* [PATCH 0 of 9] (v2) arm: SMP boot
@ 2012-03-09 13:43 Tim Deegan
2012-03-09 13:43 ` [PATCH 1 of 9] arm: implement udelay() Tim Deegan
` (8 more replies)
0 siblings, 9 replies; 11+ messages in thread
From: Tim Deegan @ 2012-03-09 13:43 UTC (permalink / raw)
To: xen-devel; +Cc: David Vrabel, Stefano Stabellini, Ian Campbell
This patch series implements SMP boot for arch/arm, as far as getting
all CPUs up and running the idle loop.
Changes from v1:
- moved barriers out of loop in udelay()
- dropped broken GIC change in favour of explanatory comment
- made the increment of ready_cpus atomic (I couldn't move the
increment to before signalling the next CPU because the PT
switch has to happen between them)
- Made secondary CPUs come up directly on the idle vcpus' stacks,
avoiding the whole business of allocating and tracking boot stacks.
- Added a new patch to do late-boot MMU fixups on secondary CPUs.
Cheers,
Tim.
^ permalink raw reply [flat|nested] 11+ messages in thread
* [PATCH 1 of 9] arm: implement udelay()
2012-03-09 13:43 [PATCH 0 of 9] (v2) arm: SMP boot Tim Deegan
@ 2012-03-09 13:43 ` Tim Deegan
2012-03-09 13:43 ` [PATCH 2 of 9] arm: Add a comment explaining the GICD writes in the GICC init function Tim Deegan
` (7 subsequent siblings)
8 siblings, 0 replies; 11+ messages in thread
From: Tim Deegan @ 2012-03-09 13:43 UTC (permalink / raw)
To: xen-devel; +Cc: David Vrabel, Stefano Stabellini, Ian Campbell
# HG changeset patch
# User Tim Deegan <tim@xen.org>
# Date 1331300346 0
# Node ID 7a00e582027ed2793f4ee393f94ddf790b61c39f
# Parent 10c5ba0b5af2dd209d4f7d27649dea5827652d9c
arm: implement udelay()
Signed-off-by: Tim Deegan <tim@xen.org>
diff -r 10c5ba0b5af2 -r 7a00e582027e xen/arch/arm/dummy.S
--- a/xen/arch/arm/dummy.S Fri Mar 09 09:58:41 2012 +0000
+++ b/xen/arch/arm/dummy.S Fri Mar 09 13:39:06 2012 +0000
@@ -62,5 +62,4 @@ DUMMY(gmfn_to_mfn);
DUMMY(hypercall_create_continuation);
DUMMY(send_timer_event);
DUMMY(share_xen_page_with_privileged_guests);
-DUMMY(__udelay);
DUMMY(wallclock_time);
diff -r 10c5ba0b5af2 -r 7a00e582027e xen/arch/arm/time.c
--- a/xen/arch/arm/time.c Fri Mar 09 09:58:41 2012 +0000
+++ b/xen/arch/arm/time.c Fri Mar 09 13:39:06 2012 +0000
@@ -171,6 +171,16 @@ void __cpuinit init_timer_interrupt(void
request_irq(30, timer_interrupt, 0, "phytimer", NULL);
}
+/* Wait a set number of microseconds */
+void udelay(unsigned long usecs)
+{
+ s_time_t deadline = get_s_time() + 1000 * (s_time_t) usecs;
+ while ( get_s_time() - deadline < 0 )
+ ;
+ dsb();
+ isb();
+}
+
/*
* Local variables:
* mode: C
diff -r 10c5ba0b5af2 -r 7a00e582027e xen/include/asm-arm/delay.h
--- a/xen/include/asm-arm/delay.h Fri Mar 09 09:58:41 2012 +0000
+++ b/xen/include/asm-arm/delay.h Fri Mar 09 13:39:06 2012 +0000
@@ -1,8 +1,7 @@
#ifndef _ARM_DELAY_H
#define _ARM_DELAY_H
-extern void __udelay(unsigned long usecs);
-#define udelay(n) __udelay(n)
+extern void udelay(unsigned long usecs);
#endif /* defined(_ARM_DELAY_H) */
/*
^ permalink raw reply [flat|nested] 11+ messages in thread
* [PATCH 2 of 9] arm: Add a comment explaining the GICD writes in the GICC init function
2012-03-09 13:43 [PATCH 0 of 9] (v2) arm: SMP boot Tim Deegan
2012-03-09 13:43 ` [PATCH 1 of 9] arm: implement udelay() Tim Deegan
@ 2012-03-09 13:43 ` Tim Deegan
2012-03-09 13:43 ` [PATCH 3 of 9] arm: More SMP bringup Tim Deegan
` (6 subsequent siblings)
8 siblings, 0 replies; 11+ messages in thread
From: Tim Deegan @ 2012-03-09 13:43 UTC (permalink / raw)
To: xen-devel; +Cc: David Vrabel, Stefano Stabellini, Ian Campbell
# HG changeset patch
# User Tim Deegan <tim@xen.org>
# Date 1331300346 0
# Node ID 51da35a2e502779efb78402013da38a1960a6129
# Parent 7a00e582027ed2793f4ee393f94ddf790b61c39f
arm: Add a comment explaining the GICD writes in the GICC init function.
Signed-off-by: Tim Deegan <tim@xen.org>
diff -r 7a00e582027e -r 51da35a2e502 xen/arch/arm/gic.c
--- a/xen/arch/arm/gic.c Fri Mar 09 13:39:06 2012 +0000
+++ b/xen/arch/arm/gic.c Fri Mar 09 13:39:06 2012 +0000
@@ -224,7 +224,9 @@ static void __cpuinit gic_cpu_init(void)
{
int i;
- /* Disable all PPI and enable all SGI */
+ /* The first 32 interrupts (PPI and SGI) are banked per-cpu, so
+ * even though they are controlled with GICD registers, they must
+ * be set up here with the other per-cpu state. */
GICD[GICD_ICENABLER] = 0xffff0000; /* Disable all PPI */
GICD[GICD_ISENABLER] = 0x0000ffff; /* Enable all SGI */
/* Set PPI and SGI priorities */
^ permalink raw reply [flat|nested] 11+ messages in thread
* [PATCH 3 of 9] arm: More SMP bringup
2012-03-09 13:43 [PATCH 0 of 9] (v2) arm: SMP boot Tim Deegan
2012-03-09 13:43 ` [PATCH 1 of 9] arm: implement udelay() Tim Deegan
2012-03-09 13:43 ` [PATCH 2 of 9] arm: Add a comment explaining the GICD writes in the GICC init function Tim Deegan
@ 2012-03-09 13:43 ` Tim Deegan
2012-03-09 13:43 ` [PATCH 4 of 9] arm: per-cpu areas Tim Deegan
` (5 subsequent siblings)
8 siblings, 0 replies; 11+ messages in thread
From: Tim Deegan @ 2012-03-09 13:43 UTC (permalink / raw)
To: xen-devel; +Cc: David Vrabel, Stefano Stabellini, Ian Campbell
# HG changeset patch
# User Tim Deegan <tim@xen.org>
# Date 1331300346 0
# Node ID ef66ce0f4fb3bfe72acd691e4db33f0c1ea9137d
# Parent 51da35a2e502779efb78402013da38a1960a6129
arm: More SMP bringup
Bring non-boot CPUs up as far as running on the relocated pagetables,
one at a time, before the non-relocated copy of Xen gets reused for
general memory pools.
Don't yet bring them up into C; that will happen later when stacks are
allocated.
