[PATCH 02/10] powerpc/xive: guest exploitation of the XIVE interrupt controller
David Gibson
david at gibson.dropbear.id.au
Wed Aug 9 13:53:06 AEST 2017
On Tue, Aug 08, 2017 at 10:56:12AM +0200, Cédric Le Goater wrote:
> This is the framework for using XIVE in a PowerVM guest. The support
> is very similar to the native one in a much simpler form.
>
> Instead of OPAL calls, a set of Hypervisors call are used to configure
> the interrupt sources and the event/notification queues of the guest:
>
> - H_INT_GET_SOURCE_INFO
>
> used to obtain the address of the MMIO page of the Event State
> Buffer (PQ bits) entry associated with the source.
>
> - H_INT_SET_SOURCE_CONFIG
>
> assigns a source to a "target".
>
> - H_INT_GET_SOURCE_CONFIG
>
> determines to which "target" and "priority" is assigned to a source
>
> - H_INT_GET_QUEUE_INFO
>
> returns the address of the notification management page associated
> with the specified "target" and "priority".
>
> - H_INT_SET_QUEUE_CONFIG
>
> sets or resets the event queue for a given "target" and "priority".
> It is also used to set the notification config associated with the
> queue, only unconditional notification for the moment. Reset is
> performed with a queue size of 0 and queueing is disabled in that
> case.
>
> - H_INT_GET_QUEUE_CONFIG
>
> returns the queue settings for a given "target" and "priority".
>
> - H_INT_RESET
>
> resets all of the partition's interrupt exploitation structures to
> their initial state, losing all configuration set via the hcalls
> H_INT_SET_SOURCE_CONFIG and H_INT_SET_QUEUE_CONFIG.
>
> - H_INT_SYNC
>
> issue a synchronisation on a source to make sure sure all
> notifications have reached their queue.
>
> As for XICS, the XIVE interface for the guest is described in the
> device tree under the interrupt controller node. A couple of new
> properties are specific to XIVE :
>
> - "reg"
>
> contains the base address and size of the thread interrupt
> managnement areas (TIMA) for the user level for the OS level. Only
> the OS level is taken into account.
>
> - "ibm,xive-eq-sizes"
>
> the size of the event queues.
>
> - "ibm,xive-lisn-ranges"
>
> the interrupt numbers ranges assigned to the guest. These are
> allocated using a simple bitmap.
>
> Tested with a QEMU XIVE model for pseries and with the Power
> hypervisor
>
> Signed-off-by: Cédric Le Goater <clg at kaod.org>
I don't know XIVE well enough to review in detail, but I've made some
comments based on general knowledge.
> ---
> arch/powerpc/include/asm/hvcall.h | 13 +-
> arch/powerpc/include/asm/xive.h | 2 +
> arch/powerpc/platforms/pseries/Kconfig | 1 +
> arch/powerpc/platforms/pseries/hotplug-cpu.c | 10 +-
> arch/powerpc/platforms/pseries/kexec.c | 6 +-
> arch/powerpc/platforms/pseries/setup.c | 8 +-
> arch/powerpc/platforms/pseries/smp.c | 32 +-
> arch/powerpc/sysdev/xive/Kconfig | 5 +
> arch/powerpc/sysdev/xive/Makefile | 1 +
> arch/powerpc/sysdev/xive/spapr.c | 554 +++++++++++++++++++++++++++
> 10 files changed, 619 insertions(+), 13 deletions(-)
