mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-09-03 17:40:04 +00:00
![Chris Metcalf](/assets/img/avatar_default.png)
This change introduces new flags for the hv_install_context() API that passes a page table pointer to the hypervisor. Clients can explicitly request 4K, 16K, or 64K small pages when they install a new context. In practice, the page size is fixed at kernel compile time and the same size is always requested every time a new page table is installed. The <hv/hypervisor.h> header changes so that it provides more abstract macros for managing "page" things like PFNs and page tables. For example there is now a HV_DEFAULT_PAGE_SIZE_SMALL instead of the old HV_PAGE_SIZE_SMALL. The various PFN routines have been eliminated and only PA- or PTFN-based ones remain (since PTFNs are always expressed in fixed 2KB "page" size). The page-table management macros are renamed with a leading underscore and take page-size arguments with the presumption that clients will use those macros in some single place to provide the "real" macros they will use themselves. I happened to notice the old hv_set_caching() API was totally broken (it assumed 4KB pages) so I changed it so it would nominally work correctly with other page sizes. Tag modules with the page size so you can't load a module built with a conflicting page size. (And add a test for SMP while we're at it.) Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
244 lines
5.4 KiB
C
244 lines
5.4 KiB
C
/*
|
|
* Copyright 2010 Tilera Corporation. All Rights Reserved.
|
|
*
|
|
* 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, version 2.
|
|
*
|
|
* This program is distributed in the hope that it will be useful, but
|
|
* WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
|
|
* NON INFRINGEMENT. See the GNU General Public License for
|
|
* more details.
|
|
*
|
|
* TILE SMP support routines.
|
|
*/
|
|
|
|
#include <linux/smp.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/io.h>
|
|
#include <linux/irq.h>
|
|
#include <linux/module.h>
|
|
#include <asm/cacheflush.h>
|
|
|
|
HV_Topology smp_topology __write_once;
|
|
EXPORT_SYMBOL(smp_topology);
|
|
|
|
#if CHIP_HAS_IPI()
|
|
static unsigned long __iomem *ipi_mappings[NR_CPUS];
|
|
#endif
|
|
|
|
|
|
/*
|
|
* Top-level send_IPI*() functions to send messages to other cpus.
|
|
*/
|
|
|
|
/* Set by smp_send_stop() to avoid recursive panics. */
|
|
static int stopping_cpus;
|
|
|
|
static void __send_IPI_many(HV_Recipient *recip, int nrecip, int tag)
|
|
{
|
|
int sent = 0;
|
|
while (sent < nrecip) {
|
|
int rc = hv_send_message(recip, nrecip,
|
|
(HV_VirtAddr)&tag, sizeof(tag));
|
|
if (rc < 0) {
|
|
if (!stopping_cpus) /* avoid recursive panic */
|
|
panic("hv_send_message returned %d", rc);
|
|
break;
|
|
}
|
|
WARN_ONCE(rc == 0, "hv_send_message() returned zero\n");
|
|
sent += rc;
|
|
}
|
|
}
|
|
|
|
void send_IPI_single(int cpu, int tag)
|
|
{
|
|
HV_Recipient recip = {
|
|
.y = cpu / smp_width,
|
|
.x = cpu % smp_width,
|
|
.state = HV_TO_BE_SENT
|
|
};
|
|
__send_IPI_many(&recip, 1, tag);
|
|
}
|
|
|
|
void send_IPI_many(const struct cpumask *mask, int tag)
|
|
{
|
|
HV_Recipient recip[NR_CPUS];
|
|
int cpu;
|
|
int nrecip = 0;
|
|
int my_cpu = smp_processor_id();
|
|
for_each_cpu(cpu, mask) {
|
|
HV_Recipient *r;
|
|
BUG_ON(cpu == my_cpu);
|
|
r = &recip[nrecip++];
|
|
r->y = cpu / smp_width;
|
|
r->x = cpu % smp_width;
|
|
r->state = HV_TO_BE_SENT;
|
|
}
|
|
__send_IPI_many(recip, nrecip, tag);
|
|
}
|
|
|
|
void send_IPI_allbutself(int tag)
|
|
{
|
|
struct cpumask mask;
|
|
cpumask_copy(&mask, cpu_online_mask);
|
|
cpumask_clear_cpu(smp_processor_id(), &mask);
|
|
send_IPI_many(&mask, tag);
|
|
}
|
|
|
|
/*
|
|
* Functions related to starting/stopping cpus.
|
|
*/
|
|
|
|
/* Handler to start the current cpu. */
|
|
static void smp_start_cpu_interrupt(void)
|
|
{
|
|
get_irq_regs()->pc = start_cpu_function_addr;
|
|
}
|
|
|
|
/* Handler to stop the current cpu. */
|
|
static void smp_stop_cpu_interrupt(void)
|
|
{
|
|
set_cpu_online(smp_processor_id(), 0);
|
|
arch_local_irq_disable_all();
|
|
for (;;)
|
|
asm("nap; nop");
|
|
}
|
|
|
|
/* This function calls the 'stop' function on all other CPUs in the system. */
|
|
void smp_send_stop(void)
|
|
{
|
|
stopping_cpus = 1;
|
|
send_IPI_allbutself(MSG_TAG_STOP_CPU);
|
|
}
|
|
|
|
/* On panic, just wait; we may get an smp_send_stop() later on. */
|
|
void panic_smp_self_stop(void)
|
|
{
|
|
while (1)
|
|
asm("nap; nop");
|
|
}
|
|
|
|
/*
|
|
* Dispatch code called from hv_message_intr() for HV_MSG_TILE hv messages.