Signed-off-by: Tim Deegan <tim@xen.org>
diff -r 51da35a2e502 -r ef66ce0f4fb3 xen/arch/arm/gic.c
--- a/xen/arch/arm/gic.c Fri Mar 09 13:39:06 2012 +0000
+++ b/xen/arch/arm/gic.c Fri Mar 09 13:39:06 2012 +0000
@@ -252,7 +252,7 @@ static void __cpuinit gic_hyp_init(void)
}
/* Set up the GIC */
-void gic_init(void)
+int __init gic_init(void)
{
/* XXX FIXME get this from devicetree */
gic.dbase = GIC_BASE_ADDRESS + GIC_DR_OFFSET;
@@ -274,6 +274,8 @@ void gic_init(void)
gic_hyp_init();
spin_unlock(&gic.lock);
+
+ return gic.cpus;
}
void gic_route_irqs(void)
diff -r 51da35a2e502 -r ef66ce0f4fb3 xen/arch/arm/gic.h
--- a/xen/arch/arm/gic.h Fri Mar 09 13:39:06 2012 +0000
+++ b/xen/arch/arm/gic.h Fri Mar 09 13:39:06 2012 +0000
@@ -138,8 +138,8 @@ extern int gic_route_irq_to_guest(struct
/* Accept an interrupt from the GIC and dispatch its handler */
extern void gic_interrupt(struct cpu_user_regs *regs, int is_fiq);
-/* Bring up the interrupt controller */
-extern void gic_init(void);
+/* Bring up the interrupt controller, and report # cpus attached */
+extern int gic_init(void);
/* setup the gic virtual interface for a guest */
extern void gicv_setup(struct domain *d);
#endif
diff -r 51da35a2e502 -r ef66ce0f4fb3 xen/arch/arm/head.S
--- a/xen/arch/arm/head.S Fri Mar 09 13:39:06 2012 +0000
+++ b/xen/arch/arm/head.S Fri Mar 09 13:39:06 2012 +0000
@@ -62,22 +62,36 @@ start:
#endif
/* Are we the boot CPU? */
+ mov r12, #0 /* r12 := CPU ID */
mrc CP32(r0, MPIDR)
tst r0, #(1<<31) /* Multiprocessor extension supported? */
beq boot_cpu
tst r0, #(1<<30) /* Uniprocessor system? */
bne boot_cpu
- bics r0, r0, #(0xff << 24) /* Ignore flags */
- beq boot_cpu /* If all other fields are 0, we win */
+ bics r12, r0, #(0xff << 24) /* Mask out flags to get CPU ID */
+ beq boot_cpu /* If we're CPU 0, boot now */
-1: wfi
- b 1b
-
+ /* Non-boot CPUs wait here to be woken up one at a time.
+ * This is basically an open-coded spin-lock to serialize. */
+ ldr r0, =boot_gate /* VA of gate */
+ add r0, r0, r10 /* PA of gate */
+ mov r1, #1 /* (1 == locked) */
+1: wfe
+ ldrex r2, [r0] /* Linked read of current value */
+ teq r2, #0 /* (0 == unlocked) */
+ strexeq r2, r1, [r0] /* Matching update -> locked */
+ teq r2, #0 /* (0 == succeeded) */
+ bne 1b
+
boot_cpu:
#ifdef EARLY_UART_ADDRESS
- /* Say hello */
ldr r11, =EARLY_UART_ADDRESS /* r11 := UART base address */
- bl init_uart
+ teq r12, #0 /* CPU 0 sets up the UART too */
+ bleq init_uart
+ PRINT("- CPU ")
+ mov r0, r12
+ bl putn
+ PRINT(" booting -\r\n")
#endif
/* Check that this CPU has Hyp mode */
@@ -85,7 +99,6 @@ boot_cpu:
and r0, r0, #0xf000 /* Bits 12-15 define virt extensions */
teq r0, #0x1000 /* Must == 0x1 or may be incompatible */
beq 1f
- bl putn
PRINT("- CPU doesn't support the virtualization extensions -\r\n")
b fail
1:
@@ -185,6 +198,10 @@ hyp:
mov r5, #0 /* r4:r5 is paddr (xen_pagetable) */
mcrr CP64(r4, r5, HTTBR)
+ /* Non-boot CPUs don't need to rebuild the pagetable */
+ teq r12, #0
+ bne pt_ready
+
/* Build the baseline idle pagetable's first-level entries */
ldr r1, =xen_second
add r1, r1, r10 /* r1 := paddr (xen_second) */
@@ -226,6 +243,7 @@ hyp:
add r4, r4, #8
strd r2, r3, [r1, r4] /* Map it in the early boot slot */
+pt_ready:
PRINT("- Turning on paging -\r\n")
ldr r1, =paging /* Explicit vaddr, not RIP-relative */
@@ -238,7 +256,7 @@ hyp:
paging:
#ifdef EARLY_UART_ADDRESS
- /* Recover the UART address in the new address space */
+ /* Recover the UART address in the new address space. */
lsl r11, #11
lsr r11, #11 /* UART base's offset from 2MB base */
adr r0, start
@@ -246,14 +264,59 @@ paging:
add r11, r11, r0 /* r11 := vaddr (UART base address) */
#endif
- PRINT("- Entering C -\r\n")
+ PRINT("- Ready -\r\n")
+ /* The boot CPU should go straight into C now */
+ teq r12, #0
+ beq launch
+
+ /* Signal the next non-boot CPU to come and join us here */
+ ldr r0, =boot_gate /* VA of gate */
+ add r0, r0, r10 /* PA of gate */
+ mov r1, #0 /* (0 == unlocked) */
+ str r1, [r0]
+ dsb
+ isb
+ sev
+
+ /* Move on to the relocated pagetables */
+ mov r0, #0
+ ldr r4, =boot_httbr /* VA of HTTBR value stashed by CPU 0 */
+ add r4, r4, r10 /* PA of it */
+ ldrd r4, r5, [r4] /* Actual value */
+ mcrr CP64(r4, r5, HTTBR)
+ mcr CP32(r0, TLBIALLH) /* Flush hypervisor TLB */
+ mcr CP32(r0, BPIALL) /* Flush branch predictor */
+ dsb /* Ensure completion of TLB+BP flush */
+ isb
+ /* Now, the UART is in its proper fixmap address */
+ ldrne r11, =FIXMAP_ADDR(FIXMAP_CONSOLE)
+
+ /* Non-boot CPUs report that they've got this far */
+ ldr r0, =ready_cpus
+1: ldrex r1, [r0] /* { read # of ready CPUs } */
+ add r1, r1, #1 /* Atomically { ++ } */
+ strex r2, r1, [r0] /* { writeback } */
+ teq r2, #0
+ bne 1b
+ dsb
+
+ /* Here, the non-boot CPUs must wait again -- they're now running on
+ * the boot CPU's pagetables so it's safe for the boot CPU to
+ * overwrite the non-relocated copy of Xen. Once it's done that,
+ * and brought up the memory allocator, non-boot CPUs can get their
+ * own stacks and enter C. */
+1: wfe
+ b 1b
+
+launch:
ldr sp, =init_stack /* Supply a stack */
add sp, #STACK_SIZE /* (which grows down from the top). */
sub sp, #CPUINFO_sizeof /* Make room for CPU save record */
mov r0, r10 /* Marshal args: - phys_offset */
mov r1, r7 /* - machine type */
mov r2, r8 /* - ATAG address */
+ mov r3, r12 /* - CPU ID */
b start_xen /* and disappear into the land of C */
/* Fail-stop
@@ -288,7 +351,7 @@ puts:
tst r2, #0x8 /* Check BUSY bit */
bne puts /* Wait for the UART to be ready */
ldrb r2, [r0], #1 /* Load next char */
- teq r2, #0 /* Exit on nul*/
+ teq r2, #0 /* Exit on nul */
moveq pc, lr
str r2, [r11] /* -> UARTDR (Data Register) */
b puts
@@ -308,10 +371,8 @@ 1: ldr r2, [r11, #0x18] /* <- UA
lsl r0, #4 /* Roll it through one nybble at a time */
subs r3, r3, #1
bne 1b
- adr r0, crlf /* Finish with a newline */
- b puts
+ mov pc, lr
-crlf: .asciz "\r\n"
hex: .ascii "0123456789abcdef"
.align 2
diff -r 51da35a2e502 -r ef66ce0f4fb3 xen/arch/arm/mm.c
--- a/xen/arch/arm/mm.c Fri Mar 09 13:39:06 2012 +0000
+++ b/xen/arch/arm/mm.c Fri Mar 09 13:39:06 2012 +0000
@@ -36,6 +36,9 @@ lpae_t xen_second[LPAE_ENTRIES*4] __attr
static lpae_t xen_fixmap[LPAE_ENTRIES] __attribute__((__aligned__(4096)));
static lpae_t xen_xenmap[LPAE_ENTRIES] __attribute__((__aligned__(4096)));