> create mode 100644 arch/powerpc/sysdev/xive/spapr.c
>
> diff --git a/arch/powerpc/include/asm/hvcall.h b/arch/powerpc/include/asm/hvcall.h
> index 57d38b504ff7..3d34dc0869f6 100644
> --- a/arch/powerpc/include/asm/hvcall.h
> +++ b/arch/powerpc/include/asm/hvcall.h
> @@ -280,7 +280,18 @@
> #define H_RESIZE_HPT_COMMIT 0x370
> #define H_REGISTER_PROC_TBL 0x37C
> #define H_SIGNAL_SYS_RESET 0x380
> -#define MAX_HCALL_OPCODE H_SIGNAL_SYS_RESET
> +#define H_INT_GET_SOURCE_INFO 0x3A8
> +#define H_INT_SET_SOURCE_CONFIG 0x3AC
> +#define H_INT_GET_SOURCE_CONFIG 0x3B0
> +#define H_INT_GET_QUEUE_INFO 0x3B4
> +#define H_INT_SET_QUEUE_CONFIG 0x3B8
> +#define H_INT_GET_QUEUE_CONFIG 0x3BC
> +#define H_INT_SET_OS_REPORTING_LINE 0x3C0
> +#define H_INT_GET_OS_REPORTING_LINE 0x3C4
> +#define H_INT_ESB 0x3C8
> +#define H_INT_SYNC 0x3CC
> +#define H_INT_RESET 0x3D0
> +#define MAX_HCALL_OPCODE H_INT_RESET
>
> /* H_VIOCTL functions */
> #define H_GET_VIOA_DUMP_SIZE 0x01
> diff --git a/arch/powerpc/include/asm/xive.h b/arch/powerpc/include/asm/xive.h
> index c23ff4389ca2..1deb10032d61 100644
> --- a/arch/powerpc/include/asm/xive.h
> +++ b/arch/powerpc/include/asm/xive.h
> @@ -110,6 +110,7 @@ extern bool __xive_enabled;
>
> static inline bool xive_enabled(void) { return __xive_enabled; }
>
> +extern bool xive_spapr_init(void);
> extern bool xive_native_init(void);
> extern void xive_smp_probe(void);
> extern int xive_smp_prepare_cpu(unsigned int cpu);
> @@ -147,6 +148,7 @@ extern int xive_native_get_vp_info(u32 vp_id, u32 *out_cam_id, u32 *out_chip_id)
>
> static inline bool xive_enabled(void) { return false; }
>
> +static inline bool xive_spapr_init(void) { return false; }
> static inline bool xive_native_init(void) { return false; }
> static inline void xive_smp_probe(void) { }
> extern inline int xive_smp_prepare_cpu(unsigned int cpu) { return -EINVAL; }
> diff --git a/arch/powerpc/platforms/pseries/Kconfig b/arch/powerpc/platforms/pseries/Kconfig
> index 3a6dfd14f64b..71dd69d9ec64 100644
> --- a/arch/powerpc/platforms/pseries/Kconfig
> +++ b/arch/powerpc/platforms/pseries/Kconfig
> @@ -7,6 +7,7 @@ config PPC_PSERIES
> select PCI
> select PCI_MSI
> select PPC_XICS
> + select PPC_XIVE_SPAPR
> select PPC_ICP_NATIVE
> select PPC_ICP_HV
> select PPC_ICS_RTAS
> diff --git a/arch/powerpc/platforms/pseries/hotplug-cpu.c b/arch/powerpc/platforms/pseries/hotplug-cpu.c
> index 6afd1efd3633..de0a5c1d7b29 100644
> --- a/arch/powerpc/platforms/pseries/hotplug-cpu.c
> +++ b/arch/powerpc/platforms/pseries/hotplug-cpu.c
> @@ -34,6 +34,7 @@
> #include <asm/machdep.h>
> #include <asm/vdso_datapage.h>
> #include <asm/xics.h>
> +#include <asm/xive.h>
> #include <asm/plpar_wrappers.h>
>
> #include "pseries.h"
> @@ -109,7 +110,9 @@ static void pseries_mach_cpu_die(void)
>
> local_irq_disable();
> idle_task_exit();
> - xics_teardown_cpu();
> + /* Nothing TODO for xive ? */;
You have a XIVE teardown_cpu() method below - should you be calling
that here, even though it's a no-op for now?
