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-rw-r--r--arch/ia64/kernel/efi.c46
-rw-r--r--arch/ia64/kernel/setup.c6
-rw-r--r--arch/ia64/mm/tlb.c161
3 files changed, 196 insertions, 17 deletions
diff --git a/arch/ia64/kernel/efi.c b/arch/ia64/kernel/efi.c
index 728d7247a1a..d45f215bc8f 100644
--- a/arch/ia64/kernel/efi.c
+++ b/arch/ia64/kernel/efi.c
@@ -37,6 +37,7 @@
#include <asm/pgtable.h>
#include <asm/processor.h>
#include <asm/mca.h>
+#include <asm/tlbflush.h>
#define EFI_DEBUG 0
@@ -403,6 +404,41 @@ efi_get_pal_addr (void)
return NULL;
}
+
+static u8 __init palo_checksum(u8 *buffer, u32 length)
+{
+ u8 sum = 0;
+ u8 *end = buffer + length;
+
+ while (buffer < end)
+ sum = (u8) (sum + *(buffer++));
+
+ return sum;
+}
+
+/*
+ * Parse and handle PALO table which is published at:
+ * http://www.dig64.org/home/DIG64_PALO_R1_0.pdf
+ */
+static void __init handle_palo(unsigned long palo_phys)
+{
+ struct palo_table *palo = __va(palo_phys);
+ u8 checksum;
+
+ if (strncmp(palo->signature, PALO_SIG, sizeof(PALO_SIG) - 1)) {
+ printk(KERN_INFO "PALO signature incorrect.\n");
+ return;
+ }
+
+ checksum = palo_checksum((u8 *)palo, palo->length);
+ if (checksum) {
+ printk(KERN_INFO "PALO checksum incorrect.\n");
+ return;
+ }
+
+ setup_ptcg_sem(palo->max_tlb_purges, NPTCG_FROM_PALO);
+}
+
void
efi_map_pal_code (void)
{
@@ -432,6 +468,7 @@ efi_init (void)
u64 efi_desc_size;
char *cp, vendor[100] = "unknown";
int i;
+ unsigned long palo_phys;
/*
* It's too early to be able to use the standard kernel command line
@@ -496,6 +533,8 @@ efi_init (void)
efi.hcdp = EFI_INVALID_TABLE_ADDR;
efi.uga = EFI_INVALID_TABLE_ADDR;
+ palo_phys = EFI_INVALID_TABLE_ADDR;
+
for (i = 0; i < (int) efi.systab->nr_tables; i++) {
if (efi_guidcmp(config_tables[i].guid, MPS_TABLE_GUID) == 0) {
efi.mps = config_tables[i].table;
@@ -515,10 +554,17 @@ efi_init (void)
} else if (efi_guidcmp(config_tables[i].guid, HCDP_TABLE_GUID) == 0) {
efi.hcdp = config_tables[i].table;
printk(" HCDP=0x%lx", config_tables[i].table);
+ } else if (efi_guidcmp(config_tables[i].guid,
+ PROCESSOR_ABSTRACTION_LAYER_OVERWRITE_GUID) == 0) {
+ palo_phys = config_tables[i].table;
+ printk(" PALO=0x%lx", config_tables[i].table);
}
}
printk("\n");
+ if (palo_phys != EFI_INVALID_TABLE_ADDR)
+ handle_palo(palo_phys);
+
runtime = __va(efi.systab->runtime);
efi.get_time = phys_get_time;
efi.set_time = phys_set_time;
diff --git a/arch/ia64/kernel/setup.c b/arch/ia64/kernel/setup.c
index 6206541f9e8..b86a072418a 100644
--- a/arch/ia64/kernel/setup.c
+++ b/arch/ia64/kernel/setup.c
@@ -59,6 +59,7 @@
#include <asm/setup.h>
#include <asm/smp.h>
#include <asm/system.h>
+#include <asm/tlbflush.h>
#include <asm/unistd.h>
#include <asm/hpsim.h>
@@ -948,9 +949,10 @@ cpu_init (void)
#endif
/* set ia64_ctx.max_rid to the maximum RID that is supported by all CPUs: */
- if (ia64_pal_vm_summary(NULL, &vmi) == 0)
+ if (ia64_pal_vm_summary(NULL, &vmi) == 0) {
max_ctx = (1U << (vmi.pal_vm_info_2_s.rid_size - 3)) - 1;
- else {
+ setup_ptcg_sem(vmi.pal_vm_info_2_s.max_purges, NPTCG_FROM_PAL);
+ } else {
printk(KERN_WARNING "cpu_init: PAL VM summary failed, assuming 18 RID bits\n");
max_ctx = (1U << 15) - 1; /* use architected minimum */
}
diff --git a/arch/ia64/mm/tlb.c b/arch/ia64/mm/tlb.c
index 3d8903f936a..d52ec4e8340 100644
--- a/arch/ia64/mm/tlb.c
+++ b/arch/ia64/mm/tlb.c
@@ -11,6 +11,9 @@
* Rohit Seth <rohit.seth@intel.com>
* Ken Chen <kenneth.w.chen@intel.com>
* Christophe de Dinechin <ddd@hp.com>: Avoid ptc.e on memory allocation
+ * Copyright (C) 2007 Intel Corp
+ * Fenghua Yu <fenghua.yu@intel.com>
+ * Add multiple ptc.g/ptc.ga instruction support in global tlb purge.
