linux/include/asm-x86/mach-summit/mach_apic.h
Maciej W. Rozycki 593f4a788e x86: APIC: remove apic_write_around(); use alternatives
Use alternatives to select the workaround for the 11AP Pentium erratum
for the affected steppings on the fly rather than build time.  Remove the
X86_GOOD_APIC configuration option and replace all the calls to
apic_write_around() with plain apic_write(), protecting accesses to the
ESR as appropriate due to the 3AP Pentium erratum.  Remove
apic_read_around() and all its invocations altogether as not needed.
Remove apic_write_atomic() and all its implementing backends.  The use of
ASM_OUTPUT2() is not strictly needed for input constraints, but I have
used it for readability's sake.

I had the feeling no one else was brave enough to do it, so I went ahead
and here it is.  Verified by checking the generated assembly and tested
with both a 32-bit and a 64-bit configuration, also with the 11AP
"feature" forced on and verified with gdb on /proc/kcore to work as
expected (as an 11AP machines are quite hard to get hands on these days).
Some script complained about the use of "volatile", but apic_write() needs
it for the same reason and is effectively a replacement for writel(), so I
have disregarded it.

I am not sure what the policy wrt defconfig files is, they are generated
and there is risk of a conflict resulting from an unrelated change, so I
have left changes to them out.  The option will get removed from them at
the next run.

Some testing with machines other than mine will be needed to avoid some
stupid mistake, but despite its volume, the change is not really that
intrusive, so I am fairly confident that because it works for me, it will
everywhere.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-18 12:51:21 +02:00

186 lines
4.4 KiB
C

#ifndef __ASM_MACH_APIC_H
#define __ASM_MACH_APIC_H
#include <asm/smp.h>
#define esr_disable (1)
#define NO_BALANCE_IRQ (0)
/* In clustered mode, the high nibble of APIC ID is a cluster number.
* The low nibble is a 4-bit bitmap. */
#define XAPIC_DEST_CPUS_SHIFT 4
#define XAPIC_DEST_CPUS_MASK ((1u << XAPIC_DEST_CPUS_SHIFT) - 1)
#define XAPIC_DEST_CLUSTER_MASK (XAPIC_DEST_CPUS_MASK << XAPIC_DEST_CPUS_SHIFT)
#define APIC_DFR_VALUE (APIC_DFR_CLUSTER)
static inline cpumask_t target_cpus(void)
{
/* CPU_MASK_ALL (0xff) has undefined behaviour with
* dest_LowestPrio mode logical clustered apic interrupt routing
* Just start on cpu 0. IRQ balancing will spread load
*/
return cpumask_of_cpu(0);
}
#define TARGET_CPUS (target_cpus())
#define INT_DELIVERY_MODE (dest_LowestPrio)
#define INT_DEST_MODE 1 /* logical delivery broadcast to all procs */
static inline unsigned long check_apicid_used(physid_mask_t bitmap, int apicid)
{
return 0;
}
/* we don't use the phys_cpu_present_map to indicate apicid presence */
static inline unsigned long check_apicid_present(int bit)
{
return 1;
}
#define apicid_cluster(apicid) ((apicid) & XAPIC_DEST_CLUSTER_MASK)
extern u8 cpu_2_logical_apicid[];
static inline void init_apic_ldr(void)
{
unsigned long val, id;
int count = 0;
u8 my_id = (u8)hard_smp_processor_id();
u8 my_cluster = (u8)apicid_cluster(my_id);
#ifdef CONFIG_SMP
u8 lid;
int i;
/* Create logical APIC IDs by counting CPUs already in cluster. */
for (count = 0, i = NR_CPUS; --i >= 0; ) {
lid = cpu_2_logical_apicid[i];
if (lid != BAD_APICID && apicid_cluster(lid) == my_cluster)
++count;
}
#endif
/* We only have a 4 wide bitmap in cluster mode. If a deranged
* BIOS puts 5 CPUs in one APIC cluster, we're hosed. */
BUG_ON(count >= XAPIC_DEST_CPUS_SHIFT);
id = my_cluster | (1UL << count);
apic_write(APIC_DFR, APIC_DFR_VALUE);
val = apic_read(APIC_LDR) & ~APIC_LDR_MASK;
val |= SET_APIC_LOGICAL_ID(id);
apic_write(APIC_LDR, val);
}
static inline int multi_timer_check(int apic, int irq)
{
return 0;
}
static inline int apic_id_registered(void)
{
return 1;
}
static inline void setup_apic_routing(void)
{
printk("Enabling APIC mode: Summit. Using %d I/O APICs\n",
nr_ioapics);
}
static inline int apicid_to_node(int logical_apicid)
{
#ifdef CONFIG_SMP
return apicid_2_node[hard_smp_processor_id()];
#else
return 0;
#endif
}
/* Mapping from cpu number to logical apicid */
static inline int cpu_to_logical_apicid(int cpu)
{
#ifdef CONFIG_SMP
if (cpu >= NR_CPUS)
return BAD_APICID;
return (int)cpu_2_logical_apicid[cpu];
#else
return logical_smp_processor_id();
#endif
}
static inline int cpu_present_to_apicid(int mps_cpu)
{
if (mps_cpu < NR_CPUS)
return (int)per_cpu(x86_bios_cpu_apicid, mps_cpu);
else
return BAD_APICID;
}
static inline physid_mask_t ioapic_phys_id_map(physid_mask_t phys_id_map)
{
/* For clustered we don't have a good way to do this yet - hack */
return physids_promote(0x0F);
}
static inline physid_mask_t apicid_to_cpu_present(int apicid)
{
return physid_mask_of_physid(0);
}
static inline void setup_portio_remap(void)
{
}
static inline int check_phys_apicid_present(int boot_cpu_physical_apicid)
{
return 1;
}
static inline void enable_apic_mode(void)
{
}
static inline unsigned int cpu_mask_to_apicid(cpumask_t cpumask)
{
int num_bits_set;
int cpus_found = 0;
int cpu;
int apicid;
num_bits_set = cpus_weight(cpumask);
/* Return id to all */
if (num_bits_set == NR_CPUS)
return (int) 0xFF;
/*
* The cpus in the mask must all be on the apic cluster. If are not
* on the same apicid cluster return default value of TARGET_CPUS.
*/
cpu = first_cpu(cpumask);
apicid = cpu_to_logical_apicid(cpu);
while (cpus_found < num_bits_set) {
if (cpu_isset(cpu, cpumask)) {
int new_apicid = cpu_to_logical_apicid(cpu);
if (apicid_cluster(apicid) !=
apicid_cluster(new_apicid)){
printk ("%s: Not a valid mask!\n",__FUNCTION__);
return 0xFF;
}
apicid = apicid | new_apicid;
cpus_found++;
}
cpu++;
}
return apicid;
}
/* cpuid returns the value latched in the HW at reset, not the APIC ID
* register's value. For any box whose BIOS changes APIC IDs, like
* clustered APIC systems, we must use hard_smp_processor_id.
*
* See Intel's IA-32 SW Dev's Manual Vol2 under CPUID.
*/
static inline u32 phys_pkg_id(u32 cpuid_apic, int index_msb)
{
return hard_smp_processor_id() >> index_msb;
}
#endif /* __ASM_MACH_APIC_H */