|
|
*/
|
|
void evaluate_message(int tag)
|
|
{
|
|
switch (tag) {
|
|
case MSG_TAG_START_CPU: /* Start up a cpu */
|
|
smp_start_cpu_interrupt();
|
|
break;
|
|
|
|
case MSG_TAG_STOP_CPU: /* Sent to shut down slave CPU's */
|
|
smp_stop_cpu_interrupt();
|
|
break;
|
|
|
|
case MSG_TAG_CALL_FUNCTION_MANY: /* Call function on cpumask */
|
|
generic_smp_call_function_interrupt();
|
|
break;
|
|
|
|
case MSG_TAG_CALL_FUNCTION_SINGLE: /* Call function on one other CPU */
|
|
generic_smp_call_function_single_interrupt();
|
|
break;
|
|
|
|
default:
|
|
panic("Unknown IPI message tag %d", tag);
|
|
break;
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* flush_icache_range() code uses smp_call_function().
|
|
*/
|
|
|
|
struct ipi_flush {
|
|
unsigned long start;
|
|
unsigned long end;
|
|
};
|
|
|
|
static void ipi_flush_icache_range(void *info)
|
|
{
|
|
struct ipi_flush *flush = (struct ipi_flush *) info;
|
|
__flush_icache_range(flush->start, flush->end);
|
|
}
|
|
|
|
void flush_icache_range(unsigned long start, unsigned long end)
|
|
{
|
|
struct ipi_flush flush = { start, end };
|
|
preempt_disable();
|
|
on_each_cpu(ipi_flush_icache_range, &flush, 1);
|
|
preempt_enable();
|
|
}
|
|
|
|
|
|
/* Called when smp_send_reschedule() triggers IRQ_RESCHEDULE. */
|
|
static irqreturn_t handle_reschedule_ipi(int irq, void *token)
|
|
{
|
|
__get_cpu_var(irq_stat).irq_resched_count++;
|
|
scheduler_ipi();
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
static struct irqaction resched_action = {
|
|
.handler = handle_reschedule_ipi,
|
|
.name = "resched",
|
|
.dev_id = handle_reschedule_ipi /* unique token */,
|
|
};
|
|
|
|
void __init ipi_init(void)
|
|
{
|
|
#if CHIP_HAS_IPI()
|
|
int cpu;
|
|
/* Map IPI trigger MMIO addresses. */
|
|
for_each_possible_cpu(cpu) {
|
|
HV_Coord tile;
|
|
HV_PTE pte;
|
|
unsigned long offset;
|
|
|
|
tile.x = cpu_x(cpu);
|
|
tile.y = cpu_y(cpu);
|
|
if (hv_get_ipi_pte(tile, KERNEL_PL, &pte) != 0)
|
|
panic("Failed to initialize IPI for cpu %d\n", cpu);
|
|
|
|
offset = PFN_PHYS(pte_pfn(pte));
|
|
ipi_mappings[cpu] = ioremap_prot(offset, PAGE_SIZE, pte);
|
|
}
|
|
#endif
|
|
|
|
/* Bind handle_reschedule_ipi() to IRQ_RESCHEDULE. */
|
|
tile_irq_activate(IRQ_RESCHEDULE, TILE_IRQ_PERCPU);
|
|
BUG_ON(setup_irq(IRQ_RESCHEDULE, &resched_action));
|
|
}
|
|
|
|
#if CHIP_HAS_IPI()
|
|
|
|
void smp_send_reschedule(int cpu)
|
|
{
|
|
WARN_ON(cpu_is_offline(cpu));
|
|
|
|
/*
|
|
* We just want to do an MMIO store. The traditional writeq()
|
|
* functions aren't really correct here, since they're always
|
|
* directed at the PCI shim. For now, just do a raw store,
|
|
* casting away the __iomem attribute.
|
|
*/
|
|
((unsigned long __force *)ipi_mappings[cpu])[IRQ_RESCHEDULE] = 0;
|
|
}
|
|
|
|
#else
|
|
|
|
void smp_send_reschedule(int cpu)
|
|
{
|
|
HV_Coord coord;
|
|
|
|
WARN_ON(cpu_is_offline(cpu));
|
|
|
|
coord.y = cpu_y(cpu);
|
|
coord.x = cpu_x(cpu);
|
|
hv_trigger_ipi(coord, IRQ_RESCHEDULE);
|
|
}
|
|
|
|
#endif /* CHIP_HAS_IPI() */
|