while (plpar_busy_delay(rc)); + + if (rc) { + pr_err("H_INT_GET_QUEUE_INFO cpu=%ld prio=%ld failed %ld\n", + target, priority, rc); + return rc; + } + + *esn_page = retbuf[0]; + *esn_size = retbuf[1]; + + pr_devel("H_INT_GET_QUEUE_INFO page=%lx size=%lx\n", + retbuf[0], retbuf[1]); + + return 0; +} + +#define XIVE_EQ_ALWAYS_NOTIFY (1ull << (63 - 63)) + +static long plpar_int_set_queue_config(unsigned long flags, + unsigned long target, + unsigned long priority, + unsigned long qpage, + unsigned long qsize) +{ + long rc; + + pr_devel("H_INT_SET_QUEUE_CONFIG flags=%lx target=%lx priority=%lx qpage=%lx qsize=%lx\n", + flags, target, priority, qpage, qsize); + + do { + rc = plpar_hcall_norets(H_INT_SET_QUEUE_CONFIG, flags, target, + priority, qpage, qsize); + } while (plpar_busy_delay(rc)); + + if (rc) { + pr_err("H_INT_SET_QUEUE_CONFIG cpu=%ld prio=%ld qpage=%lx returned %ld\n", + target, priority, qpage, rc); + return rc; + } + + return 0; +} + +static long plpar_int_sync(unsigned long flags, unsigned long lisn) +{ + long rc; + + do { + rc = plpar_hcall_norets(H_INT_SYNC, flags, lisn); + } while (plpar_busy_delay(rc)); + + if (rc) { + pr_err("H_INT_SYNC lisn=%ld returned %ld\n", lisn, rc); + return rc; + } + + return 0; +} + +#define XIVE_ESB_FLAG_STORE (1ull << (63 - 63)) + +static long plpar_int_esb(unsigned long flags, + unsigned long lisn, + unsigned long offset, + unsigned long in_data, + unsigned long *out_data) +{ + unsigned long retbuf[PLPAR_HCALL_BUFSIZE]; + long rc; + + pr_devel("H_INT_ESB flags=%lx lisn=%lx offset=%lx in=%lx\n", + flags, lisn, offset, in_data); + + do { + rc = plpar_hcall(H_INT_ESB, retbuf, flags, lisn, offset, + in_data); + } while (plpar_busy_delay(rc)); + + if (rc) { + pr_err("H_INT_ESB lisn=%ld offset=%ld returned %ld\n", + lisn, offset, rc); + return rc; + } + + *out_data = retbuf[0]; + + return 0; +} + +static u64 xive_spapr_esb_rw(u32 lisn, u32 offset, u64 data, bool write) +{ + unsigned long read_data; + long rc; + + rc = plpar_int_esb(write ? XIVE_ESB_FLAG_STORE : 0, + lisn, offset, data, &read_data); + if (rc) + return -1; + + return write ? 0 : read_data; +} + +#define XIVE_SRC_H_INT_ESB (1ull << (63 - 60)) +#define XIVE_SRC_LSI (1ull << (63 - 61)) +#define XIVE_SRC_TRIGGER (1ull << (63 - 62)) +#define XIVE_SRC_STORE_EOI (1ull << (63 - 63)) + +static int xive_spapr_populate_irq_data(u32 hw_irq, struct xive_irq_data *data) +{ + long rc; + unsigned long flags; + unsigned long eoi_page; + unsigned long trig_page; + unsigned long esb_shift; + + memset(data, 0, sizeof(*data)); + + rc = plpar_int_get_source_info(0, hw_irq, &flags, &eoi_page, &trig_page, + &esb_shift); + if (rc) + return -EINVAL; + + if (flags & XIVE_SRC_H_INT_ESB) + data->flags |= XIVE_IRQ_FLAG_H_INT_ESB; + if (flags & XIVE_SRC_STORE_EOI) + data->flags |= XIVE_IRQ_FLAG_STORE_EOI; + if (flags & XIVE_SRC_LSI) + data->flags |= XIVE_IRQ_FLAG_LSI; + data->eoi_page = eoi_page; + data->esb_shift = esb_shift; + data->trig_page = trig_page; + + data->hw_irq = hw_irq; + + /* + * No chip-id for the sPAPR