> + if (!xive_enabled())
> + xics_teardown_cpu();
>
> if (get_preferred_offline_state(cpu) == CPU_STATE_INACTIVE) {
> set_cpu_current_state(cpu, CPU_STATE_INACTIVE);
> @@ -174,7 +177,10 @@ static int pseries_cpu_disable(void)
> boot_cpuid = cpumask_any(cpu_online_mask);
>
> /* FIXME: abstract this to not be platform specific later on */
> - xics_migrate_irqs_away();
> + if (xive_enabled())
> + xive_smp_disable_cpu();
> + else
> + xics_migrate_irqs_away();
> return 0;
> }
>
> diff --git a/arch/powerpc/platforms/pseries/kexec.c b/arch/powerpc/platforms/pseries/kexec.c
> index 6681ac97fb18..eeb13429d685 100644
> --- a/arch/powerpc/platforms/pseries/kexec.c
> +++ b/arch/powerpc/platforms/pseries/kexec.c
> @@ -15,6 +15,7 @@
> #include <asm/firmware.h>
> #include <asm/kexec.h>
> #include <asm/xics.h>
> +#include <asm/xive.h>
> #include <asm/smp.h>
> #include <asm/plpar_wrappers.h>
>
> @@ -51,5 +52,8 @@ void pseries_kexec_cpu_down(int crash_shutdown, int secondary)
> }
> }
>
> - xics_kexec_teardown_cpu(secondary);
> + if (xive_enabled())
> + xive_kexec_teardown_cpu(secondary);
> + else
> + xics_kexec_teardown_cpu(secondary);
> }
> diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
> index b5d86426e97b..a8531e012658 100644
> --- a/arch/powerpc/platforms/pseries/setup.c
> +++ b/arch/powerpc/platforms/pseries/setup.c
> @@ -57,6 +57,7 @@
> #include <asm/nvram.h>
> #include <asm/pmc.h>
> #include <asm/xics.h>
> +#include <asm/xive.h>
> #include <asm/ppc-pci.h>
> #include <asm/i8259.h>
> #include <asm/udbg.h>
> @@ -176,8 +177,11 @@ static void __init pseries_setup_i8259_cascade(void)
>
> static void __init pseries_init_irq(void)
> {
> - xics_init();
> - pseries_setup_i8259_cascade();
> + /* Try using a XIVE if available, otherwise use a XICS */
> + if (!xive_spapr_init()) {
> + xics_init();
> + pseries_setup_i8259_cascade();
> + }
> }
>
> static void pseries_lpar_enable_pmcs(void)
> diff --git a/arch/powerpc/platforms/pseries/smp.c b/arch/powerpc/platforms/pseries/smp.c
> index 24785f63fb40..244bb9974963 100644
> --- a/arch/powerpc/platforms/pseries/smp.c
> +++ b/arch/powerpc/platforms/pseries/smp.c
> @@ -41,6 +41,7 @@
> #include <asm/vdso_datapage.h>
> #include <asm/cputhreads.h>
> #include <asm/xics.h>
> +#include <asm/xive.h>
> #include <asm/dbell.h>
> #include <asm/plpar_wrappers.h>
> #include <asm/code-patching.h>
> @@ -136,7 +137,9 @@ static inline int smp_startup_cpu(unsigned int lcpu)
>
> static void smp_setup_cpu(int cpu)
> {
> - if (cpu != boot_cpuid)
> + if (xive_enabled())
> + xive_smp_setup_cpu();
> + else if (cpu != boot_cpuid)
> xics_setup_cpu();
>
> if (firmware_has_feature(FW_FEATURE_SPLPAR))
> @@ -181,13 +184,22 @@ static int smp_pSeries_kick_cpu(int nr)
> return 0;
> }
>
> +static int pseries_smp_prepare_cpu(int cpu)
> +{
> + if (xive_enabled())
> + return xive_smp_prepare_cpu(cpu);
> + return 0;
> +}
> +
> +/* Cause IPI as setup by the interrupt controller (xics or xive) */
> +static void (*ic_cause_ipi)(int cpu);
> +
> static void smp_pseries_cause_ipi(int cpu)
> {
> - /* POWER9 should not use this handler */
> if (doorbell_try_core_ipi(cpu))
> return;
>
> - icp_ops->cause_ipi(cpu);
> + ic_cause_ipi(cpu);
Wouldn't it make more sense to change smp_ops->cause_ipi, rather than
having a double indirection through smp_ops, then the ic_cause_ipi
global?
