linux-stable/arch/powerpc/sysdev/xics/icp-native.c
Thomas Gleixner 2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
Based on 1 normalized pattern(s):

  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

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00

350 lines
7.7 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright 2011 IBM Corporation.
*/
#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/module.h>
#include <asm/prom.h>
#include <asm/io.h>
#include <asm/smp.h>
#include <asm/irq.h>
#include <asm/errno.h>
#include <asm/xics.h>
#include <asm/kvm_ppc.h>
#include <asm/dbell.h>
struct icp_ipl {
union {
u32 word;
u8 bytes[4];
} xirr_poll;
union {
u32 word;
u8 bytes[4];
} xirr;
u32 dummy;
union {
u32 word;
u8 bytes[4];
} qirr;
u32 link_a;
u32 link_b;
u32 link_c;
};
static struct icp_ipl __iomem *icp_native_regs[NR_CPUS];
static inline unsigned int icp_native_get_xirr(void)
{
int cpu = smp_processor_id();
unsigned int xirr;
/* Handled an interrupt latched by KVM */
xirr = kvmppc_get_xics_latch();
if (xirr)
return xirr;
return in_be32(&icp_native_regs[cpu]->xirr.word);
}
static inline void icp_native_set_xirr(unsigned int value)
{
int cpu = smp_processor_id();
out_be32(&icp_native_regs[cpu]->xirr.word, value);
}
static inline void icp_native_set_cppr(u8 value)
{
int cpu = smp_processor_id();
out_8(&icp_native_regs[cpu]->xirr.bytes[0], value);
}
static inline void icp_native_set_qirr(int n_cpu, u8 value)
{
out_8(&icp_native_regs[n_cpu]->qirr.bytes[0], value);
}
static void icp_native_set_cpu_priority(unsigned char cppr)
{
xics_set_base_cppr(cppr);
icp_native_set_cppr(cppr);
iosync();
}
void icp_native_eoi(struct irq_data *d)
{
unsigned int hw_irq = (unsigned int)irqd_to_hwirq(d);
iosync();
icp_native_set_xirr((xics_pop_cppr() << 24) | hw_irq);
}
static void icp_native_teardown_cpu(void)
{
int cpu = smp_processor_id();
/* Clear any pending IPI */
icp_native_set_qirr(cpu, 0xff);
}
static void icp_native_flush_ipi(void)
{
/* We take the ipi irq but and never return so we
* need to EOI the IPI, but want to leave our priority 0
*
* should we check all the other interrupts too?
* should we be flagging idle loop instead?
* or creating some task to be scheduled?
*/
icp_native_set_xirr((0x00 << 24) | XICS_IPI);
}
static unsigned int icp_native_get_irq(void)
{
unsigned int xirr = icp_native_get_xirr();
unsigned int vec = xirr & 0x00ffffff;
unsigned int irq;
if (vec == XICS_IRQ_SPURIOUS)
return 0;
irq = irq_find_mapping(xics_host, vec);
if (likely(irq)) {
xics_push_cppr(vec);
return irq;
}
/* We don't have a linux mapping, so have rtas mask it. */
xics_mask_unknown_vec(vec);
/* We might learn about it later, so EOI it */
icp_native_set_xirr(xirr);
return 0;
}
#ifdef CONFIG_SMP
static void icp_native_cause_ipi(int cpu)
{
kvmppc_set_host_ipi(cpu, 1);
icp_native_set_qirr(cpu, IPI_PRIORITY);
}
#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
void icp_native_cause_ipi_rm(int cpu)
{
/*
* Currently not used to send IPIs to another CPU
* on the same core. Only caller is KVM real mode.
* Need the physical address of the XICS to be
* previously saved in kvm_hstate in the paca.
*/
void __iomem *xics_phys;
/*
* Just like the cause_ipi functions, it is required to
* include a full barrier before causing the IPI.
*/
xics_phys = paca_ptrs[cpu]->kvm_hstate.xics_phys;
mb();
__raw_rm_writeb(IPI_PRIORITY, xics_phys + XICS_MFRR);
}
#endif
/*
* Called when an interrupt is received on an off-line CPU to
* clear the interrupt, so that the CPU can go back to nap mode.
*/
void icp_native_flush_interrupt(void)
{
unsigned int xirr = icp_native_get_xirr();
unsigned int vec = xirr & 0x00ffffff;
if (vec == XICS_IRQ_SPURIOUS)
return;
if (vec == XICS_IPI) {
/* Clear pending IPI */
int cpu = smp_processor_id();
kvmppc_set_host_ipi(cpu, 0);