backend. This has an impact how we + * pick a target. See xive_pick_irq_target(). + */ + data->src_chip = XIVE_INVALID_CHIP_ID; + + /* + * When the H_INT_ESB flag is set, the H_INT_ESB hcall should + * be used for interrupt management. Skip the remapping of the + * ESB pages which are not available. + */ + if (data->flags & XIVE_IRQ_FLAG_H_INT_ESB) + return 0; + + data->eoi_mmio = ioremap(data->eoi_page, 1u << data->esb_shift); + if (!data->eoi_mmio) { + pr_err("Failed to map EOI page for irq 0x%x\n", hw_irq); + return -ENOMEM; + } + + /* Full function page supports trigger */ + if (flags & XIVE_SRC_TRIGGER) { + data->trig_mmio = data->eoi_mmio; + return 0; + } + + data->trig_mmio = ioremap(data->trig_page, 1u << data->esb_shift); + if (!data->trig_mmio) { + pr_err("Failed to map trigger page for irq 0x%x\n", hw_irq); + return -ENOMEM; + } + return 0; +} + +static int xive_spapr_configure_irq(u32 hw_irq, u32 target, u8 prio, u32 sw_irq) +{ + long rc; + + rc = plpar_int_set_source_config(XIVE_SRC_SET_EISN, hw_irq, target, + prio, sw_irq); + + return rc == 0 ? 0 : -ENXIO; +} + +/* This can be called multiple time to change a queue configuration */ +static int xive_spapr_configure_queue(u32 target, struct xive_q *q, u8 prio, + __be32 *qpage, u32 order) +{ + s64 rc = 0; + unsigned long esn_page; + unsigned long esn_size; + u64 flags, qpage_phys; + + /* If there's an actual queue page, clean it */ + if (order) { + if (WARN_ON(!qpage)) + return -EINVAL; + qpage_phys = __pa(qpage); + } else { + qpage_phys = 0; + } + + /* Initialize the rest of the fields */ + q->msk = order ? ((1u << (order - 2)) - 1) : 0; + q->idx = 0; + q->toggle = 0; + + rc = plpar_int_get_queue_info(0, target, prio, &esn_page, &esn_size); + if (rc) { + pr_err("Error %lld getting queue info CPU %d prio %d\n", rc, + target, prio); + rc = -EIO; + goto fail; + } + + /* TODO: add support for the notification page */ + q->eoi_phys = esn_page; + + /* Default is to always notify */ + flags = XIVE_EQ_ALWAYS_NOTIFY; + + /* Configure and enable the queue in HW */ + rc = plpar_int_set_queue_config(flags, target, prio, qpage_phys, order); + if (rc) { + pr_err("Error %lld setting queue for CPU %d prio %d\n", rc, + target, prio); + rc = -EIO; + } else { + q->qpage = qpage; + } +fail: + return rc; +} + +static int xive_spapr_setup_queue(unsigned int cpu, struct xive_cpu *xc, + u8 prio) +{ + struct xive_q *q = &xc->queue[prio]; + __be32 *qpage; + + qpage = xive_queue_page_alloc(cpu, xive_queue_shift); + if (IS_ERR(qpage)) + return PTR_ERR(qpage); + + return xive_spapr_configure_queue(get_hard_smp_processor_id(cpu), + q, prio, qpage, xive_queue_shift); +} + +static void xive_spapr_cleanup_queue(unsigned int cpu, struct xive_cpu *xc, + u8 prio) +{ + struct xive_q *q = &xc->queue[prio]; + unsigned int alloc_order; + long rc; + int hw_cpu = get_hard_smp_processor_id(cpu); + + rc = plpar_int_set_queue_config(0, hw_cpu, prio, 0, 0); + if (rc) + pr_err("Error %ld setting queue for CPU %d prio %d\n", rc, + hw_cpu, prio); + + alloc_order = xive_alloc_order(xive_queue_shift); + free_pages((unsigned long)q->qpage, alloc_order); + q->qpage = NULL; +} + +static bool xive_spapr_match(struct device_node *node) +{ + /* Ignore cascaded controllers for the moment */ + return 1; +} + +#ifdef CONFIG_SMP +static int xive_spapr_get_ipi(unsigned int cpu, struct xive_cpu *xc) +{ + int irq = xive_irq_bitmap_alloc(); + + if (irq < 0) { + pr_err("Failed to allocate IPI on CPU %d\n", cpu); + return -ENXIO; + } + + xc->hw_ipi = irq; + return 0; +} + +static void xive_spapr_put_ipi(unsigned int cpu, struct xive_cpu *xc) +{ + if (xc->hw_ipi == XIVE_BAD_IRQ) + return; + + xive_irq_bitmap_free(xc->hw_ipi); + xc->hw_ipi = XIVE_BAD_IRQ; +} +#endif /* CONFIG_SMP */ + +static void xive_spapr_shutdown(void) +{ + plpar_int_reset(0); +} + +/* + * Perform an "ack" cycle on the current thread. Grab the pending + * active priorities and update the CPPR to the most favored one. + */ +static void xive_spapr_update_pending(struct xive_cpu *xc) +{ + u8 nsr, cppr; + u16 ack; + + /* + * Perform the "Acknowledge O/S to Register" cycle. + * + * Let's speedup the access to the TIMA using the raw I/O + * accessor as we don't need the synchronisation routine of + * the higher level ones + */ + ack = be16_to_cpu(__raw_readw(xive_tima + TM_SPC_ACK_OS_REG)); + + /* Synchronize subsequent queue accesses */ + mb(); + + /* + * Grab the CPPR and the "NSR" field which indicates the source + * of the interrupt (if any) + */ + cppr = ack & 0xff; + nsr = ack >> 8; + + if (nsr & TM_QW1_NSR_EO) { + if (cppr == 0xff) + return; + /* Mark the priority pending */ + xc->pending_prio |= 1 << cppr; + + /* + * A new interrupt should never have a CPPR less favored + * than our current one. + */ + if (cppr >= xc->cppr) + pr_err("CPU %d odd ack CPPR, got %d at %d\n", + smp_processor_id(), cppr, xc->cppr); + + /* Update our idea of what the CPPR is */ + xc->cppr = cppr; + } +} + +static void xive_spapr_eoi(u32 hw_irq) +{ + /* Not used */; +} + +static void xive_spapr_setup_cpu(unsigned int cpu, struct xive_cpu *xc) +{ + /* Only some debug on the TIMA settings */ + pr_debug("(HW value: %08x %08x %08x)\n", + in_be32(xive_tima + TM_QW1_OS + TM_WORD0), + in_be32(xive_tima + TM_QW1_OS + TM_WORD1), + in_be32(xive_tima + TM_QW1_OS + TM_WORD2)); +} + +static void xive_spapr_teardown_cpu(unsigned int cpu, struct xive_cpu *xc) +{ + /* Nothing to do */; +} + +static void xive_spapr_sync_source(u32 hw_irq) +{ + /* Specs are unclear on what this is doing */ + plpar_int_sync(0, hw_irq); +} + +static const struct xive_ops xive_spapr_ops = { + .populate_irq_data = xive_spapr_populate_irq_data, + .configure_irq = xive_spapr_configure_irq, + .setup_queue = xive_spapr_setup_queue, + .cleanup_queue = xive_spapr_cleanup_queue, + .match = xive_spapr_match, + .shutdown = xive_spapr_shutdown, + .update_pending = xive_spapr_update_pending, + .eoi = xive_spapr_eoi, + .setup_cpu = xive_spapr_setup_cpu, + .teardown_cpu = xive_spapr_teardown_cpu, + .sync_source = xive_spapr_sync_source, + .esb_rw = xive_spapr_esb_rw, +#ifdef CONFIG_SMP + .get_ipi = xive_spapr_get_ipi, + .put_ipi = xive_spapr_put_ipi, +#endif /* CONFIG_SMP */ + .name = "spapr", +}; + +/* + * get max priority from "/ibm,plat-res-int-priorities" + */ +static bool xive_get_max_prio(u8 *max_prio) +{ + struct device_node *rootdn; + const __be32 *reg; + u32 len; + int prio, found; + + rootdn = of_find_node_by_path("/"); + if (!rootdn) { + pr_err("not root node found !