[V5,08/21] RISC-V: ACPI: Cache and retrieve the RINTC structure

Commit Message

Sunil V L May 8, 2023, 11:52 a.m. UTC

RINTC structures in the MADT provide mapping between the hartid
and the CPU. This is required many times even at run time like
cpuinfo. So, instead of parsing the ACPI table every time, cache
the RINTC structures and provide a function to get the correct
RINTC structure for a given cpu.

Signed-off-by: Sunil V L <[e-mail]>
Acked-by: Rafael J. Wysocki <[e-mail]>
---
 arch/riscv/include/asm/acpi.h | 10 ++++++++
 arch/riscv/kernel/acpi.c      | 45 +++++++++++++++++++++++++++++++++++
 arch/riscv/kernel/setup.c     |  4 ++++
 3 files changed, 59 insertions(+)

Comments

Conor Dooley May 9, 2023, 5:50 p.m. UTC | #1

Hey Sunil,

On Mon, May 08, 2023 at 05:22:24PM +0530, Sunil V L wrote:
> RINTC structures in the MADT provide mapping between the hartid
> and the CPU. This is required many times even at run time like
> cpuinfo. So, instead of parsing the ACPI table every time, cache
> the RINTC structures and provide a function to get the correct
> RINTC structure for a given cpu.
> 
> Signed-off-by: Sunil V L <[e-mail]>
> Acked-by: Rafael J. Wysocki <[e-mail]>

From this patch until "RISC-V: Add ACPI initialization in
setup_arch()" (which is 19/21), the series fails to build.

allmodconfig, clang-16:
../arch/riscv/include/asm/acpi.h:22:23: error: unknown type name 'acpi_physical_address'; did you mean 'efi_physical_addr_t'?
../arch/riscv/include/asm/acpi.h:22:51: error: unknown type name 'acpi_size'

rv32_defconfig, clang-16:
arch/riscv/kernel/setup.c:297:7: error: use of undeclared identifier 'acpi_disabled'; did you mean '__cpu_disable'?
arch/riscv/kernel/setup.c:297:7: warning: address of function '__cpu_disable' will always evaluate to 'true' [-Wpointer-bool-conversion]

I ballsed up a toolchain upgrade to gcc-13, so the whole series is
showing build issues on patchwork for the gcc configurations:
https://patchwork.kernel.org/project/linux-riscv/list/?series=745787

However, I suspect that the same patches that fail for clang-16 will
fail for gcc-13 too, once I have fixed that!

Cheers,
Conor.