*/
#include <linux/module.h>
#include <linux/init.h>
@@ -27,6 +30,7 @@
#include <asm/tlbflush.h>
#include <asm/dma.h>
#include <asm/processor.h>
+#include <asm/sal.h>
#include <asm/tlb.h>
static struct {
@@ -90,14 +94,140 @@ wrap_mmu_context (struct mm_struct *mm)
local_flush_tlb_all();
}
+/*
+ * Implement "spinaphores" ... like counting semaphores, but they
+ * spin instead of sleeping. If there are ever any other users for
+ * this primitive it can be moved up to a spinaphore.h header.
+ */
+struct spinaphore {
+ atomic_t cur;
+};
+
+static inline void spinaphore_init(struct spinaphore *ss, int val)
+{
+ atomic_set(&ss->cur, val);
+}
+
+static inline void down_spin(struct spinaphore *ss)
+{
+ while (unlikely(!atomic_add_unless(&ss->cur, -1, 0)))
+ while (atomic_read(&ss->cur) == 0)
+ cpu_relax();
+}
+
+static inline void up_spin(struct spinaphore *ss)
+{
+ atomic_add(1, &ss->cur);
+}
+
+static struct spinaphore ptcg_sem;
+static u16 nptcg = 1;
+static int need_ptcg_sem = 1;
+static int toolatetochangeptcgsem = 0;
+
+/*
+ * Kernel parameter "nptcg=" overrides max number of concurrent global TLB
+ * purges which is reported from either PAL or SAL PALO.
+ *
+ * We don't have sanity checking for nptcg value. It's the user's responsibility
+ * for valid nptcg value on the platform. Otherwise, kernel may hang in some
+ * cases.
+ */
+static int __init
+set_nptcg(char *str)
+{
+ int value = 0;
+
+ get_option(&str, &value);
+ setup_ptcg_sem(value, NPTCG_FROM_KERNEL_PARAMETER);
+
+ return 1;
+}
+
+__setup("nptcg=", set_nptcg);
+
+/*
+ * Maximum number of simultaneous ptc.g purges in the system can
+ * be defined by PAL_VM_SUMMARY (in which case we should take
+ * the smallest value for any cpu in the system) or by the PAL
+ * override table (in which case we should ignore the value from
+ * PAL_VM_SUMMARY).
+ *
+ * Kernel parameter "nptcg=" overrides maximum number of simultanesous ptc.g
+ * purges defined in either PAL_VM_SUMMARY or PAL override table. In this case,
+ * we should ignore the value from either PAL_VM_SUMMARY or PAL override table.
+ *
+ * Complicating the logic here is the fact that num_possible_cpus()
+ * isn't fully setup until we start bringing cpus online.
+ */
+void
+setup_ptcg_sem(int max_purges, int nptcg_from)
+{
+ static int kp_override;
+ static int palo_override;
+ static int firstcpu = 1;
+
+ if (toolatetochangeptcgsem) {
+ BUG_ON(max_purges < nptcg);
+ return;
+ }
+
+ if (nptcg_from == NPTCG_FROM_KERNEL_PARAMETER) {
+ kp_override = 1;
+ nptcg = max_purges;
+ goto resetsema;
+ }
+ if (kp_override) {
+ need_ptcg_sem = num_possible_cpus() > nptcg;
+ return;
+ }
+
+ if (nptcg_from == NPTCG_FROM_PALO) {
+ palo_override = 1;
+
+ /* In PALO max_purges == 0 really means it! */
+ if (max_purges == 0)
+ panic("Whoa! Platform does not support global TLB purges.\n");
+ nptcg = max_purges;
+ if (nptcg == PALO_MAX_TLB_PURGES) {
+ need_ptcg_sem = 0;
+ return;
+ }
+ goto resetsema;
+ }
+ if (palo_override) {
+ if (nptcg != PALO_MAX_TLB_PURGES)
+ need_ptcg_sem = (num_possible_cpus() > nptcg);
+ return;
+ }
+
+ /* In PAL_VM_SUMMARY max_purges == 0 actually means 1 */
+ if (max_purges == 0) max_purges = 1;
+
+ if (firstcpu) {
+ nptcg = max_purges;
+ firstcpu = 0;
+ }
+ if (max_purges < nptcg)
+ nptcg = max_purges;
+ if (nptcg == PAL_MAX_PURGES) {
+ need_ptcg_sem = 0;
+ return;
+ } else
+ need_ptcg_sem = (num_possible_cpus() > nptcg);
+
+resetsema:
+ spinaphore_init(&ptcg_sem, max_purges);
+}
+
void
ia64_global_tlb_purge (struct mm_struct *mm, unsigned long start,
unsigned long end, unsigned long nbits)
{
- static DEFINE_SPINLOCK(ptcg_lock);
-
struct mm_struct *active_mm = current->active_mm;
+ toolatetochangeptcgsem = 1;
+
if (mm != active_mm) {
/* Restore region IDs for mm */
if (mm && active_mm) {
@@ -108,19 +238,20 @@ ia64_global_tlb_purge (struct mm_struct *mm, unsigned long start,
}
}
- /* HW requires global serialization of ptc.ga. */
- spin_lock(&ptcg_lock);
- {
- do {
- /*
- * Flush ALAT entries also.
- */
- ia64_ptcga(start, (nbits<<2));
- ia64_srlz_i();
- start += (1UL << nbits);
- } while (start < end);
- }
- spin_unlock(&ptcg_lock);
+ if (need_ptcg_sem)
+ down_spin(&ptcg_sem);
+
+ do {
+ /*
+ * Flush ALAT entries also.
+ */
+ ia64_ptcga(start, (nbits << 2));
+ ia64_srlz_i();
+ start += (1UL << nbits);
+ } while (start < end);
+
+ if (need_ptcg_sem)
+ up_spin(&ptcg_sem);
if (mm != active_mm) {
activate_context(active_mm);
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-12-22 17:35:48 +0000