+/* Non-boot CPUs use this to find the correct pagetables. */
+uint64_t boot_httbr;
+
/* Limits of the Xen heap */
unsigned long xenheap_mfn_start, xenheap_mfn_end;
unsigned long xenheap_virt_end;
@@ -156,14 +159,6 @@ void __init setup_pagetables(unsigned lo
lpae_t pte, *p;
int i;
- if ( boot_phys_offset != 0 )
- {
- /* Remove the old identity mapping of the boot paddr */
- pte.bits = 0;
- dest_va = (unsigned long)_start + boot_phys_offset;
- write_pte(xen_second + second_linear_offset(dest_va), pte);
- }
-
xen_paddr = device_tree_get_xen_paddr();
/* Map the destination in the boot misc area. */
@@ -186,11 +181,18 @@ void __init setup_pagetables(unsigned lo
for ( i = 0; i < 4; i++)
p[i].pt.base += (phys_offset - boot_phys_offset) >> PAGE_SHIFT;
p = (void *) xen_second + dest_va - (unsigned long) _start;
+ if ( boot_phys_offset != 0 )
+ {
+ /* Remove the old identity mapping of the boot paddr */
+ unsigned long va = (unsigned long)_start + boot_phys_offset;
+ p[second_linear_offset(va)].bits = 0;
+ }
for ( i = 0; i < 4 * LPAE_ENTRIES; i++)
if ( p[i].pt.valid )
p[i].pt.base += (phys_offset - boot_phys_offset) >> PAGE_SHIFT;
/* Change pagetables to the copy in the relocated Xen */
+ boot_httbr = (unsigned long) xen_pgtable + phys_offset;
asm volatile (
STORE_CP64(0, HTTBR) /* Change translation base */
"dsb;" /* Ensure visibility of HTTBR update */
@@ -198,7 +200,7 @@ void __init setup_pagetables(unsigned lo
STORE_CP32(0, BPIALL) /* Flush branch predictor */
"dsb;" /* Ensure completion of TLB+BP flush */
"isb;"
- : : "r" ((unsigned long) xen_pgtable + phys_offset) : "memory");
+ : : "r" (boot_httbr) : "memory");
/* Undo the temporary map */
pte.bits = 0;
diff -r 51da35a2e502 -r ef66ce0f4fb3 xen/arch/arm/setup.c
--- a/xen/arch/arm/setup.c Fri Mar 09 13:39:06 2012 +0000
+++ b/xen/arch/arm/setup.c Fri Mar 09 13:39:06 2012 +0000
@@ -44,7 +44,12 @@ static unsigned int __initdata max_cpus
/* Xen stack for bringing up the first CPU. */
unsigned char __initdata init_stack[STACK_SIZE] __attribute__((__aligned__(STACK_SIZE)));
-extern char __init_begin[], __init_end[], __bss_start[];
+extern const char __init_begin[], __init_end[], __bss_start[];
+
+/* Spinlock for serializing CPU bringup */
+unsigned long __initdata boot_gate = 1;
+/* Number of non-boot CPUs ready to enter C */
+unsigned long __initdata ready_cpus = 0;
static __attribute_used__ void init_done(void)
{
@@ -151,14 +156,17 @@ static void __init setup_mm(unsigned lon
end_boot_allocator();
}
+/* C entry point for boot CPU */
void __init start_xen(unsigned long boot_phys_offset,
unsigned long arm_type,
- unsigned long atag_paddr)
-
+ unsigned long atag_paddr,
+ unsigned long cpuid)
{
void *fdt;
size_t fdt_size;
- int i;
+ int cpus, i;
+ paddr_t gate_pa;
+ unsigned long *gate;
fdt = (void *)BOOT_MISC_VIRT_START
+ (atag_paddr & ((1 << SECOND_SHIFT) - 1));
@@ -174,14 +182,26 @@ void __init start_xen(unsigned long boot
console_init_preirq();
#endif
+ cpus = gic_init();
+
+ printk("Waiting for %i other CPUs to be ready\n", cpus - 1);
+ /* Bring the other CPUs up to paging before the original
+ * copy of .text gets overwritten. We need to use the unrelocated
+ * copy of boot_gate as that's the one the others can see. */
+ gate_pa = ((unsigned long) &boot_gate) + boot_phys_offset;
+ gate = map_domain_page(gate_pa >> PAGE_SHIFT) + (gate_pa & ~PAGE_MASK);
+ *gate = 0;
+ unmap_domain_page(gate);
+ /* Now send an event to wake the first non-boot CPU */
+ asm volatile("dsb; isb; sev");
+ /* And wait for them all to be ready. */
+ while ( ready_cpus + 1 < cpus )
+ smp_rmb();
+
__set_current((struct vcpu *)0xfffff000); /* debug sanity */
idle_vcpu[0] = current;
set_processor_id(0); /* needed early, for smp_processor_id() */
- /* TODO: smp_prepare_boot_cpu(void) */
- cpumask_set_cpu(smp_processor_id(), &cpu_online_map);
- cpumask_set_cpu(smp_processor_id(), &cpu_present_map);
-
smp_prepare_cpus(max_cpus);
init_xen_time();
@@ -208,8 +228,6 @@ void __init start_xen(unsigned long boot
init_IRQ();
- gic_init();
-
gic_route_irqs();
init_maintenance_interrupt();
^ permalink raw reply [flat|nested] 11+ messages in thread
* [PATCH 4 of 9] arm: per-cpu areas
2012-03-09 13:43 [PATCH 0 of 9] (v2) arm: SMP boot Tim Deegan
` (2 preceding siblings ...)
2012-03-09 13:43 ` [PATCH 3 of 9] arm: More SMP bringup Tim Deegan
@ 2012-03-09 13:43 ` Tim Deegan
2012-03-09 15:57 ` Tim Deegan
2012-03-09 13:43 ` [PATCH 5 of 9] arm: start plumbing in SMP bringup in C Tim Deegan
` (4 subsequent siblings)
8 siblings, 1 reply; 11+ messages in thread
From: Tim Deegan @ 2012-03-09 13:43 UTC (permalink / raw)
To: xen-devel; +Cc: David Vrabel, Stefano Stabellini, Ian Campbell
# HG changeset patch
# User Tim Deegan <tim@xen.org>
# Date 1331300346 0
# Node ID ded775f8a1278c98d8341338b47df0700992e01b
# Parent ef66ce0f4fb3bfe72acd691e4db33f0c1ea9137d
arm: per-cpu areas
Signed-off-by: Tim Deegan <tim@xen.org>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
diff -r ef66ce0f4fb3 -r ded775f8a127 xen/arch/arm/Makefile
--- a/xen/arch/arm/Makefile Fri Mar 09 13:39:06 2012 +0000
+++ b/xen/arch/arm/Makefile Fri Mar 09 13:39:06 2012 +0000
@@ -13,6 +13,7 @@ obj-y += irq.o
obj-y += kernel.o
obj-y += mm.o
obj-y += p2m.o
+obj-y += percpu.o
obj-y += guestcopy.o
obj-y += setup.o
obj-y += time.o
diff -r ef66ce0f4fb3 -r ded775f8a127 xen/arch/arm/dummy.S
--- a/xen/arch/arm/dummy.S Fri Mar 09 13:39:06 2012 +0000
+++ b/xen/arch/arm/dummy.S Fri Mar 09 13:39:06 2012 +0000
@@ -14,7 +14,6 @@ DUMMY(per_cpu__cpu_core_mask);
DUMMY(per_cpu__cpu_sibling_mask);
DUMMY(node_online_map);
DUMMY(smp_send_state_dump);
-DUMMY(__per_cpu_offset);
/* PIRQ support */
DUMMY(alloc_pirq_struct);
diff -r ef66ce0f4fb3 -r ded775f8a127 xen/arch/arm/percpu.c
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/xen/arch/arm/percpu.c Fri Mar 09 13:39:06 2012 +0000
@@ -0,0 +1,85 @@
+#include <xen/config.h>
+#include <xen/percpu.h>
+#include <xen/cpu.h>
+#include <xen/init.h>
+#include <xen/mm.h>
+#include <xen/rcupdate.h>
+
+unsigned long __per_cpu_offset[NR_CPUS];
+#define INVALID_PERCPU_AREA (-(long)__per_cpu_start)
+#define PERCPU_ORDER (get_order_from_bytes(__per_cpu_data_end-__per_cpu_start))
+
+void __init percpu_init_areas(void)
+{
+ unsigned int cpu;
+ for ( cpu = 1; cpu < NR_CPUS; cpu++ )
