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path: root/drivers/irqchip/irq-gic-v3-its.c
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Diffstat (limited to 'drivers/irqchip/irq-gic-v3-its.c')
-rw-r--r--drivers/irqchip/irq-gic-v3-its.c267
1 files changed, 215 insertions, 52 deletions
diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index 2cbb19cddbf8..2982e93d2369 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;
@@ -1875,16 +1879,6 @@ static void its_cpu_init_lpis(void)
gic_data_rdist()->pend_page = pend_page;
}
- /* Disable LPIs */
- val = readl_relaxed(rbase + GICR_CTLR);
- val &= ~GICR_CTLR_ENABLE_LPIS;
- writel_relaxed(val, rbase + GICR_CTLR);
-
- /*
- * Make sure any change to the table is observable by the GIC.
- */
- dsb(sy);
-
/* set PROPBASE */
val = (page_to_phys(gic_rdists->prop_page) |
GICR_PROPBASER_InnerShareable |
@@ -1938,52 +1932,53 @@ static void its_cpu_init_lpis(void)
dsb(sy);
}
-static void its_cpu_init_collection(void)
+static void its_cpu_init_collection(struct its_node *its)
{
- struct its_node *its;
- int cpu;
-
- spin_lock(&its_lock);
- cpu = smp_processor_id();
-
- list_for_each_entry(its, &its_nodes, entry) {
- u64 target;
+ int cpu = smp_processor_id();
+ u64 target;
- /* avoid cross node collections and its mapping */
- if (its->flags & ITS_FLAGS_WORKAROUND_CAVIUM_23144) {
- struct device_node *cpu_node;
+ /* avoid cross node collections and its mapping */
+ if (its->flags & ITS_FLAGS_WORKAROUND_CAVIUM_23144) {
+ struct device_node *cpu_node;
- cpu_node = of_get_cpu_node(cpu, NULL);
- if (its->numa_node != NUMA_NO_NODE &&
- its->numa_node != of_node_to_nid(cpu_node))
- continue;
- }
+ cpu_node = of_get_cpu_node(cpu, NULL);
+ if (its->numa_node != NUMA_NO_NODE &&
+ its->numa_node != of_node_to_nid(cpu_node))
+ return;
+ }
+ /*
+ * We now have to bind each collection to its target
+ * redistributor.
+ */
+ if (gic_read_typer(its->base + GITS_TYPER) & GITS_TYPER_PTA) {
/*
- * We now have to bind each collection to its target
+ * This ITS wants the physical address of the
* redistributor.
*/
- if (gic_read_typer(its->base + GITS_TYPER) & GITS_TYPER_PTA) {
- /*
- * This ITS wants the physical address of the
- * redistributor.
- */
- target = gic_data_rdist()->phys_base;
- } else {
- /*
- * This ITS wants a linear CPU number.
- */
- target = gic_read_typer(gic_data_rdist_rd_base() + GICR_TYPER);
- target = GICR_TYPER_CPU_NUMBER(target) << 16;
- }
+ target = gic_data_rdist()->phys_base;
+ } else {
+ /* This ITS wants a linear CPU number. */
+ target = gic_read_typer(gic_data_rdist_rd_base() + GICR_TYPER);
+ target = GICR_TYPER_CPU_NUMBER(target) << 16;
+ }
- /* Perform collection mapping */
- its->collections[cpu].target_address = target;
- its->collections[cpu].col_id = cpu;
+ /* Perform collection mapping */
+ its->collections[cpu].target_address = target;
+ its->collections[cpu].col_id = cpu;
- its_send_mapc(its, &its->collections[cpu], 1);
- its_send_invall(its, &its->collections[cpu]);
- }
+ its_send_mapc(its, &its->collections[cpu], 1);
+ its_send_invall(its, &its->collections[cpu]);
+}
+
+static void its_cpu_init_collections(void)
+{
+ struct its_node *its;
+
+ spin_lock(&its_lock);
+
+ list_for_each_entry(its, &its_nodes, entry)
+ its_cpu_init_collection(its);
spin_unlock(&its_lock);
}
@@ -3041,6 +3036,113 @@ 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);
+
+ /*
+ * Reinit the collection if it's stored in the ITS. This is
+ * indicated by the col_id being less than the HCC field.
+ * CID < HCC as specified in the GIC v3 Documentation.
+ */
+ if (its->collections[smp_processor_id()].col_id <
+ GITS_TYPER_HCC(gic_read_typer(base + GITS_TYPER)))
+ its_cpu_init_collection(its);
+ }
+ 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;
@@ -3260,6 +3362,9 @@ 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;
@@ -3287,15 +3392,71 @@ static bool gic_rdists_supports_plpis(void)
return !!(gic_read_typer(gic_data_rdist_rd_base() + GICR_TYPER) & GICR_TYPER_PLPIS);
}
+static int redist_disable_lpis(void)
+{
+ void __iomem *rbase = gic_data_rdist_rd_base();
+ u64 timeout = USEC_PER_SEC;
+ u64 val;
+
+ if (!gic_rdists_supports_plpis()) {
+ pr_info("CPU%d: LPIs not supported\n", smp_processor_id());
+ return -ENXIO;
+ }
+
+ val = readl_relaxed(rbase + GICR_CTLR);
+ if (!(val & GICR_CTLR_ENABLE_LPIS))
+ return 0;
+
+ pr_warn("CPU%d: Booted with LPIs enabled, memory probably corrupted\n",
+ smp_processor_id());
+ add_taint(TAINT_CRAP, LOCKDEP_STILL_OK);
+
+ /* Disable LPIs */
+ val &= ~GICR_CTLR_ENABLE_LPIS;
+ writel_relaxed(val, rbase + GICR_CTLR);
+
+ /* Make sure any change to GICR_CTLR is observable by the GIC */
+ dsb(sy);
+
+ /*
+ * Software must observe RWP==0 after clearing GICR_CTLR.EnableLPIs
+ * from 1 to 0 before programming GICR_PEND{PROP}BASER registers.
+ * Error out if we time out waiting for RWP to clear.
+ */
+ while (readl_relaxed(rbase + GICR_CTLR) & GICR_CTLR_RWP) {
+ if (!timeout) {
+ pr_err("CPU%d: Timeout while disabling LPIs\n",
+ smp_processor_id());
+ return -ETIMEDOUT;
+ }
+ udelay(1);
+ timeout--;
+ }
+
+ /*
+ * After it has been written to 1, it is IMPLEMENTATION
+ * DEFINED whether GICR_CTLR.EnableLPI becomes RES1 or can be
+ * cleared to 0. Error out if clearing the bit failed.
+ */
+ if (readl_relaxed(rbase + GICR_CTLR) & GICR_CTLR_ENABLE_LPIS) {
+ pr_err("CPU%d: Failed to disable LPIs\n", smp_processor_id());
+ return -EBUSY;
+ }
+
+ return 0;
+}
+
int its_cpu_init(void)
{
if (!list_empty(&its_nodes)) {
- if (!gic_rdists_supports_plpis()) {
- pr_info("CPU%d: LPIs not supported\n", smp_processor_id());
- return -ENXIO;
- }
+ int ret;
+
+ ret = redist_disable_lpis();
+ if (ret)
+ return ret;
+
its_cpu_init_lpis();
- its_cpu_init_collection();
+ its_cpu_init_collections();
}
return 0;
@@ -3516,5 +3677,7 @@ int __init its_init(struct fwnode_handle *handle, struct rdists *rdists,
}
}
+ register_syscore_ops(&its_syscore_ops);
+
return 0;
}