> }
>
> static int pseries_cause_nmi_ipi(int cpu)
> @@ -213,12 +225,17 @@ static int pseries_cause_nmi_ipi(int cpu)
>
> static __init void pSeries_smp_probe(void)
> {
> - xics_smp_probe();
> + if (xive_enabled())
> + xive_smp_probe();
> + else
> + xics_smp_probe();
> +
> + if (cpu_has_feature(CPU_FTR_DBELL)) {
> + ic_cause_ipi = smp_ops->cause_ipi;
> + WARN_ON(!ic_cause_ipi);
>
> - if (cpu_has_feature(CPU_FTR_DBELL))
> smp_ops->cause_ipi = smp_pseries_cause_ipi;
> - else
> - smp_ops->cause_ipi = icp_ops->cause_ipi;
> + }
> }
>
> static struct smp_ops_t pseries_smp_ops = {
> @@ -226,6 +243,7 @@ static struct smp_ops_t pseries_smp_ops = {
> .cause_ipi = NULL, /* Filled at runtime by pSeries_smp_probe() */
> .cause_nmi_ipi = pseries_cause_nmi_ipi,
> .probe = pSeries_smp_probe,
> + .prepare_cpu = pseries_smp_prepare_cpu,
> .kick_cpu = smp_pSeries_kick_cpu,
> .setup_cpu = smp_setup_cpu,
> .cpu_bootable = smp_generic_cpu_bootable,
> diff --git a/arch/powerpc/sysdev/xive/Kconfig b/arch/powerpc/sysdev/xive/Kconfig
> index 12ccd7373d2f..3e3e25b5e30d 100644
> --- a/arch/powerpc/sysdev/xive/Kconfig
> +++ b/arch/powerpc/sysdev/xive/Kconfig
> @@ -9,3 +9,8 @@ config PPC_XIVE_NATIVE
> default n
> select PPC_XIVE
> depends on PPC_POWERNV
> +
> +config PPC_XIVE_SPAPR
> + bool
> + default n
> + select PPC_XIVE
> diff --git a/arch/powerpc/sysdev/xive/Makefile b/arch/powerpc/sysdev/xive/Makefile
> index 3fab303fc169..536d6e5706e3 100644
> --- a/arch/powerpc/sysdev/xive/Makefile
> +++ b/arch/powerpc/sysdev/xive/Makefile
> @@ -2,3 +2,4 @@ subdir-ccflags-$(CONFIG_PPC_WERROR) := -Werror
>
> obj-y += common.o
> obj-$(CONFIG_PPC_XIVE_NATIVE) += native.o
> +obj-$(CONFIG_PPC_XIVE_SPAPR) += spapr.o
> diff --git a/arch/powerpc/sysdev/xive/spapr.c b/arch/powerpc/sysdev/xive/spapr.c
> new file mode 100644
> index 000000000000..a3668815d5c1
> --- /dev/null
> +++ b/arch/powerpc/sysdev/xive/spapr.c
> @@ -0,0 +1,554 @@
> +/*
> + * 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 <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;
> + }
> + }
> +}
> +
> +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;
> +
> + rc = plpar_hcall(H_INT_GET_SOURCE_INFO, retbuf, flags, lisn);
> + 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);
> +
> +
> + rc = plpar_hcall_norets(H_INT_SET_SOURCE_CONFIG, flags, lisn,
> + target, prio, sw_irq);
> + if (rc) {
> + pr_err("H_INT_SET_SOURCE_CONFIG lisn=%ld failed %ld\n",
> + lisn, 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;
> +
> + rc = plpar_hcall(H_INT_GET_QUEUE_INFO, retbuf, flags, target, priority);
> + 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);
> +
> + rc = plpar_hcall_norets(H_INT_SET_QUEUE_CONFIG, flags, target,
> + priority, qpage, qsize);
> + 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)
> +{
> + long rc;
> +
> + rc = plpar_hcall_norets(H_INT_SYNC, flags);
> + if (rc) {
> + pr_err("H_INT_SYNC returned %ld\n", rc);
> + return rc;
> + }
> +
> + return 0;
> +}
> +
> +#define XIVE_SRC_H_INT_ESB (1ull << (63 - 60)) /* TODO */
> +#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_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;
> +
> + /*
> + * 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;
> +
> + 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 prio %d\n", rc, 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 prio %d\n", rc, 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];
> + unsigned int alloc_order;
> + struct page *pages;
> + __be32 *qpage;
> +
> + alloc_order = (xive_queue_shift > PAGE_SHIFT) ?