> ---
>  arch/riscv/include/asm/acpi.h | 10 ++++++++
>  arch/riscv/kernel/acpi.c      | 45 +++++++++++++++++++++++++++++++++++
>  arch/riscv/kernel/setup.c     |  4 ++++
>  3 files changed, 59 insertions(+)
> 
> diff --git a/arch/riscv/include/asm/acpi.h b/arch/riscv/include/asm/acpi.h
> index 9be52b6ffae1..6519529c8bdf 100644
> --- a/arch/riscv/include/asm/acpi.h
> +++ b/arch/riscv/include/asm/acpi.h
> @@ -59,6 +59,16 @@ static inline bool acpi_has_cpu_in_madt(void)
>  
>  static inline void arch_fix_phys_package_id(int num, u32 slot) { }
>  
> +void acpi_init_rintc_map(void);
> +struct acpi_madt_rintc *acpi_cpu_get_madt_rintc(int cpu);
> +u32 get_acpi_id_for_cpu(int cpu);
> +#else
> +static inline void acpi_init_rintc_map(void) { }
> +static inline struct acpi_madt_rintc *acpi_cpu_get_madt_rintc(int cpu)
> +{
> +	return NULL;
> +}
> +
>  #endif /* CONFIG_ACPI */
>  
>  #endif /*_ASM_ACPI_H*/
> diff --git a/arch/riscv/kernel/acpi.c b/arch/riscv/kernel/acpi.c
> index 81d448c41714..89e142611c84 100644
> --- a/arch/riscv/kernel/acpi.c
> +++ b/arch/riscv/kernel/acpi.c
> @@ -24,6 +24,51 @@ EXPORT_SYMBOL(acpi_disabled);
>  int acpi_pci_disabled = 1;	/* skip ACPI PCI scan and IRQ initialization */
>  EXPORT_SYMBOL(acpi_pci_disabled);
>  
> +static struct acpi_madt_rintc cpu_madt_rintc[NR_CPUS];
> +
> +static int acpi_parse_madt_rintc(union acpi_subtable_headers *header, const unsigned long end)
> +{
> +	struct acpi_madt_rintc *rintc = (struct acpi_madt_rintc *)header;
> +	int cpuid;
> +
> +	if (!(rintc->flags & ACPI_MADT_ENABLED))
> +		return 0;
> +
> +	cpuid = riscv_hartid_to_cpuid(rintc->hart_id);
> +	/*
> +	 * When CONFIG_SMP is disabled, mapping won't be created for
> +	 * all cpus.
> +	 * CPUs more than num_possible_cpus, will be ignored.
> +	 */
> +	if (cpuid >= 0 && cpuid < num_possible_cpus())
> +		cpu_madt_rintc[cpuid] = *rintc;
> +
> +	return 0;
> +}
> +
> +/*
> + * Instead of parsing (and freeing) the ACPI table, cache
> + * the RINTC structures since they are frequently used
> + * like in  cpuinfo.
> + */
> +void __init acpi_init_rintc_map(void)
> +{
> +	if (acpi_table_parse_madt(ACPI_MADT_TYPE_RINTC, acpi_parse_madt_rintc, 0) <= 0) {
> +		pr_err("No valid RINTC entries exist\n");
> +		BUG();
> +	}
> +}
> +
> +struct acpi_madt_rintc *acpi_cpu_get_madt_rintc(int cpu)
> +{
> +	return &cpu_madt_rintc[cpu];
> +}
> +
> +u32 get_acpi_id_for_cpu(int cpu)
> +{
> +	return acpi_cpu_get_madt_rintc(cpu)->uid;
> +}
> +
>  /*
>   * __acpi_map_table() will be called before paging_init(), so early_ioremap()
>   * or early_memremap() should be called here to for ACPI table mapping.
> diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c
> index 9fb839074e16..a44c7fcde12f 100644
> --- a/arch/riscv/kernel/setup.c
> +++ b/arch/riscv/kernel/setup.c
> @@ -21,6 +21,7 @@
>  #include <linux/efi.h>
>  #include <linux/crash_dump.h>
>  
> +#include <asm/acpi.h>
>  #include <asm/alternative.h>
>  #include <asm/cacheflush.h>
>  #include <asm/cpu_ops.h>
> @@ -293,6 +294,9 @@ void __init setup_arch(char **cmdline_p)
>  	setup_smp();
>  #endif
>  
> +	if (!acpi_disabled)
> +		acpi_init_rintc_map();
> +
>  	riscv_init_cbo_blocksizes();
>  	riscv_fill_hwcap();
>  	apply_boot_alternatives();
> -- 
> 2.34.1
>

Sunil V L May 10, 2023, 3:46 a.m. UTC | #2

Hi Conor,

On Tue, May 09, 2023 at 06:50:07PM +0100, Conor Dooley wrote:
> Hey Sunil,
> 
> On Mon, May 08, 2023 at 05:22:24PM +0530, Sunil V L wrote:
> > RINTC structures in the MADT provide mapping between the hartid
> > and the CPU. This is required many times even at run time like
> > cpuinfo. So, instead of parsing the ACPI table every time, cache
> > the RINTC structures and provide a function to get the correct
> > RINTC structure for a given cpu.
> > 
> > Signed-off-by: Sunil V L <[e-mail]>
> > Acked-by: Rafael J. Wysocki <[e-mail]>
> 
> From this patch until "RISC-V: Add ACPI initialization in
> setup_arch()" (which is 19/21), the series fails to build.
> 
> allmodconfig, clang-16:
> ../arch/riscv/include/asm/acpi.h:22:23: error: unknown type name 'acpi_physical_address'; did you mean 'efi_physical_addr_t'?
> ../arch/riscv/include/asm/acpi.h:22:51: error: unknown type name 'acpi_size'
> 
> rv32_defconfig, clang-16:
> arch/riscv/kernel/setup.c:297:7: error: use of undeclared identifier 'acpi_disabled'; did you mean '__cpu_disable'?
> arch/riscv/kernel/setup.c:297:7: warning: address of function '__cpu_disable' will always evaluate to 'true' [-Wpointer-bool-conversion]
>
> I ballsed up a toolchain upgrade to gcc-13, so the whole series is
> showing build issues on patchwork for the gcc configurations:
> https://patchwork.kernel.org/project/linux-riscv/list/?series=745787
> 
> However, I suspect that the same patches that fail for clang-16 will
> fail for gcc-13 too, once I have fixed that!
> 
My bad. It is a commit order issue. Let me fix it.