\n"); + return false; + } + + reg = of_get_property(rootdn, "ibm,plat-res-int-priorities", &len); + if (!reg) { + pr_err("Failed to read 'ibm,plat-res-int-priorities' property\n"); + return false; + } + + if (len % (2 * sizeof(u32)) != 0) { + pr_err("invalid 'ibm,plat-res-int-priorities' property\n"); + return false; + } + + /* HW supports priorities in the range [0-7] and 0xFF is a + * wildcard priority used to mask. We scan the ranges reserved + * by the hypervisor to find the lowest priority we can use. + */ + found = 0xFF; + for (prio = 0; prio < 8; prio++) { + int reserved = 0; + int i; + + for (i = 0; i < len / (2 * sizeof(u32)); i++) { + int base = be32_to_cpu(reg[2 * i]); + int range = be32_to_cpu(reg[2 * i + 1]); + + if (prio >= base && prio < base + range) + reserved++; + } + + if (!reserved) + found = prio; + } + + if (found == 0xFF) { + pr_err("no valid priority found in 'ibm,plat-res-int-priorities'\n"); + return false; + } + + *max_prio = found; + return true; +} + +bool __init xive_spapr_init(void) +{ + struct device_node *np; + struct resource r; + void __iomem *tima; + struct property *prop; + u8 max_prio; + u32 val; + u32 len; + const __be32 *reg; + int i; + + if (xive_cmdline_disabled) + return false; + + pr_devel("%s()\n", __func__); + np = of_find_compatible_node(NULL, NULL, "ibm,power-ivpe"); + if (!np) { + pr_devel("not found !\n"); + return false; + } + pr_devel("Found %s\n", np->full_name); + + /* Resource 1 is the OS ring TIMA */ + if (of_address_to_resource(np, 1, &r)) { + pr_err("Failed to get thread mgmnt area resource\n"); + return false; + } + tima = ioremap(r.start, resource_size(&r)); + if (!tima) { + pr_err("Failed to map thread mgmnt area\n"); + return false; + } + + if (!xive_get_max_prio(&max_prio)) + return false; + + /* Feed the IRQ number allocator with the ranges given in the DT */ + reg = of_get_property(np, "ibm,xive-lisn-ranges", &len); + if (!reg) { + pr_err("Failed to read 'ibm,xive-lisn-ranges' property\n"); + return false; + } + + if (len % (2 * sizeof(u32)) != 0) { + pr_err("invalid 'ibm,xive-lisn-ranges' property\n"); + return false; + } + + for (i = 0; i < len / (2 * sizeof(u32)); i++, reg += 2) + xive_irq_bitmap_add(be32_to_cpu(reg[0]), + be32_to_cpu(reg[1])); + + /* Iterate the EQ sizes and pick one */ + of_property_for_each_u32(np, "ibm,xive-eq-sizes", prop, reg, val) { + xive_queue_shift = val; + if (val == PAGE_SHIFT) + break; + } + + /* Initialize XIVE core with our backend */ + if (!xive_core_init(&xive_spapr_ops, tima, TM_QW1_OS, max_prio)) + return false; + + pr_info("Using %dkB queues\n", 1 << (xive_queue_shift - 10)); + return true; +} |