> + (xive_queue_shift - PAGE_SHIFT) : 0;
> + pages = alloc_pages_node(cpu_to_node(cpu), GFP_KERNEL, alloc_order);
> + if (!pages)
> + return -ENOMEM;
> + qpage = (__be32 *)page_address(pages);
> + memset(qpage, 0, 1 << xive_queue_shift);
> +
> + return xive_spapr_configure_queue(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;
> +
> + rc = plpar_int_set_queue_config(0, cpu, prio, 0, 0);
> + if (rc)
> + pr_err("Error %ld setting queue for prio %d\n", rc, prio);
> +
> + alloc_order = (xive_queue_shift > PAGE_SHIFT) ?
> + (xive_queue_shift - PAGE_SHIFT) : 0;
Maybe a helper inline for this calculation, since it's used in both
setup_queue() and cleanup_queue?
> + free_pages((unsigned long)q->qpage, alloc_order);
> + q->qpage = NULL;
> +}
> +
> +static bool xive_spapr_match(struct device_node *node)
> +{
> + 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)
> +{
> + xive_irq_bitmap_free(xc->hw_ipi);
> +}
> +#endif /* CONFIG_SMP */
> +
> +static void xive_spapr_shutdown(void)
> +{
> + long rc;
> +
> + rc = plpar_hcall_norets(H_INT_RESET, 0);
> + if (rc)
> + pr_err("H_INT_RESET failed %ld\n", rc);
> +}
> +
> +static void xive_spapr_update_pending(struct xive_cpu *xc)
> +{
> + u8 nsr, cppr;
> + u16 ack;
> +
> + /* Perform the acknowledge hypervisor to register cycle */
> + ack = be16_to_cpu(__raw_readw(xive_tima + TM_SPC_ACK_OS_REG));
Why do you need the raw_readw() + be16_to_cpu + mb, rather than one of
the higher level IO helpers?
> + /* Synchronize subsequent queue accesses */
> + mb();
> +
> + /*
> + * Grab the CPPR and the "NSR" field which indicates the source
> + * of the hypervisor 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 */;
> +}
Do you really want empty stub functions, or would it be better to have
the method caller check for NULL in the ops structure?
> +
> +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);
> +}
> +
> +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,
> +#ifdef CONFIG_SMP
> + .get_ipi = xive_spapr_get_ipi,
> + .put_ipi = xive_spapr_put_ipi,
> +#endif /* CONFIG_SMP */
> + .name = "spapr",
> +};
> +
> +bool xive_spapr_init(void)
> +{
> + struct device_node *np;
> + struct resource r;
> + void __iomem *tima;
> + struct property *prop;
> + u8 max_prio = 7;
> + 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;
> + }
> +
> + /* 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;
> +}
--
David Gibson | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_
| _way_ _around_!
http://www.ozlabs.org/~dgibson
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