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Diffstat (limited to 'drivers/arm/gic/v3/arm_gicv3_common.c')
-rw-r--r--drivers/arm/gic/v3/arm_gicv3_common.c115
1 files changed, 115 insertions, 0 deletions
diff --git a/drivers/arm/gic/v3/arm_gicv3_common.c b/drivers/arm/gic/v3/arm_gicv3_common.c
new file mode 100644
index 0000000..4489892
--- /dev/null
+++ b/drivers/arm/gic/v3/arm_gicv3_common.c
@@ -0,0 +1,115 @@
+/*
+ * Copyright (c) 2017, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+/*
+ * Driver for implementation defined features that are identical in ARM GICv3
+* implementations (GIC-500 and GIC-600 for now). This driver only overrides
+* APIs that are different to those generic ones in GICv3 driver.
+ */
+
+#include <assert.h>
+
+#include <arch_helpers.h>
+#include <drivers/arm/arm_gicv3_common.h>
+#include <drivers/arm/gicv3.h>
+
+#include "gicv3_private.h"
+
+/*
+ * Flush the internal GIC cache of the LPIs pending tables to memory before
+ * saving the state of the Redistributor. This is required before powering off
+ * the GIC when the pending status must be preserved.
+ * `rdist_proc_num` is the processor number corresponding to the Redistributor of the
+ * current CPU.
+ */
+void arm_gicv3_distif_pre_save(unsigned int rdist_proc_num)
+{
+ uintptr_t gicr_base = 0;
+
+ assert(gicv3_driver_data);
+ assert(gicv3_driver_data->rdistif_base_addrs);
+
+ /*
+ * The GICR_WAKER.Sleep bit should be set only when both
+ * GICR_WAKER.ChildrenAsleep and GICR_WAKER.ProcessorSleep are set on
+ * all the Redistributors.
+ */
+ for (unsigned int i = 0; i < gicv3_driver_data->rdistif_num; i++) {
+ gicr_base = gicv3_driver_data->rdistif_base_addrs[i];
+ assert(gicr_base);
+ assert(gicr_read_waker(gicr_base) & WAKER_CA_BIT);
+ assert(gicr_read_waker(gicr_base) & WAKER_PS_BIT);
+ }
+
+ gicr_base = gicv3_driver_data->rdistif_base_addrs[rdist_proc_num];
+ /*
+ * According to the TRM, there is only one instance of the
+ * GICR_WAKER.Sleep and GICR_WAKER.Quiescent bits that can be accessed
+ * through any of the Redistributor.
+ */
+
+ /*
+ * Set GICR_WAKER.Sleep
+ * After this point, the system must be configured so that the
+ * wake_request signals for the right cores are asserted when a wakeup
+ * interrupt is detected. The GIC will not be able to do that anymore
+ * when the GICR_WAKER.Sleep bit is set to 1.
+ */
+ gicr_write_waker(gicr_base, gicr_read_waker(gicr_base) | WAKER_SL_BIT);
+
+ /* Wait until the GICR_WAKER.Quiescent bit is set */
+ while (!(gicr_read_waker(gicr_base) & WAKER_QSC_BIT))
+ ;
+}
+
+/*
+ * Allow the LPIs pending state to be read back from the tables in memory after
+ * having restored the state of the GIC Redistributor.
+ */
+void arm_gicv3_distif_post_restore(unsigned int rdist_proc_num)
+{
+ uintptr_t gicr_base;
+
+ assert(gicv3_driver_data);
+ assert(gicv3_driver_data->rdistif_base_addrs);
+
+ /*
+ * According to the TRM, there is only one instance of the
+ * GICR_WAKER.Sleep and GICR_WAKER.Quiescent bits that can be accessed
+ * through any of the Redistributor.
+ */
+ gicr_base = gicv3_driver_data->rdistif_base_addrs[rdist_proc_num];
+ assert(gicr_base);
+
+ /*
+ * If the GIC had power removed, the GICR_WAKER state will be reset.
+ * Since the GICR_WAKER.Sleep and GICR_WAKER.Quiescent bits are cleared,
+ * we can exit early. This also prevents the following assert from
+ * erroneously triggering.
+ */
+ if (!(gicr_read_waker(gicr_base) & WAKER_SL_BIT))
+ return;
+
+ /*
+ * Writes to GICR_WAKER.Sleep bit are ignored if GICR_WAKER.Quiescent
+ * bit is not set. We should be alright on power on path, therefore
+ * coming out of sleep and Quiescent should be set, but we assert in
+ * case.
+ */
+ assert(gicr_read_waker(gicr_base) & WAKER_QSC_BIT);
+
+ /* Clear GICR_WAKER.Sleep */
+ gicr_write_waker(gicr_base, gicr_read_waker(gicr_base) & ~WAKER_SL_BIT);
+
+ /*
+ * We don't know if the effects of setting GICR_WAKER.Sleep bit is
+ * instantaneous, so we wait until the interface is not Quiescent
+ * anymore.
+ */
+ while (gicr_read_waker(gicr_base) & WAKER_QSC_BIT)
+ ;
+}
+