Thanks!
Sunil

Patch

diff --git a/arch/riscv/include/asm/acpi.h b/arch/riscv/include/asm/acpi.h
index 9be52b6ffae1..6519529c8bdf 100644
--- a/arch/riscv/include/asm/acpi.h
+++ b/arch/riscv/include/asm/acpi.h
@@ -59,6 +59,16 @@  static inline bool acpi_has_cpu_in_madt(void)
 
 static inline void arch_fix_phys_package_id(int num, u32 slot) { }
 
+void acpi_init_rintc_map(void);
+struct acpi_madt_rintc *acpi_cpu_get_madt_rintc(int cpu);
+u32 get_acpi_id_for_cpu(int cpu);
+#else
+static inline void acpi_init_rintc_map(void) { }
+static inline struct acpi_madt_rintc *acpi_cpu_get_madt_rintc(int cpu)
+{
+	return NULL;
+}
+
 #endif /* CONFIG_ACPI */
 
 #endif /*_ASM_ACPI_H*/
diff --git a/arch/riscv/kernel/acpi.c b/arch/riscv/kernel/acpi.c
index 81d448c41714..89e142611c84 100644
--- a/arch/riscv/kernel/acpi.c
+++ b/arch/riscv/kernel/acpi.c
@@ -24,6 +24,51 @@  EXPORT_SYMBOL(acpi_disabled);
 int acpi_pci_disabled = 1;	/* skip ACPI PCI scan and IRQ initialization */
 EXPORT_SYMBOL(acpi_pci_disabled);
 
+static struct acpi_madt_rintc cpu_madt_rintc[NR_CPUS];
+
+static int acpi_parse_madt_rintc(union acpi_subtable_headers *header, const unsigned long end)
+{
+	struct acpi_madt_rintc *rintc = (struct acpi_madt_rintc *)header;
+	int cpuid;
+
+	if (!(rintc->flags & ACPI_MADT_ENABLED))
+		return 0;
+
+	cpuid = riscv_hartid_to_cpuid(rintc->hart_id);
+	/*
+	 * When CONFIG_SMP is disabled, mapping won't be created for
+	 * all cpus.
+	 * CPUs more than num_possible_cpus, will be ignored.
+	 */
+	if (cpuid >= 0 && cpuid < num_possible_cpus())
+		cpu_madt_rintc[cpuid] = *rintc;
+
+	return 0;
+}
+
+/*
+ * Instead of parsing (and freeing) the ACPI table, cache
+ * the RINTC structures since they are frequently used
+ * like in  cpuinfo.
+ */
+void __init acpi_init_rintc_map(void)
+{
+	if (acpi_table_parse_madt(ACPI_MADT_TYPE_RINTC, acpi_parse_madt_rintc, 0) <= 0) {
+		pr_err("No valid RINTC entries exist\n");
+		BUG();
+	}
+}
+
+struct acpi_madt_rintc *acpi_cpu_get_madt_rintc(int cpu)
+{
+	return &cpu_madt_rintc[cpu];
+}
+
+u32 get_acpi_id_for_cpu(int cpu)
+{
+	return acpi_cpu_get_madt_rintc(cpu)->uid;
+}
+
 /*
  * __acpi_map_table() will be called before paging_init(), so early_ioremap()
  * or early_memremap() should be called here to for ACPI table mapping.
diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c
index 9fb839074e16..a44c7fcde12f 100644
--- a/arch/riscv/kernel/setup.c
+++ b/arch/riscv/kernel/setup.c
@@ -21,6 +21,7 @@ 
 #include <linux/efi.h>
 #include <linux/crash_dump.h>
 
+#include <asm/acpi.h>
 #include <asm/alternative.h>
 #include <asm/cacheflush.h>
 #include <asm/cpu_ops.h>
@@ -293,6 +294,9 @@  void __init setup_arch(char **cmdline_p)
 	setup_smp();
 #endif
 
+	if (!acpi_disabled)
+		acpi_init_rintc_map();
+
 	riscv_init_cbo_blocksizes();
 	riscv_fill_hwcap();
 	apply_boot_alternatives();