+ __per_cpu_offset[cpu] = INVALID_PERCPU_AREA;
+}
+
+static int init_percpu_area(unsigned int cpu)
+{
+ char *p;
+ if ( __per_cpu_offset[cpu] != INVALID_PERCPU_AREA )
+ return -EBUSY;
+ if ( (p = alloc_xenheap_pages(PERCPU_ORDER, 0)) == NULL )
+ return -ENOMEM;
+ memset(p, 0, __per_cpu_data_end - __per_cpu_start);
+ __per_cpu_offset[cpu] = p - __per_cpu_start;
+ return 0;
+}
+
+struct free_info {
+ unsigned int cpu;
+ struct rcu_head rcu;
+};
+static DEFINE_PER_CPU(struct free_info, free_info);
+
+static void _free_percpu_area(struct rcu_head *head)
+{
+ struct free_info *info = container_of(head, struct free_info, rcu);
+ unsigned int cpu = info->cpu;
+ char *p = __per_cpu_start + __per_cpu_offset[cpu];
+ free_xenheap_pages(p, PERCPU_ORDER);
+ __per_cpu_offset[cpu] = INVALID_PERCPU_AREA;
+}
+
+static void free_percpu_area(unsigned int cpu)
+{
+ struct free_info *info = &per_cpu(free_info, cpu);
+ info->cpu = cpu;
+ call_rcu(&info->rcu, _free_percpu_area);
+}
+
+static int cpu_percpu_callback(
+ struct notifier_block *nfb, unsigned long action, void *hcpu)
+{
+ unsigned int cpu = (unsigned long)hcpu;
+ int rc = 0;
+
+ switch ( action )
+ {
+ case CPU_UP_PREPARE:
+ rc = init_percpu_area(cpu);
+ break;
+ case CPU_UP_CANCELED:
+ case CPU_DEAD:
+ free_percpu_area(cpu);
+ break;
+ default:
+ break;
+ }
+
+ return !rc ? NOTIFY_DONE : notifier_from_errno(rc);
+}
+
+static struct notifier_block cpu_percpu_nfb = {
+ .notifier_call = cpu_percpu_callback,
+ .priority = 100 /* highest priority */
+};
+
+static int __init percpu_presmp_init(void)
+{
+ register_cpu_notifier(&cpu_percpu_nfb);
+ return 0;
+}
+presmp_initcall(percpu_presmp_init);
diff -r ef66ce0f4fb3 -r ded775f8a127 xen/include/asm-arm/percpu.h
--- a/xen/include/asm-arm/percpu.h Fri Mar 09 13:39:06 2012 +0000
+++ b/xen/include/asm-arm/percpu.h Fri Mar 09 13:39:06 2012 +0000
@@ -12,8 +12,11 @@ void percpu_init_areas(void);
__attribute__((__section__(".bss.percpu" #suffix))) \
__typeof__(type) per_cpu_##name
-#define per_cpu(var, cpu) ((&per_cpu__##var)[cpu?0:0])
-#define __get_cpu_var(var) per_cpu__##var
+
+#define per_cpu(var, cpu) \
+ (*RELOC_HIDE(&per_cpu__##var, __per_cpu_offset[cpu]))
+#define __get_cpu_var(var) \
+ (*RELOC_HIDE(&per_cpu__##var, get_cpu_info()->per_cpu_offset))
#define DECLARE_PER_CPU(type, name) extern __typeof__(type) per_cpu__##name
^ permalink raw reply [flat|nested] 11+ messages in thread
* [PATCH 5 of 9] arm: start plumbing in SMP bringup in C
2012-03-09 13:43 [PATCH 0 of 9] (v2) arm: SMP boot Tim Deegan
` (3 preceding siblings ...)
2012-03-09 13:43 ` [PATCH 4 of 9] arm: per-cpu areas Tim Deegan
@ 2012-03-09 13:43 ` Tim Deegan
2012-03-09 13:43 ` [PATCH 6 of 9] arm: Boot secondary CPUs into C Tim Deegan
` (3 subsequent siblings)
8 siblings, 0 replies; 11+ messages in thread
From: Tim Deegan @ 2012-03-09 13:43 UTC (permalink / raw)
To: xen-devel; +Cc: David Vrabel, Stefano Stabellini, Ian Campbell
# HG changeset patch
# User Tim Deegan <tim@xen.org>
# Date 1331300346 0
# Node ID 469d9fc8e755b8bd0de386c8cd505229ecdf061f
# Parent ded775f8a1278c98d8341338b47df0700992e01b
arm: start plumbing in SMP bringup in C
Still a noop, but no longer just a dummy symbol.
Signed-off-by: Tim Deegan <tim@xen.org>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
diff -r ded775f8a127 -r 469d9fc8e755 xen/arch/arm/dummy.S
--- a/xen/arch/arm/dummy.S Fri Mar 09 13:39:06 2012 +0000
+++ b/xen/arch/arm/dummy.S Fri Mar 09 13:39:06 2012 +0000
@@ -7,9 +7,6 @@ x: .word 0xe7f000f0 /* Undefined instruc
x: mov pc, lr
/* SMP support */
-DUMMY(__cpu_die);
-DUMMY(__cpu_disable);
-DUMMY(__cpu_up);
DUMMY(per_cpu__cpu_core_mask);
DUMMY(per_cpu__cpu_sibling_mask);
DUMMY(node_online_map);
diff -r ded775f8a127 -r 469d9fc8e755 xen/arch/arm/setup.c
--- a/xen/arch/arm/setup.c Fri Mar 09 13:39:06 2012 +0000
+++ b/xen/arch/arm/setup.c Fri Mar 09 13:39:06 2012 +0000
@@ -38,9 +38,6 @@
#include <asm/setup.h>
#include "gic.h"
-/* maxcpus: maximum number of CPUs to activate. */
-static unsigned int __initdata max_cpus = NR_CPUS;
-
/* Xen stack for bringing up the first CPU. */
unsigned char __initdata init_stack[STACK_SIZE] __attribute__((__aligned__(STACK_SIZE)));
@@ -202,7 +199,7 @@ void __init start_xen(unsigned long boot
idle_vcpu[0] = current;
set_processor_id(0); /* needed early, for smp_processor_id() */
- smp_prepare_cpus(max_cpus);
+ smp_prepare_cpus(cpus);
init_xen_time();
@@ -249,7 +246,7 @@ void __init start_xen(unsigned long boot
for_each_present_cpu ( i )
{
- if ( (num_online_cpus() < max_cpus) && !cpu_online(i) )
+ if ( (num_online_cpus() < cpus) && !cpu_online(i) )
{
int ret = cpu_up(i);
if ( ret != 0 )
diff -r ded775f8a127 -r 469d9fc8e755 xen/arch/arm/smpboot.c
--- a/xen/arch/arm/smpboot.c Fri Mar 09 13:39:06 2012 +0000
+++ b/xen/arch/arm/smpboot.c Fri Mar 09 13:39:06 2012 +0000
@@ -19,6 +19,7 @@
#include <xen/cpumask.h>
#include <xen/smp.h>
#include <xen/init.h>
+#include <xen/errno.h>
cpumask_t cpu_online_map;
EXPORT_SYMBOL(cpu_online_map);
@@ -30,16 +31,40 @@ EXPORT_SYMBOL(cpu_possible_map);
void __init
smp_prepare_cpus (unsigned int max_cpus)
{
- set_processor_id(0); /* needed early, for smp_processor_id() */
+ int i;
+ set_processor_id(0); /* needed early, for smp_processor_id() */
- cpumask_clear(&cpu_online_map);
- cpumask_clear(&cpu_present_map);
- cpumask_clear(&cpu_possible_map);
- cpumask_set_cpu(0, &cpu_online_map);
- cpumask_set_cpu(0, &cpu_present_map);
- cpumask_set_cpu(0, &cpu_possible_map);
- return;
+ cpumask_clear(&cpu_online_map);
+ cpumask_set_cpu(0, &cpu_online_map);
+
+ cpumask_clear(&cpu_possible_map);
+ for ( i = 0; i < max_cpus; i++ )
+ cpumask_set_cpu(i, &cpu_possible_map);
+ cpumask_copy(&cpu_present_map, &cpu_possible_map);
}
+
+/* Bring up a non-boot CPU */
+int __cpu_up(unsigned int cpu)
+{
+ /* Not yet... */
+ return -ENODEV;
+}
+
+/* Shut down the current CPU */
+void __cpu_disable(void)
+{
+ /* TODO: take down timers, GIC, &c. */
+ BUG();
+}
+
+/* Wait for a remote CPU to die */
+void __cpu_die(unsigned int cpu)
+{
+ /* TODO: interlock with __cpu_disable */
+ BUG();
+}
+
+
/*
* Local variables:
* mode: C
^ permalink raw reply [flat|nested] 11+ messages in thread
* [PATCH 6 of 9] arm: Boot secondary CPUs into C
2012-03-09 13:43 [PATCH 0 of 9] (v2) arm: SMP boot Tim Deegan
` (4 preceding siblings ...)
