[PATCH 2/3] tools/hvmloader: Replace LAPIC_ID() with cpu_to_apicid[]

[Alejandro Vallejo <alejandro.vallejo@xxxxxxxxx>]

Replace uses of the LAPIC_ID() macro with accesses to the
cpu_to_apicid[] lookup table. This table contains the APIC IDs of each
vCPU as probed at runtime rather than assuming a predefined relation.

Moved smp_initialise() ahead of apic_setup() in order to initialise
cpu_to_apicid ASAP and avoid using it uninitialised. Note that bringing
up the APs doesn't need the APIC in hvmloader becasue it always runs
virtualized and uses the PV interface.

Signed-off-by: Alejandro Vallejo <alejandro.vallejo@xxxxxxxxx>
---
Changes from v7 of the longer topology series:
  * Removed ASSERT() for the MP tables and merely skipped writing them
    if any vCPU has an APIC ID >=255.
---
 tools/firmware/hvmloader/config.h    | 3 ++-
 tools/firmware/hvmloader/hvmloader.c | 6 +++---
 tools/firmware/hvmloader/mp_tables.c | 2 +-
 tools/firmware/hvmloader/util.c      | 2 +-
 4 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/tools/firmware/hvmloader/config.h 
b/tools/firmware/hvmloader/config.h
index cd716bf39245..6e1da137d779 100644
--- a/tools/firmware/hvmloader/config.h
+++ b/tools/firmware/hvmloader/config.h
@@ -48,8 +48,9 @@ extern uint8_t ioapic_version;
 
 #define IOAPIC_ID           0x01
 
+extern uint32_t *cpu_to_apicid;
+
 #define LAPIC_BASE_ADDRESS  0xfee00000
-#define LAPIC_ID(vcpu_id)   ((vcpu_id) * 2)
 
 #define PCI_ISA_DEVFN       0x08    /* dev 1, fn 0 */
 #define PCI_ISA_IRQ_MASK    0x0c20U /* ISA IRQs 5,10,11 are PCI connected */
diff --git a/tools/firmware/hvmloader/hvmloader.c 
b/tools/firmware/hvmloader/hvmloader.c
index f8af88fabf24..4e330fc1e241 100644
--- a/tools/firmware/hvmloader/hvmloader.c
+++ b/tools/firmware/hvmloader/hvmloader.c
@@ -224,7 +224,7 @@ static void apic_setup(void)
 
     /* 8259A ExtInts are delivered through IOAPIC pin 0 (Virtual Wire Mode). */
     ioapic_write(0x10, APIC_DM_EXTINT);
-    ioapic_write(0x11, SET_APIC_ID(LAPIC_ID(0)));
+    ioapic_write(0x11, SET_APIC_ID(cpu_to_apicid[0]));
 }
 
 struct bios_info {
@@ -341,11 +341,11 @@ int main(void)
 
     printf("CPU speed is %u MHz\n", get_cpu_mhz());
 
+    smp_initialise();
+
     apic_setup();
     pci_setup();
 
-    smp_initialise();
-
     perform_tests();
 
     if ( bios->bios_info_setup )
diff --git a/tools/firmware/hvmloader/mp_tables.c 
b/tools/firmware/hvmloader/mp_tables.c
index 77d3010406d0..3c93a5c947d9 100644
--- a/tools/firmware/hvmloader/mp_tables.c
+++ b/tools/firmware/hvmloader/mp_tables.c
@@ -199,7 +199,7 @@ static void fill_mp_config_table(struct mp_config_table 
*mpct, int length)
 static void fill_mp_proc_entry(struct mp_proc_entry *mppe, int vcpu_id)
 {
     mppe->type = ENTRY_TYPE_PROCESSOR;
-    mppe->lapic_id = LAPIC_ID(vcpu_id);
+    mppe->lapic_id = cpu_to_apicid[vcpu_id];
     mppe->lapic_version = 0x11;
     mppe->cpu_flags = CPU_FLAG_ENABLED;
     if ( vcpu_id == 0 )
diff --git a/tools/firmware/hvmloader/util.c b/tools/firmware/hvmloader/util.c
index d3b3f9038e64..2d07ce129013 100644
--- a/tools/firmware/hvmloader/util.c
+++ b/tools/firmware/hvmloader/util.c
@@ -827,7 +827,7 @@ static void acpi_mem_free(struct acpi_ctxt *ctxt,
 
 static uint32_t acpi_lapic_id(unsigned cpu)
 {
-    return LAPIC_ID(cpu);
+    return cpu_to_apicid[cpu];
 }
 
 void hvmloader_acpi_build_tables(struct acpi_config *config,
-- 
2.48.1