| Message ID | 20190626213718.39423-2-jeremy.linton@arm.com (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
| Series | arm64: SPE ACPI enablement | expand |
On 2019/6/27 5:37, Jeremy Linton wrote: > The ACPI specification implies that the IDENTICAL flag should be > set on all non leaf nodes where the children are identical. > This means that we need to be searching for the last node with > the identical flag set rather than the first one. > > Since this flag is also dependent on the table revision, we > need to add a bit of extra code to verify the table revision, > and the next node's state in the traversal. Since we want to > avoid function pointers here, lets just special case > the IDENTICAL flag. > > Tested-by: Hanjun Gou <gouhanjun@huawei.com> This is wrong, my family name is Guo, and please correct my email address as well (for all the 4 patches). Thanks Hanjun
On Wed, Jun 26, 2019 at 11:37 PM Jeremy Linton <jeremy.linton@arm.com> wrote: > > The ACPI specification implies that the IDENTICAL flag should be > set on all non leaf nodes where the children are identical. > This means that we need to be searching for the last node with > the identical flag set rather than the first one. > > Since this flag is also dependent on the table revision, we > need to add a bit of extra code to verify the table revision, > and the next node's state in the traversal. Since we want to > avoid function pointers here, lets just special case > the IDENTICAL flag. > > Tested-by: Hanjun Gou <gouhanjun@huawei.com> > Reviewed-by: Sudeep Holla <sudeep.holla@arm.com> > Signed-off-by: Jeremy Linton <jeremy.linton@arm.com> Assuming that the Tested-by tag will be fixed: Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > --- > drivers/acpi/pptt.c | 35 +++++++++++++++++++++++++++++------ > 1 file changed, 29 insertions(+), 6 deletions(-) > > diff --git a/drivers/acpi/pptt.c b/drivers/acpi/pptt.c > index b72e6afaa8fb..05344413f199 100644 > --- a/drivers/acpi/pptt.c > +++ b/drivers/acpi/pptt.c > @@ -432,17 +432,40 @@ static void cache_setup_acpi_cpu(struct acpi_table_header *table, > } > } > > +static bool flag_identical(struct acpi_table_header *table_hdr, > + struct acpi_pptt_processor *cpu) > +{ > + struct acpi_pptt_processor *next; > + > + /* heterogeneous machines must use PPTT revision > 1 */ > + if (table_hdr->revision < 2) > + return false; > + > + /* Locate the last node in the tree with IDENTICAL set */ > + if (cpu->flags & ACPI_PPTT_ACPI_IDENTICAL) { > + next = fetch_pptt_node(table_hdr, cpu->parent); > + if (!(next && next->flags & ACPI_PPTT_ACPI_IDENTICAL)) > + return true; > + } > + > + return false; > +} > + > /* Passing level values greater than this will result in search termination */ > #define PPTT_ABORT_PACKAGE 0xFF > > -static struct acpi_pptt_processor *acpi_find_processor_package_id(struct acpi_table_header *table_hdr, > - struct acpi_pptt_processor *cpu, > - int level, int flag) > +static struct acpi_pptt_processor *acpi_find_processor_tag(struct acpi_table_header *table_hdr, > + struct acpi_pptt_processor *cpu, > + int level, int flag) > { > struct acpi_pptt_processor *prev_node; > > while (cpu && level) { > - if (cpu->flags & flag) > + /* special case the identical flag to find last identical */ > + if (flag == ACPI_PPTT_ACPI_IDENTICAL) { > + if (flag_identical(table_hdr, cpu)) > + break; > + } else if (cpu->flags & flag) > break; > pr_debug("level %d\n", level); > prev_node = fetch_pptt_node(table_hdr, cpu->parent); > @@ -480,8 +503,8 @@ static int topology_get_acpi_cpu_tag(struct acpi_table_header *table, > > cpu_node = acpi_find_processor_node(table, acpi_cpu_id); > if (cpu_node) { > - cpu_node = acpi_find_processor_package_id(table, cpu_node, > - level, flag); > + cpu_node = acpi_find_processor_tag(table, cpu_node, > + level, flag); > /* > * As per specification if the processor structure represents > * an actual processor, then ACPI processor ID must be valid. > -- > 2.21.0 >
diff --git a/drivers/acpi/pptt.c b/drivers/acpi/pptt.c index b72e6afaa8fb..05344413f199 100644 --- a/drivers/acpi/pptt.c +++ b/drivers/acpi/pptt.c @@ -432,17 +432,40 @@ static void cache_setup_acpi_cpu(struct acpi_table_header *table, } } +static bool flag_identical(struct acpi_table_header *table_hdr, + struct acpi_pptt_processor *cpu) +{ + struct acpi_pptt_processor *next; + + /* heterogeneous machines must use PPTT revision > 1 */ + if (table_hdr->revision < 2) + return false; + + /* Locate the last node in the tree with IDENTICAL set */ + if (cpu->flags & ACPI_PPTT_ACPI_IDENTICAL) { + next = fetch_pptt_node(table_hdr, cpu->parent); + if (!(next && next->flags & ACPI_PPTT_ACPI_IDENTICAL)) + return true; + } + + return false; +} + /* Passing level values greater than this will result in search termination */ #define PPTT_ABORT_PACKAGE 0xFF -static struct acpi_pptt_processor *acpi_find_processor_package_id(struct acpi_table_header *table_hdr, - struct acpi_pptt_processor *cpu, - int level, int flag) +static struct acpi_pptt_processor *acpi_find_processor_tag(struct acpi_table_header *table_hdr, + struct acpi_pptt_processor *cpu, + int level, int flag) { struct acpi_pptt_processor *prev_node; while (cpu && level) { - if (cpu->flags & flag) + /* special case the identical flag to find last identical */ + if (flag == ACPI_PPTT_ACPI_IDENTICAL) { + if (flag_identical(table_hdr, cpu)) + break; + } else if (cpu->flags & flag) break; pr_debug("level %d\n", level); prev_node = fetch_pptt_node(table_hdr, cpu->parent); @@ -480,8 +503,8 @@ static int topology_get_acpi_cpu_tag(struct acpi_table_header *table, cpu_node = acpi_find_processor_node(table, acpi_cpu_id); if (cpu_node) { - cpu_node = acpi_find_processor_package_id(table, cpu_node, - level, flag); + cpu_node = acpi_find_processor_tag(table, cpu_node, + level, flag); /* * As per specification if the processor structure represents * an actual processor, then ACPI processor ID must be valid.