Revert "arm_pmu: acpi: spe: Add initial MADT/SPE probing"

hulk inclusion
category: feature
bugzilla: 16072
CVE: NA
---------------------------

This reverts commit 556b16f5ad7e910c3784bb02b33c2af6ca9c9a4b.
In Linux 5.3.0, SPE ACPI enablement has been upstreamed. SPE patches
in hulk-4.19 are the old version, and they need to be reverted
to the mainline version.
Signed-off-by: NHongbo Yao <yaohongbo@huawei.com>
Reviewed-by: NHanjun Guo <guohanjun@huawei.com>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>

arch/arm64/include/asm/acpi.h

@@ -40,10 +40,6 @@
 	(!(entry) || (entry)->header.length < ACPI_MADT_GICC_MIN_LENGTH || \
 	(unsigned long)(entry) + (entry)->header.length > (end))
 
-#define ACPI_MADT_GICC_SPE  (ACPI_OFFSET(struct acpi_madt_generic_interrupt, \
-				 spe_overflow_interrupt) + sizeof(u16))
-
-
 /* Basic configuration for ACPI */
 #ifdef	CONFIG_ACPI
 pgprot_t __acpi_get_mem_attribute(phys_addr_t addr);

drivers/perf/arm_pmu_acpi.c

@@ -74,82 +74,6 @@ static void arm_pmu_acpi_unregister_irq(int cpu)
 	acpi_unregister_gsi(gsi);
 }
 
-static struct resource spe_resources[] = {
-	{
-		/* irq */
-		.flags          = IORESOURCE_IRQ,
-	}
-};
-
-static struct platform_device spe_dev = {
-	.name = "arm,spe-v1",
-	.id = -1,
-	.resource = spe_resources,
-	.num_resources = ARRAY_SIZE(spe_resources)
-};
-
-/*
- * For lack of a better place lets just hook the
- * normal PMU MADT walk and create a SPE device if
- * we detect a recent MADT with a homogeneous PPI mapping
- */
-static int arm_spe_acpi_parse_irqs(void)
-{
-	int cpu, ret, irq;
-	u32 flags, gsi;
-	bool first = true;
-
-	struct acpi_madt_generic_interrupt *gicc;
-
-	/*
-	 * sanity check all the GICC tables for the same interrupt number
-	 * for now we only support homogeneous ACPI/SPE machines.
-	 */
-	for_each_possible_cpu(cpu) {
-		gicc = acpi_cpu_get_madt_gicc(cpu);
-
-		if (gicc->header.length < ACPI_MADT_GICC_SPE)
-			return -ENODEV;
-
-		if (first) {
-			gsi = gicc->spe_overflow_interrupt;
-			if (!gsi)
-				return -ENODEV;
-			first = false;
-		} else if (gsi != gicc->spe_overflow_interrupt) {
-			pr_warn("ACPI: SPE must have homogeneous interrupts\n");
-			return -EINVAL;
-		}
-	}
-
-	irq = acpi_register_gsi(NULL, gsi, ACPI_LEVEL_SENSITIVE,
-				ACPI_ACTIVE_HIGH);
-	if (irq < 0) {
-		pr_warn("ACPI: SPE Unable to register interrupt: %d\n", gsi);
-		return irq;
-	}
-
-	/*
-	 * really we want SPE to behave like a normal ACPI device, with the
-	 * possibility of future power control methods, compatible flags/etc.
-	 * But we don't have that choice and acpi_add_single_object() and
-	 * acpi_create_platform_device() makes it hard to simulate that
-	 * functionality outside of DSDT.
-	 * Spinning this off as a platform device is the least evil
-	 * choice that gives us a normal driver module that can be
-	 * loaded/unloaded without a lot of overhead while keeping open the
-	 * possibility of future expansion via compatible alternative modules.
-	 */
-	spe_resources[0].start = irq;
-	ret = platform_device_register(&spe_dev);
-	if (ret < 0) {
-		pr_warn("ACPI: SPE: Unable to register device\n");
-		acpi_unregister_gsi(gsi);
-	}
-
-	return ret;
-}
-
 static int arm_pmu_acpi_parse_irqs(void)
 {
 	int irq, cpu, irq_cpu, err;
@@ -355,8 +279,6 @@ static int arm_pmu_acpi_init(void)
 	if (acpi_disabled)
 		return 0;
 
-	arm_spe_acpi_parse_irqs(); /* failures are expected */
-
 	ret = arm_pmu_acpi_parse_irqs();
 	if (ret)
 		return ret;