2012-03-09 13:43 ` [PATCH 5 of 9] arm: start plumbing in SMP bringup in C Tim Deegan
@ 2012-03-09 13:43 ` Tim Deegan
2012-03-09 13:43 ` [PATCH 7 of 9] arm: SMP CPU shutdown Tim Deegan
` (2 subsequent siblings)
8 siblings, 0 replies; 11+ messages in thread
From: Tim Deegan @ 2012-03-09 13:43 UTC (permalink / raw)
To: xen-devel; +Cc: David Vrabel, Stefano Stabellini, Ian Campbell
# HG changeset patch
# User Tim Deegan <tim@xen.org>
# Date 1331300346 0
# Node ID 1b26b83318b378a6e41916e230e27030ee4539e0
# Parent 469d9fc8e755b8bd0de386c8cd505229ecdf061f
arm: Boot secondary CPUs into C
Secondary CPUs come up directly onto the stack of the appropriate idle
vcpu; the boot CPU starts on a statically allocated stack and switches
over to the idle vcpu's one once the idle domain has been built.
Signed-off-by: Tim Deegan <tim@xen.org>
diff -r 469d9fc8e755 -r 1b26b83318b3 xen/arch/arm/gic.c
--- a/xen/arch/arm/gic.c Fri Mar 09 13:39:06 2012 +0000
+++ b/xen/arch/arm/gic.c Fri Mar 09 13:39:06 2012 +0000
@@ -245,7 +245,6 @@ static void __cpuinit gic_hyp_init(void)
vtr = GICH[GICH_VTR];
nr_lrs = (vtr & GICH_VTR_NRLRGS) + 1;
- printk("GICH: %d list registers available\n", nr_lrs);
GICH[GICH_HCR] = GICH_HCR_EN;
GICH[GICH_MISR] = GICH_MISR_EOI;
@@ -278,6 +277,15 @@ int __init gic_init(void)
return gic.cpus;
}
+/* Set up the per-CPU parts of the GIC for a secondary CPU */
+void __cpuinit gic_init_secondary_cpu(void)
+{
+ spin_lock(&gic.lock);
+ gic_cpu_init();
+ gic_hyp_init();
+ spin_unlock(&gic.lock);
+}
+
void gic_route_irqs(void)
{
/* XXX should get these from DT */
diff -r 469d9fc8e755 -r 1b26b83318b3 xen/arch/arm/gic.h
--- a/xen/arch/arm/gic.h Fri Mar 09 13:39:06 2012 +0000
+++ b/xen/arch/arm/gic.h Fri Mar 09 13:39:06 2012 +0000
@@ -140,6 +140,8 @@ extern int gic_route_irq_to_guest(struct
extern void gic_interrupt(struct cpu_user_regs *regs, int is_fiq);
/* Bring up the interrupt controller, and report # cpus attached */
extern int gic_init(void);
+/* Bring up a secondary CPU's per-CPU GIC interface */
+extern void gic_init_secondary_cpu(void);
/* setup the gic virtual interface for a guest */
extern void gicv_setup(struct domain *d);
#endif
diff -r 469d9fc8e755 -r 1b26b83318b3 xen/arch/arm/head.S
--- a/xen/arch/arm/head.S Fri Mar 09 13:39:06 2012 +0000
+++ b/xen/arch/arm/head.S Fri Mar 09 13:39:06 2012 +0000
@@ -307,17 +307,23 @@ 1: ldrex r1, [r0] /*
* and brought up the memory allocator, non-boot CPUs can get their
* own stacks and enter C. */
1: wfe
- b 1b
+ dsb
+ ldr r0, =smp_up_cpu
+ ldr r1, [r0] /* Which CPU is being booted? */
+ teq r1, r12 /* Is it us? */
+ bne 1b
launch:
- ldr sp, =init_stack /* Supply a stack */
+ ldr r0, =init_stack /* Find the boot-time stack */
+ ldr sp, [r0]
add sp, #STACK_SIZE /* (which grows down from the top). */
sub sp, #CPUINFO_sizeof /* Make room for CPU save record */
mov r0, r10 /* Marshal args: - phys_offset */
mov r1, r7 /* - machine type */
mov r2, r8 /* - ATAG address */
- mov r3, r12 /* - CPU ID */
- b start_xen /* and disappear into the land of C */
+ movs r3, r12 /* - CPU ID */
+ beq start_xen /* and disappear into the land of C */
+ b start_secondary /* (to the appropriate entry point) */
/* Fail-stop
* r0: string explaining why */
diff -r 469d9fc8e755 -r 1b26b83318b3 xen/arch/arm/setup.c
--- a/xen/arch/arm/setup.c Fri Mar 09 13:39:06 2012 +0000
+++ b/xen/arch/arm/setup.c Fri Mar 09 13:39:06 2012 +0000
@@ -38,9 +38,6 @@
#include <asm/setup.h>
#include "gic.h"
-/* Xen stack for bringing up the first CPU. */
-unsigned char __initdata init_stack[STACK_SIZE] __attribute__((__aligned__(STACK_SIZE)));
-
extern const char __init_begin[], __init_end[], __bss_start[];
/* Spinlock for serializing CPU bringup */
@@ -179,6 +176,8 @@ void __init start_xen(unsigned long boot
console_init_preirq();
#endif
+ percpu_init_areas();
+
cpus = gic_init();
printk("Waiting for %i other CPUs to be ready\n", cpus - 1);
@@ -197,7 +196,6 @@ void __init start_xen(unsigned long boot
__set_current((struct vcpu *)0xfffff000); /* debug sanity */
idle_vcpu[0] = current;
- set_processor_id(0); /* needed early, for smp_processor_id() */
smp_prepare_cpus(cpus);
@@ -284,7 +282,11 @@ void __init start_xen(unsigned long boot
domain_unpause_by_systemcontroller(dom0);
- reset_stack_and_jump(init_done);
+ /* Switch on to the dynamically allocated stack for the idle vcpu
+ * since the static one we're running on is about to be freed. */
+ memcpy(idle_vcpu[0]->arch.cpu_info, get_cpu_info(),
+ sizeof(struct cpu_info));
+ switch_stack_and_jump(idle_vcpu[0]->arch.cpu_info, init_done);
}
void arch_get_xen_caps(xen_capabilities_info_t *info)
diff -r 469d9fc8e755 -r 1b26b83318b3 xen/arch/arm/smpboot.c
--- a/xen/arch/arm/smpboot.c Fri Mar 09 13:39:06 2012 +0000
+++ b/xen/arch/arm/smpboot.c Fri Mar 09 13:39:06 2012 +0000
@@ -16,10 +16,15 @@
* GNU General Public License for more details.
*/
+#include <xen/cpu.h>
#include <xen/cpumask.h>
+#include <xen/errno.h>
+#include <xen/init.h>
+#include <xen/mm.h>
+#include <xen/sched.h>
#include <xen/smp.h>
-#include <xen/init.h>
-#include <xen/errno.h>
+#include <xen/softirq.h>
+#include "gic.h"
cpumask_t cpu_online_map;
EXPORT_SYMBOL(cpu_online_map);
@@ -28,6 +33,13 @@ EXPORT_SYMBOL(cpu_online_map);
cpumask_t cpu_possible_map;
EXPORT_SYMBOL(cpu_possible_map);
+/* Xen stack for bringing up the first CPU. */
+static unsigned char __initdata cpu0_boot_stack[STACK_SIZE]
+ __attribute__((__aligned__(STACK_SIZE)));
+
+/* Pointer to the stack, used by head.S when entering C */
+unsigned char *init_stack = cpu0_boot_stack;
+
void __init
smp_prepare_cpus (unsigned int max_cpus)
{
@@ -43,11 +55,43 @@ smp_prepare_cpus (unsigned int max_cpus)
cpumask_copy(&cpu_present_map, &cpu_possible_map);
}
-/* Bring up a non-boot CPU */
-int __cpu_up(unsigned int cpu)
+/* Shared state for coordinating CPU bringup */
+unsigned long smp_up_cpu = 0;
+
+/* Boot the current CPU */
+void __cpuinit start_secondary(unsigned long boot_phys_offset,
+ unsigned long arm_type,
+ unsigned long atag_paddr,
+ unsigned long cpuid)
{
- /* Not yet... */
- return -ENODEV;
+ memset(get_cpu_info(), 0, sizeof (struct cpu_info));
+
+ /* TODO: handle boards where CPUIDs are not contiguous */
+ set_processor_id(cpuid);
+
+ /* Setup Hyp vector base */
+ WRITE_CP32((uint32_t) hyp_traps_vector, HVBAR);
+
+ dprintk(XENLOG_DEBUG, "CPU %li awake.\n", cpuid);
+
+ gic_init_secondary_cpu();
+
+ set_current(idle_vcpu[cpuid]);
+ this_cpu(curr_vcpu) = current;
+
+ /* Run local notifiers */
+ notify_cpu_starting(cpuid);
+ wmb();
+
+ /* Now report this CPU is up */
+ cpumask_set_cpu(cpuid, &cpu_online_map);
+ wmb();
+
+ local_irq_enable();
+
+ dprintk(XENLOG_DEBUG, "CPU %li booted.\n", cpuid);
+
+ startup_cpu_idle_loop();
}
/* Shut down the current CPU */
@@ -57,6 +101,26 @@ void __cpu_disable(void)
BUG();
}
+/* Bring up a remote CPU */
+int __cpu_up(unsigned int cpu)
+{
+ /* Tell the remote CPU which stack to boot on. */
+ init_stack = idle_vcpu[cpu]->arch.stack;
+
+ /* Unblock the CPU. It should be waiting in the loop in head.S
+ * for an event to arrive when smp_up_cpu matches its cpuid. */
+ smp_up_cpu = cpu;
+ asm volatile("dsb; isb; sev");
+
+ while ( !cpu_online(cpu) )
+ {
+ cpu_relax();
+ process_pending_softirqs();
+ }
+
+ return 0;
+}
+
/* Wait for a remote CPU to die */
void __cpu_die(unsigned int cpu)
{
diff -r 469d9fc8e755 -r 1b26b83318b3 xen/include/asm-arm/current.h
--- a/xen/include/asm-arm/current.h Fri Mar 09 13:39:06 2012 +0000
+++ b/xen/include/asm-arm/current.h Fri Mar 09 13:39:06 2012 +0000
@@ -47,10 +47,10 @@ static inline struct cpu_info *get_cpu_i
#define guest_cpu_user_regs() (&get_cpu_info()->guest_cpu_user_regs)
-#define reset_stack_and_jump(__fn) \
- __asm__ __volatile__ ( \
- "mov sp,%0; b "STR(__fn) \
- : : "r" (guest_cpu_user_regs()) : "memory" )
+#define switch_stack_and_jump(stack, fn) \
+ asm volatile ("mov sp,%0; b " STR(fn) : : "r" (stack) : "memory" )
+
+#define reset_stack_and_jump(fn) switch_stack_and_jump(get_cpu_info(), fn)
#endif
^ permalink raw reply [flat|nested] 11+ messages in thread
* [PATCH 7 of 9] arm: SMP CPU shutdown
2012-03-09 13:43 [PATCH 0 of 9] (v2) arm: SMP boot Tim Deegan
` (5 preceding siblings ...)
