On Fri, May 06, 2022 at 09:55:50PM +0100, Nikos Nikoleris wrote:
> In systems with ACPI support and when a DT is not provided, we can use
> the MADTs to discover the number of CPUs and their corresponding MIDR.
> This change implements this but retains the default behavior; we check
> if a valid DT is provided, if not, we try to discover the cores in the
> system using ACPI.
>
> Signed-off-by: Nikos Nikoleris <nikos.nikoleris@xxxxxxx>
> ---
> lib/acpi.h | 64 +++++++++++++++++++++++++++++++++++++++++++++++++
> lib/acpi.c | 21 ++++++++++++++++
> lib/arm/setup.c | 25 ++++++++++++++++---
> 3 files changed, 107 insertions(+), 3 deletions(-)
>
> diff --git a/lib/acpi.h b/lib/acpi.h
> index 297ad87..55de54a 100644
> --- a/lib/acpi.h
> +++ b/lib/acpi.h
> @@ -16,6 +16,7 @@
> #define XSDT_SIGNATURE ACPI_SIGNATURE('X','S','D','T')
> #define FACP_SIGNATURE ACPI_SIGNATURE('F','A','C','P')
> #define FACS_SIGNATURE ACPI_SIGNATURE('F','A','C','S')
> +#define MADT_SIGNATURE ACPI_SIGNATURE('A','P','I','C')
> #define SPCR_SIGNATURE ACPI_SIGNATURE('S','P','C','R')
> #define GTDT_SIGNATURE ACPI_SIGNATURE('G','T','D','T')
>
> @@ -149,6 +150,67 @@ struct facs_descriptor_rev1
> u8 reserved3 [40]; /* Reserved - must be zero */
> } __attribute__ ((packed));
>
> +struct acpi_table_madt {
> + ACPI_TABLE_HEADER_DEF /* ACPI common table header */
> + u32 address; /* Physical address of local APIC */
nit: some whitespace issues
> + u32 flags;
> +} __attribute__ ((packed));
> +
> +struct acpi_subtable_header {
> + u8 type;
> + u8 length;
> +} __attribute__ ((packed));
> +
> +typedef int (*acpi_table_handler)(struct acpi_subtable_header *header);
> +
> +/* 11: Generic interrupt - GICC (ACPI 5.0 + ACPI 6.0 + ACPI 6.3 changes) */
> +
> +struct acpi_madt_generic_interrupt {
> + u8 type;
> + u8 length;
> + u16 reserved; /* reserved - must be zero */
> + u32 cpu_interface_number;
> + u32 uid;
> + u32 flags;
> + u32 parking_version;
> + u32 performance_interrupt;
> + u64 parked_address;
> + u64 base_address;
> + u64 gicv_base_address;
> + u64 gich_base_address;
> + u32 vgic_interrupt;
> + u64 gicr_base_address;
> + u64 arm_mpidr;
> + u8 efficiency_class;
> + u8 reserved2[1];
> + u16 spe_interrupt; /* ACPI 6.3 */
> +} __attribute__ ((packed));
> +
> +/* Values for MADT subtable type in struct acpi_subtable_header */
> +
> +enum acpi_madt_type {
> + ACPI_MADT_TYPE_LOCAL_APIC = 0,
> + ACPI_MADT_TYPE_IO_APIC = 1,
> + ACPI_MADT_TYPE_INTERRUPT_OVERRIDE = 2,
> + ACPI_MADT_TYPE_NMI_SOURCE = 3,
> + ACPI_MADT_TYPE_LOCAL_APIC_NMI = 4,
> + ACPI_MADT_TYPE_LOCAL_APIC_OVERRIDE = 5,
> + ACPI_MADT_TYPE_IO_SAPIC = 6,
> + ACPI_MADT_TYPE_LOCAL_SAPIC = 7,
> + ACPI_MADT_TYPE_INTERRUPT_SOURCE = 8,
> + ACPI_MADT_TYPE_LOCAL_X2APIC = 9,
> + ACPI_MADT_TYPE_LOCAL_X2APIC_NMI = 10,
> + ACPI_MADT_TYPE_GENERIC_INTERRUPT = 11,
> + ACPI_MADT_TYPE_GENERIC_DISTRIBUTOR = 12,
> + ACPI_MADT_TYPE_GENERIC_MSI_FRAME = 13,
> + ACPI_MADT_TYPE_GENERIC_REDISTRIBUTOR = 14,
> + ACPI_MADT_TYPE_GENERIC_TRANSLATOR = 15,
