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-rw-r--r--drivers/irqchip/irq-gic-v3-its.c107
-rw-r--r--include/linux/irqchip/arm-gic-v3.h3
2 files changed, 109 insertions, 1 deletions
diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index 1d3056f53747..06682c33acba 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -33,6 +33,7 @@
#include <linux/of_platform.h>
#include <linux/percpu.h>
#include <linux/slab.h>
+#include <linux/syscore_ops.h>
#include <linux/irqchip.h>
#include <linux/irqchip/arm-gic-v3.h>
@@ -46,6 +47,7 @@
#define ITS_FLAGS_CMDQ_NEEDS_FLUSHING (1ULL << 0)
#define ITS_FLAGS_WORKAROUND_CAVIUM_22375 (1ULL << 1)
#define ITS_FLAGS_WORKAROUND_CAVIUM_23144 (1ULL << 2)
+#define ITS_FLAGS_SAVE_SUSPEND_STATE (1ULL << 3)
#define RDIST_FLAGS_PROPBASE_NEEDS_FLUSHING (1 << 0)
@@ -101,6 +103,8 @@ struct its_node {
struct its_collection *collections;
struct fwnode_handle *fwnode_handle;
u64 (*get_msi_base)(struct its_device *its_dev);
+ u64 cbaser_save;
+ u32 ctlr_save;
struct list_head its_device_list;
u64 flags;
unsigned long list_nr;
@@ -3042,6 +3046,104 @@ static void its_enable_quirks(struct its_node *its)
gic_enable_quirks(iidr, its_quirks, its);
}
+static int its_save_disable(void)
+{
+ struct its_node *its;
+ int err = 0;
+
+ spin_lock(&its_lock);
+ list_for_each_entry(its, &its_nodes, entry) {
+ void __iomem *base;
+
+ if (!(its->flags & ITS_FLAGS_SAVE_SUSPEND_STATE))
+ continue;
+
+ base = its->base;
+ its->ctlr_save = readl_relaxed(base + GITS_CTLR);
+ err = its_force_quiescent(base);
+ if (err) {
+ pr_err("ITS@%pa: failed to quiesce: %d\n",
+ &its->phys_base, err);
+ writel_relaxed(its->ctlr_save, base + GITS_CTLR);
+ goto err;
+ }
+
+ its->cbaser_save = gits_read_cbaser(base + GITS_CBASER);
+ }
+
+err:
+ if (err) {
+ list_for_each_entry_continue_reverse(its, &its_nodes, entry) {
+ void __iomem *base;
+
+ if (!(its->flags & ITS_FLAGS_SAVE_SUSPEND_STATE))
+ continue;
+
+ base = its->base;
+ writel_relaxed(its->ctlr_save, base + GITS_CTLR);
+ }
+ }
+ spin_unlock(&its_lock);
+
+ return err;
+}
+
+static void its_restore_enable(void)
+{
+ struct its_node *its;
+ int ret;
+
+ spin_lock(&its_lock);
+ list_for_each_entry(its, &its_nodes, entry) {
+ void __iomem *base;
+ int i;
+
+ if (!(its->flags & ITS_FLAGS_SAVE_SUSPEND_STATE))
+ continue;
+
+ base = its->base;
+
+ /*
+ * Make sure that the ITS is disabled. If it fails to quiesce,
+ * don't restore it since writing to CBASER or BASER<n>
+ * registers is undefined according to the GIC v3 ITS
+ * Specification.
+ */
+ ret = its_force_quiescent(base);
+ if (ret) {
+ pr_err("ITS@%pa: failed to quiesce on resume: %d\n",
+ &its->phys_base, ret);
+ continue;
+ }
+
+ gits_write_cbaser(its->cbaser_save, base + GITS_CBASER);
+
+ /*
+ * Writing CBASER resets CREADR to 0, so make CWRITER and
+ * cmd_write line up with it.
+ */
+ its->cmd_write = its->cmd_base;
+ gits_write_cwriter(0, base + GITS_CWRITER);
+
+ /* Restore GITS_BASER from the value cache. */
+ for (i = 0; i < GITS_BASER_NR_REGS; i++) {
+ struct its_baser *baser = &its->tables[i];
+
+ if (!(baser->val & GITS_BASER_VALID))
+ continue;
+
+ its_write_baser(its, baser, baser->val);
+ }
+ writel_relaxed(its->ctlr_save, base + GITS_CTLR);
+ }
+ spin_unlock(&its_lock);
+}
+
+static struct syscore_ops its_syscore_ops = {
+ .suspend = its_save_disable,
+ .resume = its_restore_enable,
+};
+
static int its_init_domain(struct fwnode_handle *handle, struct its_node *its)
{
struct irq_domain *inner_domain;
@@ -3261,6 +3363,9 @@ static int __init its_probe_one(struct resource *res,
ctlr |= GITS_CTLR_ImDe;
writel_relaxed(ctlr, its->base + GITS_CTLR);
+ if (GITS_TYPER_HCC(typer))
+ its->flags |= ITS_FLAGS_SAVE_SUSPEND_STATE;
+
err = its_init_domain(handle, its);
if (err)
goto out_free_tables;
@@ -3517,5 +3622,7 @@ int __init its_init(struct fwnode_handle *handle, struct rdists *rdists,
}
}
+ register_syscore_ops(&its_syscore_ops);
+
return 0;
}
diff --git a/include/linux/irqchip/arm-gic-v3.h b/include/linux/irqchip/arm-gic-v3.h
index c00c4c33e432..9aacea2aa938 100644
--- a/include/linux/irqchip/arm-gic-v3.h
+++ b/include/linux/irqchip/arm-gic-v3.h
@@ -312,7 +312,8 @@
#define GITS_TYPER_DEVBITS_SHIFT 13
#define GITS_TYPER_DEVBITS(r) ((((r) >> GITS_TYPER_DEVBITS_SHIFT) & 0x1f) + 1)
#define GITS_TYPER_PTA (1UL << 19)
-#define GITS_TYPER_HWCOLLCNT_SHIFT 24
+#define GITS_TYPER_HCC_SHIFT 24
+#define GITS_TYPER_HCC(r) (((r) >> GITS_TYPER_HCC_SHIFT) & 0xff)
#define GITS_TYPER_VMOVP (1ULL << 37)
#define GITS_IIDR_REV_SHIFT 12