icp_native_set_qirr(cpu, 0xff);
} else {
pr_err("XICS: hw interrupt 0x%x to offline cpu, disabling\n",
vec);
xics_mask_unknown_vec(vec);
}
/* EOI the interrupt */
icp_native_set_xirr(xirr);
}
void xics_wake_cpu(int cpu)
{
icp_native_set_qirr(cpu, IPI_PRIORITY);
}
EXPORT_SYMBOL_GPL(xics_wake_cpu);
static irqreturn_t icp_native_ipi_action(int irq, void *dev_id)
{
int cpu = smp_processor_id();
kvmppc_set_host_ipi(cpu, 0);
icp_native_set_qirr(cpu, 0xff);
return smp_ipi_demux();
}
#endif /* CONFIG_SMP */
static int __init icp_native_map_one_cpu(int hw_id, unsigned long addr,
unsigned long size)
{
char *rname;
int i, cpu = -1;
/* This may look gross but it's good enough for now, we don't quite
* have a hard -> linux processor id matching.
*/
for_each_possible_cpu(i) {
if (!cpu_present(i))
continue;
if (hw_id == get_hard_smp_processor_id(i)) {
cpu = i;
break;
}
}
/* Fail, skip that CPU. Don't print, it's normal, some XICS come up
* with way more entries in there than you have CPUs
*/
if (cpu == -1)
return 0;
rname = kasprintf(GFP_KERNEL, "CPU %d [0x%x] Interrupt Presentation",
cpu, hw_id);
if (!request_mem_region(addr, size, rname)) {
pr_warn("icp_native: Could not reserve ICP MMIO for CPU %d, interrupt server #0x%x\n",
cpu, hw_id);
return -EBUSY;
}
icp_native_regs[cpu] = ioremap(addr, size);
kvmppc_set_xics_phys(cpu, addr);
if (!icp_native_regs[cpu]) {
pr_warn("icp_native: Failed ioremap for CPU %d, interrupt server #0x%x, addr %#lx\n",
cpu, hw_id, addr);
release_mem_region(addr, size);
return -ENOMEM;
}
return 0;
}
static int __init icp_native_init_one_node(struct device_node *np,
unsigned int *indx)
{
unsigned int ilen;
const __be32 *ireg;
int i;
int reg_tuple_size;
int num_servers = 0;
/* This code does the theorically broken assumption that the interrupt
* server numbers are the same as the hard CPU numbers.
* This happens to be the case so far but we are playing with fire...
* should be fixed one of these days. -BenH.
*/
ireg = of_get_property(np, "ibm,interrupt-server-ranges", &ilen);
/* Do that ever happen ? we'll know soon enough... but even good'old
* f80 does have that property ..
*/
WARN_ON((ireg == NULL) || (ilen != 2*sizeof(u32)));
if (ireg) {
*indx = of_read_number(ireg, 1);
if (ilen >= 2*sizeof(u32))
num_servers = of_read_number(ireg + 1, 1);
}
ireg = of_get_property(np, "reg", &ilen);
if (!ireg) {
pr_err("icp_native: Can't find interrupt reg property");
return -1;
}
reg_tuple_size = (of_n_addr_cells(np) + of_n_size_cells(np)) * 4;
if (((ilen % reg_tuple_size) != 0)
|| (num_servers && (num_servers != (ilen / reg_tuple_size)))) {
pr_err("icp_native: ICP reg len (%d) != num servers (%d)",
ilen / reg_tuple_size, num_servers);
return -1;
}
for (i = 0; i < (ilen / reg_tuple_size); i++) {
struct resource r;
int err;
err = of_address_to_resource(np, i, &r);
if (err) {
pr_err("icp_native: Could not translate ICP MMIO"
" for interrupt server 0x%x (%d)\n", *indx, err);
return -1;
}
if (icp_native_map_one_cpu(*indx, r.start, resource_size(&r)))
return -1;
(*indx)++;
}
return 0;
}
static const struct icp_ops icp_native_ops = {
.get_irq = icp_native_get_irq,
.eoi = icp_native_eoi,
.set_priority = icp_native_set_cpu_priority,
.teardown_cpu = icp_native_teardown_cpu,
.flush_ipi = icp_native_flush_ipi,
#ifdef CONFIG_SMP
.ipi_action = icp_native_ipi_action,
.cause_ipi = icp_native_cause_ipi,
#endif
};
int __init icp_native_init(void)
{
struct device_node *np;
u32 indx = 0;
int found = 0;
for_each_compatible_node(np, NULL, "ibm,ppc-xicp")
if (icp_native_init_one_node(np, &indx) == 0)
found = 1;
if (!found) {
for_each_node_by_type(np,
"PowerPC-External-Interrupt-Presentation") {
if (icp_native_init_one_node(np, &indx) == 0)
found = 1;
}
}
if (found == 0)
return -ENODEV;
icp_ops = &icp_native_ops;
return 0;
}