2012-03-09 13:43 ` [PATCH 6 of 9] arm: Boot secondary CPUs into C Tim Deegan
@ 2012-03-09 13:43 ` Tim Deegan
2012-03-09 13:43 ` [PATCH 8 of 9] arm: Shutdown and reboot Tim Deegan
2012-03-09 13:43 ` [PATCH 9 of 9] arm: new hook for late MMU setup on secondary CPUs Tim Deegan
8 siblings, 0 replies; 11+ messages in thread
From: Tim Deegan @ 2012-03-09 13:43 UTC (permalink / raw)
To: xen-devel; +Cc: David Vrabel, Stefano Stabellini, Ian Campbell
# HG changeset patch
# User Tim Deegan <tim@xen.org>
# Date 1331300346 0
# Node ID 80b1ce050d104d9bb2ea41634e886cdc0f175c3e
# Parent 1b26b83318b378a6e41916e230e27030ee4539e0
arm: SMP CPU shutdown
For completeness, also implelent the CPU shutdown path.
Signed-off-by: Tim Deegan <tim@xen.org>
diff -r 1b26b83318b3 -r 80b1ce050d10 xen/arch/arm/domain.c
--- a/xen/arch/arm/domain.c Fri Mar 09 13:39:06 2012 +0000
+++ b/xen/arch/arm/domain.c Fri Mar 09 13:39:06 2012 +0000
@@ -31,12 +31,10 @@ void idle_loop(void)
{
for ( ; ; )
{
- /* TODO
- if ( cpu_is_offline(smp_processor_id()) )
- play_dead();
- (*pm_idle)();
- BUG();
- */
+ if ( cpu_is_offline(smp_processor_id()) )
+ stop_cpu();
+
+ /* TODO: (*pm_idle)(); */
do_tasklet();
do_softirq();
}
diff -r 1b26b83318b3 -r 80b1ce050d10 xen/arch/arm/gic.c
--- a/xen/arch/arm/gic.c Fri Mar 09 13:39:06 2012 +0000
+++ b/xen/arch/arm/gic.c Fri Mar 09 13:39:06 2012 +0000
@@ -239,6 +239,11 @@ static void __cpuinit gic_cpu_init(void)
GICC[GICC_CTLR] = GICC_CTL_ENABLE|GICC_CTL_EOI; /* Turn on delivery */
}
+static void gic_cpu_disable(void)
+{
+ GICC[GICC_CTLR] = 0;
+}
+
static void __cpuinit gic_hyp_init(void)
{
uint32_t vtr;
@@ -250,6 +255,11 @@ static void __cpuinit gic_hyp_init(void)
GICH[GICH_MISR] = GICH_MISR_EOI;
}
+static void __cpuinit gic_hyp_disable(void)
+{
+ GICH[GICH_HCR] = 0;
+}
+
/* Set up the GIC */
int __init gic_init(void)
{
@@ -286,6 +296,15 @@ void __cpuinit gic_init_secondary_cpu(vo
spin_unlock(&gic.lock);
}
+/* Shut down the per-CPU GIC interface */
+void gic_disable_cpu(void)
+{
+ spin_lock(&gic.lock);
+ gic_cpu_disable();
+ gic_hyp_disable();
+ spin_unlock(&gic.lock);
+}
+
void gic_route_irqs(void)
{
/* XXX should get these from DT */
diff -r 1b26b83318b3 -r 80b1ce050d10 xen/arch/arm/gic.h
--- a/xen/arch/arm/gic.h Fri Mar 09 13:39:06 2012 +0000
+++ b/xen/arch/arm/gic.h Fri Mar 09 13:39:06 2012 +0000
@@ -142,6 +142,8 @@ extern void gic_interrupt(struct cpu_use
extern int gic_init(void);
/* Bring up a secondary CPU's per-CPU GIC interface */
extern void gic_init_secondary_cpu(void);
+/* Take down a CPU's per-CPU GIC interface */
+extern void gic_disable_cpu(void);
/* setup the gic virtual interface for a guest */
extern void gicv_setup(struct domain *d);
#endif
diff -r 1b26b83318b3 -r 80b1ce050d10 xen/arch/arm/smpboot.c
--- a/xen/arch/arm/smpboot.c Fri Mar 09 13:39:06 2012 +0000
+++ b/xen/arch/arm/smpboot.c Fri Mar 09 13:39:06 2012 +0000
@@ -18,6 +18,7 @@
#include <xen/cpu.h>
#include <xen/cpumask.h>
+#include <xen/delay.h>
#include <xen/errno.h>
#include <xen/init.h>
#include <xen/mm.h>
@@ -57,6 +58,7 @@ smp_prepare_cpus (unsigned int max_cpus)
/* Shared state for coordinating CPU bringup */
unsigned long smp_up_cpu = 0;
+static bool_t cpu_is_dead = 0;
/* Boot the current CPU */
void __cpuinit start_secondary(unsigned long boot_phys_offset,
@@ -97,8 +99,35 @@ void __cpuinit start_secondary(unsigned
/* Shut down the current CPU */
void __cpu_disable(void)
{
- /* TODO: take down timers, GIC, &c. */
- BUG();
+ unsigned int cpu = get_processor_id();
+
+ local_irq_disable();
+ gic_disable_cpu();
+ /* Allow any queued timer interrupts to get serviced */
+ local_irq_enable();
+ mdelay(1);
+ local_irq_disable();
+
+ /* It's now safe to remove this processor from the online map */
+ cpumask_clear_cpu(cpu, &cpu_online_map);
+
+ if ( cpu_disable_scheduler(cpu) )
+ BUG();
+ mb();
+
+ /* Return to caller; eventually the IPI mechanism will unwind and the
+ * scheduler will drop to the idle loop, which will call stop_cpu(). */
+}
+
+void stop_cpu(void)
+{
+ local_irq_disable();
+ cpu_is_dead = 1;
+ /* Make sure the write happens before we sleep forever */
+ dsb();
+ isb();
+ while ( 1 )
+ asm volatile("wfi");
}
/* Bring up a remote CPU */
@@ -124,8 +153,19 @@ int __cpu_up(unsigned int cpu)
/* Wait for a remote CPU to die */
void __cpu_die(unsigned int cpu)
{
- /* TODO: interlock with __cpu_disable */
- BUG();
+ unsigned int i = 0;
+
+ while ( !cpu_is_dead )
+ {
+ mdelay(100);
+ cpu_relax();
+ process_pending_softirqs();
+ if ( (++i % 10) == 0 )
+ printk(KERN_ERR "CPU %u still not dead...\n", cpu);
+ mb();
+ }
+ cpu_is_dead = 0;
+ mb();
}
diff -r 1b26b83318b3 -r 80b1ce050d10 xen/include/asm-arm/smp.h
--- a/xen/include/asm-arm/smp.h Fri Mar 09 13:39:06 2012 +0000
+++ b/xen/include/asm-arm/smp.h Fri Mar 09 13:39:06 2012 +0000
@@ -14,6 +14,8 @@ DECLARE_PER_CPU(cpumask_var_t, cpu_core_
#define raw_smp_processor_id() (get_processor_id())
+extern void stop_cpu(void);
+
#endif
/*
* Local variables:
^ permalink raw reply [flat|nested] 11+ messages in thread
* [PATCH 8 of 9] arm: Shutdown and reboot
2012-03-09 13:43 [PATCH 0 of 9] (v2) arm: SMP boot Tim Deegan
` (6 preceding siblings ...)