> + ACPI_MADT_TYPE_RESERVED = 16 /* 16 and greater are reserved */
> +};
> +
> +/* MADT Local APIC flags */
> +#define ACPI_MADT_ENABLED (1) /* 00: Processor is usable if set */
> +
> struct spcr_descriptor {
> ACPI_TABLE_HEADER_DEF /* ACPI common table header */
> u8 interface_type; /* 0=full 16550, 1=subset of 16550 */
> @@ -192,5 +254,7 @@ struct acpi_table_gtdt {
>
> void set_efi_rsdp(struct rsdp_descriptor *rsdp);
> void* find_acpi_table_addr(u32 sig);
> +void acpi_table_parse_madt(enum acpi_madt_type mtype,
> + acpi_table_handler handler);
nit: unnecessary line break
>
> #endif
> diff --git a/lib/acpi.c b/lib/acpi.c
> index e8440ae..ad3ae8d 100644
> --- a/lib/acpi.c
> +++ b/lib/acpi.c
> @@ -101,3 +101,24 @@ void* find_acpi_table_addr(u32 sig)
>
> return NULL;
> }
> +
> +void acpi_table_parse_madt(enum acpi_madt_type mtype,
> + acpi_table_handler handler)
> +{
> + struct acpi_table_madt *madt;
> + void *end;
> +
> + madt = find_acpi_table_addr(MADT_SIGNATURE);
> + assert(madt);
> +
> + struct acpi_subtable_header *header =
> + (void *)(ulong)madt + sizeof(struct acpi_table_madt);
nit: unnecessary line break
> + end = (void *)((ulong)madt + madt->length);
> +
> + while ((void *)header < end) {
> + if (header->type == mtype)
> + handler(header);
> +
> + header = (void *)(ulong)header + header->length;
> + }
> +}
> diff --git a/lib/arm/setup.c b/lib/arm/setup.c
> index 1572c64..3c24c75 100644
> --- a/lib/arm/setup.c
> +++ b/lib/arm/setup.c
> @@ -13,6 +13,7 @@
> #include <libcflat.h>
> #include <libfdt/libfdt.h>
> #include <devicetree.h>
> +#include <acpi.h>
> #include <alloc.h>
> #include <alloc_phys.h>
> #include <alloc_page.h>
> @@ -55,7 +56,7 @@ int mpidr_to_cpu(uint64_t mpidr)
> return -1;
> }
>
> -static void cpu_set(int fdtnode __unused, u64 regval, void *info __unused)
> +static void cpu_set_fdt(int fdtnode __unused, u64 regval, void *info __unused)
> {
> int cpu = nr_cpus++;
>
> @@ -65,13 +66,31 @@ static void cpu_set(int fdtnode __unused, u64 regval, void *info __unused)
> set_cpu_present(cpu, true);
> }
>
> +static int cpu_set_acpi(struct acpi_subtable_header *header)
> +{
> + int cpu = nr_cpus++;
> + struct acpi_madt_generic_interrupt *gicc = (void *)header;
> +
> + assert_msg(cpu < NR_CPUS, "Number cpus exceeds maximum supported (%d).", NR_CPUS);
> +
> + cpus[cpu] = gicc->arm_mpidr;
> + set_cpu_present(cpu, true);
> +
> + return 0;
> +}
> +
> static void cpu_init(void)
> {
> int ret;
>
> nr_cpus = 0;
> - ret = dt_for_each_cpu_node(cpu_set, NULL);
> - assert(ret == 0);
> + if (dt_available()) {
> + ret = dt_for_each_cpu_node(cpu_set_fdt, NULL);
> + assert(ret == 0);
> + } else
> + acpi_table_parse_madt(ACPI_MADT_TYPE_GENERIC_INTERRUPT,
> + cpu_set_acpi);
nit: unnecessary line break and please balance the {} on the else
> +
> set_cpu_online(0, true);
> }
>
> --
> 2.25.1
>
I looked ahead and see you make a lot more use of acpi_table_parse_madt()
when adding the gic support.
Reviewed-by: Andrew Jones <drjones@xxxxxxxxxx>
Thanks,
drew
