I should warn you that FADT version numbers are notoriously unreliable; In fact, in ACPICA we were eventually forced to abandon them entirely. We use the actual size of the FADT instead.
Bob
-----Original Message----- From: Hanjun Guo [mailto:hanjun.guo@linaro.org] Sent: Tuesday, August 19, 2014 5:14 AM To: Mark Rutland Cc: Catalin Marinas; Rafael J. Wysocki; graeme.gregory@linaro.org; Arnd Bergmann; Olof Johansson; grant.likely@linaro.org; Sudeep Holla; Will Deacon; Jason Cooper; Marc Zyngier; Bjorn Helgaas; Daniel Lezcano; Mark Brown; Rob Herring; Robert Richter; Zheng, Lv; Moore, Robert; Lorenzo Pieralisi; Liviu Dudau; Randy Dunlap; Charles Garcia-Tobin; linux- acpi@vger.kernel.org; linux-arm-kernel@lists.infradead.org; linux- kernel@vger.kernel.org; linaro-acpi@lists.linaro.org Subject: Re: [PATCH v2 05/18] ARM64 / ACPI: Parse FADT table to get PSCI flags for PSCI init
On 2014-8-19 19:10, Mark Rutland wrote:
@@ -47,6 +49,26 @@ void __init __acpi_unmap_table(char *map, unsigned
long size)
early_memunmap(map, size); }
+static int __init acpi_parse_fadt(struct acpi_table_header *table) +{
- struct acpi_table_fadt *fadt = (struct acpi_table_fadt
*)table;
- /*
* Revision in table header is the FADT Major version,
* and there is a minor version of FADT which was introduced
* by ACPI 5.1, we only deal with ACPI 5.1 or higher version
* to get arm boot flags, or we will disable ACPI.
*/
- if (table->revision < 5 || fadt->minor_revision < 1) {
If we ever get revision 6.0, this would trigger.
Yes, good catch, actually I already fixed that in my local git repo,
if (table->revision > 5 ||
(table->revision == 5 && fadt->minor_revision >= 1)) {
return 0;
} else {
pr_info("FADT revision is %d.%d, no PSCI support,
- should be 5.1
or higher\n",
table->revision, fadt->minor_revision);
disable_acpi();
return -EINVAL;
}
Given you return in the first path, you don't need the remaining code to live in an else block.
Agreed, I will update it, and move disable_acpi() outside this function and keep it in one place as Sudeep suggested.
Thanks Hanjun