2012-03-09 13:43 ` [PATCH 7 of 9] arm: SMP CPU shutdown Tim Deegan
@ 2012-03-09 13:43 ` Tim Deegan
2012-03-09 13:43 ` [PATCH 9 of 9] arm: new hook for late MMU setup on secondary CPUs Tim Deegan
8 siblings, 0 replies; 11+ messages in thread
From: Tim Deegan @ 2012-03-09 13:43 UTC (permalink / raw)
To: xen-devel; +Cc: David Vrabel, Stefano Stabellini, Ian Campbell
# HG changeset patch
# User Tim Deegan <tim@xen.org>
# Date 1331300346 0
# Node ID 78eebd867ba25f5165283b45122d1006370ae71d
# Parent 80b1ce050d104d9bb2ea41634e886cdc0f175c3e
arm: Shutdown and reboot
Reboot runes grabbed from linux's SP810 reset function.
Doesn't seem to work on the model, though.
Signed-off-by: Tim Deegan <tim@xen.org>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
diff -r 80b1ce050d10 -r 78eebd867ba2 xen/arch/arm/shutdown.c
--- a/xen/arch/arm/shutdown.c Fri Mar 09 13:39:06 2012 +0000
+++ b/xen/arch/arm/shutdown.c Fri Mar 09 13:39:06 2012 +0000
@@ -1,18 +1,64 @@
#include <xen/config.h>
+#include <xen/console.h>
+#include <xen/cpu.h>
+#include <xen/delay.h>
#include <xen/lib.h>
+#include <xen/mm.h>
+#include <xen/smp.h>
+
+static void raw_machine_reset(void)
+{
+ /* XXX get this from device tree */
+#ifdef SP810_ADDRESS
+ /* Use the SP810 system controller to force a reset */
+ volatile uint32_t *sp810;
+ set_fixmap(FIXMAP_MISC, SP810_ADDRESS >> PAGE_SHIFT, DEV_SHARED);
+ sp810 = ((uint32_t *)
+ (FIXMAP_ADDR(FIXMAP_MISC) + (SP810_ADDRESS & ~PAGE_MASK)));
+ sp810[0] = 0x3; /* switch to slow mode */
+ dsb(); isb();
+ sp810[1] = 0x1; /* writing any value to SCSYSSTAT reg will reset system */
+ dsb(); isb();
+ clear_fixmap(FIXMAP_MISC);
+#endif
+}
+
+static void halt_this_cpu(void *arg)
+{
+ __cpu_disable();
+ stop_cpu();
+}
void machine_halt(void)
{
- /* TODO: halt */
- while(1) ;
+ watchdog_disable();
+ console_start_sync();
+ local_irq_enable();
+ smp_call_function(halt_this_cpu, NULL, 0);
+ halt_this_cpu(NULL);
}
void machine_restart(unsigned int delay_millisecs)
{
- /* TODO: restart */
- printk("Cannot restart yet\n");
- while(1);
+ int timeout = 10;
+
+ local_irq_enable();
+ smp_call_function(halt_this_cpu, NULL, 0);
+ local_irq_disable();
+
+ mdelay(delay_millisecs);
+
+ /* Wait at most another 10ms for all other CPUs to go offline. */
+ while ( (num_online_cpus() > 1) && (timeout-- > 0) )
+ mdelay(1);
+
+ while ( 1 )
+ {
+ raw_machine_reset();
+ mdelay(100);
+ }
}
+
/*
* Local variables:
* mode: C
diff -r 80b1ce050d10 -r 78eebd867ba2 xen/include/asm-arm/config.h
--- a/xen/include/asm-arm/config.h Fri Mar 09 13:39:06 2012 +0000
+++ b/xen/include/asm-arm/config.h Fri Mar 09 13:39:06 2012 +0000
@@ -119,6 +119,9 @@ extern unsigned long frametable_virt_end
#define GIC_CR_OFFSET 0x2000
#define GIC_HR_OFFSET 0x4000 /* Guess work http://lists.infradead.org/pipermail/linux-arm-kernel/2011-September/064219.html */
#define GIC_VR_OFFSET 0x6000 /* Virtual Machine CPU interface) */
+/* Board-specific: base address of system controller */
+#define SP810_ADDRESS 0x1C020000
+
#endif /* __ARM_CONFIG_H__ */
/*
^ permalink raw reply [flat|nested] 11+ messages in thread
* [PATCH 9 of 9] arm: new hook for late MMU setup on secondary CPUs
2012-03-09 13:43 [PATCH 0 of 9] (v2) arm: SMP boot Tim Deegan
` (7 preceding siblings ...)
2012-03-09 13:43 ` [PATCH 8 of 9] arm: Shutdown and reboot Tim Deegan
@ 2012-03-09 13:43 ` Tim Deegan
8 siblings, 0 replies; 11+ messages in thread
From: Tim Deegan @ 2012-03-09 13:43 UTC (permalink / raw)
To: xen-devel; +Cc: David Vrabel, Stefano Stabellini, Ian Campbell
# HG changeset patch
# User Tim Deegan <tim@xen.org>
# Date 1331300395 0
# Node ID e18aa8c6c1f472bad15310a6e38457697d71540d
# Parent 78eebd867ba25f5165283b45122d1006370ae71d
arm: new hook for late MMU setup on secondary CPUs
The boot CPU turns on W^X in setup_pagetables(). Do the same for other
CPUs after they boot. If we go to per-CPU pagetables, this is where
that will happen.
Signed-off-by: Tim Deegan <tim@xen.org>
diff -r 78eebd867ba2 -r e18aa8c6c1f4 xen/arch/arm/mm.c
--- a/xen/arch/arm/mm.c Fri Mar 09 13:39:06 2012 +0000
+++ b/xen/arch/arm/mm.c Fri Mar 09 13:39:55 2012 +0000
@@ -263,6 +263,13 @@ void __init setup_pagetables(unsigned lo
WRITE_CP32(READ_CP32(HSCTLR) | SCTLR_WXN, HSCTLR);
}
+/* MMU setup for secondary CPUS (which already have paging enabled) */
+void __cpuinit mmu_init_secondary_cpu(void)
+{
+ /* From now on, no mapping may be both writable and executable. */
+ WRITE_CP32(READ_CP32(HSCTLR) | SCTLR_WXN, HSCTLR);
+}
+
/* Create Xen's mappings of memory.
* Base and virt must be 32MB aligned and size a multiple of 32MB. */
static void __init create_mappings(unsigned long virt,
diff -r 78eebd867ba2 -r e18aa8c6c1f4 xen/arch/arm/smpboot.c
--- a/xen/arch/arm/smpboot.c Fri Mar 09 13:39:06 2012 +0000
+++ b/xen/arch/arm/smpboot.c Fri Mar 09 13:39:55 2012 +0000
@@ -76,6 +76,7 @@ void __cpuinit start_secondary(unsigned
dprintk(XENLOG_DEBUG, "CPU %li awake.\n", cpuid);
+ mmu_init_secondary_cpu();
gic_init_secondary_cpu();
set_current(idle_vcpu[cpuid]);
diff -r 78eebd867ba2 -r e18aa8c6c1f4 xen/include/asm-arm/mm.h
--- a/xen/include/asm-arm/mm.h Fri Mar 09 13:39:06 2012 +0000
+++ b/xen/include/asm-arm/mm.h Fri Mar 09 13:39:55 2012 +0000
@@ -136,6 +136,8 @@ extern unsigned long total_pages;
/* Boot-time pagetable setup */
extern void setup_pagetables(unsigned long boot_phys_offset);
+/* MMU setup for seccondary CPUS (which already have paging enabled) */
+extern void __cpuinit mmu_init_secondary_cpu(void);
/* Set up the xenheap: up to 1GB of contiguous, always-mapped memory.
* Base must be 32MB aligned and size a multiple of 32MB. */
extern void setup_xenheap_mappings(unsigned long base_mfn, unsigned long nr_mfns);
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH 4 of 9] arm: per-cpu areas
2012-03-09 13:43 ` [PATCH 4 of 9] arm: per-cpu areas Tim Deegan
@ 2012-03-09 15:57 ` Tim Deegan
0 siblings, 0 replies; 11+ messages in thread
From: Tim Deegan @ 2012-03-09 15:57 UTC (permalink / raw)
To: xen-devel; +Cc: David Vrabel, Stefano Stabellini, Ian Campbell
Hold off on this - it seems to mess up context switches (something to so
with current being a per-cpu variable and per-cpu variables being
accessed via the current vcpu's stack...)
Tim.
At 13:43 +0000 on 09 Mar (1331300613), Tim Deegan wrote:
> # HG changeset patch
> # User Tim Deegan <tim@xen.org>
> # Date 1331300346 0
> # Node ID ded775f8a1278c98d8341338b47df0700992e01b
> # Parent ef66ce0f4fb3bfe72acd691e4db33f0c1ea9137d
> arm: per-cpu areas
>
> Signed-off-by: Tim Deegan <tim@xen.org>
> Acked-by: Ian Campbell <ian.campbell@citrix.com>
>
> diff -r ef66ce0f4fb3 -r ded775f8a127 xen/arch/arm/Makefile
> --- a/xen/arch/arm/Makefile Fri Mar 09 13:39:06 2012 +0000
> +++ b/xen/arch/arm/Makefile Fri Mar 09 13:39:06 2012 +0000
> @@ -13,6 +13,7 @@ obj-y += irq.o
> obj-y += kernel.o
> obj-y += mm.o
> obj-y += p2m.o
> +obj-y += percpu.o
> obj-y += guestcopy.o
> obj-y += setup.o
> obj-y += time.o
> diff -r ef66ce0f4fb3 -r ded775f8a127 xen/arch/arm/dummy.S
> --- a/xen/arch/arm/dummy.S Fri Mar 09 13:39:06 2012 +0000
> +++ b/xen/arch/arm/dummy.S Fri Mar 09 13:39:06 2012 +0000
> @@ -14,7 +14,6 @@ DUMMY(per_cpu__cpu_core_mask);
> DUMMY(per_cpu__cpu_sibling_mask);
> DUMMY(node_online_map);
> DUMMY(smp_send_state_dump);
> -DUMMY(__per_cpu_offset);
>
> /* PIRQ support */
> DUMMY(alloc_pirq_struct);
> diff -r ef66ce0f4fb3 -r ded775f8a127 xen/arch/arm/percpu.c
> --- /dev/null Thu Jan 01 00:00:00 1970 +0000
> +++ b/xen/arch/arm/percpu.c Fri Mar 09 13:39:06 2012 +0000
> @@ -0,0 +1,85 @@
> +#include <xen/config.h>
> +#include <xen/percpu.h>
> +#include <xen/cpu.h>
> +#include <xen/init.h>
> +#include <xen/mm.h>
> +#include <xen/rcupdate.h>
> +
> +unsigned long __per_cpu_offset[NR_CPUS];
> +#define INVALID_PERCPU_AREA (-(long)__per_cpu_start)
> +#define PERCPU_ORDER (get_order_from_bytes(__per_cpu_data_end-__per_cpu_start))
> +
> +void __init percpu_init_areas(void)
> +{
> + unsigned int cpu;
> + for ( cpu = 1; cpu < NR_CPUS; cpu++ )
> + __per_cpu_offset[cpu] = INVALID_PERCPU_AREA;
> +}
> +
> +static int init_percpu_area(unsigned int cpu)
> +{
> + char *p;
> + if ( __per_cpu_offset[cpu] != INVALID_PERCPU_AREA )
> + return -EBUSY;
> + if ( (p = alloc_xenheap_pages(PERCPU_ORDER, 0)) == NULL )
> + return -ENOMEM;
> + memset(p, 0, __per_cpu_data_end - __per_cpu_start);
> + __per_cpu_offset[cpu] = p - __per_cpu_start;
> + return 0;
> +}
> +
> +struct free_info {
> + unsigned int cpu;
> + struct rcu_head rcu;
> +};
> +static DEFINE_PER_CPU(struct free_info, free_info);
> +
> +static void _free_percpu_area(struct rcu_head *head)
> +{
> + struct free_info *info = container_of(head, struct free_info, rcu);
> + unsigned int cpu = info->cpu;
> + char *p = __per_cpu_start + __per_cpu_offset[cpu];
> + free_xenheap_pages(p, PERCPU_ORDER);
> + __per_cpu_offset[cpu] = INVALID_PERCPU_AREA;
> +}
> +
> +static void free_percpu_area(unsigned int cpu)
> +{
> + struct free_info *info = &per_cpu(free_info, cpu);
> + info->cpu = cpu;
> + call_rcu(&info->rcu, _free_percpu_area);
> +}
> +
> +static int cpu_percpu_callback(
> + struct notifier_block *nfb, unsigned long action, void *hcpu)
> +{
> + unsigned int cpu = (unsigned long)hcpu;
> + int rc = 0;
> +
> + switch ( action )
> + {
> + case CPU_UP_PREPARE:
> + rc = init_percpu_area(cpu);
> + break;
> + case CPU_UP_CANCELED:
> + case CPU_DEAD:
> + free_percpu_area(cpu);
> + break;
> + default:
> + break;
> + }
> +
> + return !rc ? NOTIFY_DONE : notifier_from_errno(rc);
> +}
> +
> +static struct notifier_block cpu_percpu_nfb = {
> + .notifier_call = cpu_percpu_callback,
> + .priority = 100 /* highest priority */
> +};
> +
> +static int __init percpu_presmp_init(void)
> +{
> + register_cpu_notifier(&cpu_percpu_nfb);
> + return 0;
> +}
> +presmp_initcall(percpu_presmp_init);
> diff -r ef66ce0f4fb3 -r ded775f8a127 xen/include/asm-arm/percpu.h
> --- a/xen/include/asm-arm/percpu.h Fri Mar 09 13:39:06 2012 +0000
> +++ b/xen/include/asm-arm/percpu.h Fri Mar 09 13:39:06 2012 +0000
> @@ -12,8 +12,11 @@ void percpu_init_areas(void);
> __attribute__((__section__(".bss.percpu" #suffix))) \
> __typeof__(type) per_cpu_##name
>
> -#define per_cpu(var, cpu) ((&per_cpu__##var)[cpu?0:0])
> -#define __get_cpu_var(var) per_cpu__##var
> +
> +#define per_cpu(var, cpu) \
> + (*RELOC_HIDE(&per_cpu__##var, __per_cpu_offset[cpu]))
> +#define __get_cpu_var(var) \
> + (*RELOC_HIDE(&per_cpu__##var, get_cpu_info()->per_cpu_offset))
>
> #define DECLARE_PER_CPU(type, name) extern __typeof__(type) per_cpu__##name
>
>
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@lists.xen.org
> http://lists.xen.org/xen-devel
^ permalink raw reply [flat|nested] 11+ messages in thread
end of thread, other threads:[~2012-03-09 15:57 UTC | newest]
Thread overview: 11+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2012-03-09 13:43 [PATCH 0 of 9] (v2) arm: SMP boot Tim Deegan
2012-03-09 13:43 ` [PATCH 1 of 9] arm: implement udelay() Tim Deegan
2012-03-09 13:43 ` [PATCH 2 of 9] arm: Add a comment explaining the GICD writes in the GICC init function Tim Deegan
2012-03-09 13:43 ` [PATCH 3 of 9] arm: More SMP bringup Tim Deegan
2012-03-09 13:43 ` [PATCH 4 of 9] arm: per-cpu areas Tim Deegan
2012-03-09 15:57 ` Tim Deegan
2012-03-09 13:43 ` [PATCH 5 of 9] arm: start plumbing in SMP bringup in C Tim Deegan
2012-03-09 13:43 ` [PATCH 6 of 9] arm: Boot secondary CPUs into C Tim Deegan
2012-03-09 13:43 ` [PATCH 7 of 9] arm: SMP CPU shutdown Tim Deegan
2012-03-09 13:43 ` [PATCH 8 of 9] arm: Shutdown and reboot Tim Deegan
2012-03-09 13:43 ` [PATCH 9 of 9] arm: new hook for late MMU setup on secondary CPUs Tim Deegan
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