1 files changed, 153 insertions, 0 deletions
diff --git a/lib/sbi/sbi_ipi.c b/lib/sbi/sbi_ipi.c
new file mode 100644
index 0000000..48d5b22
--- /dev/null
+++ b/lib/sbi/sbi_ipi.c
@@ -0,0 +1,153 @@
+/*
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2019 Western Digital Corporation or its affiliates.
+ *
+ * Authors:
+ *   Anup Patel <anup.patel@wdc.com>
+ *   Nick Kossifidis <mick@ics.forth.gr>
+ */
+
+#include <sbi/riscv_asm.h>
+#include <sbi/riscv_barrier.h>
+#include <sbi/riscv_atomic.h>
+#include <sbi/riscv_unpriv.h>
+#include <sbi/sbi_error.h>
+#include <sbi/sbi_bitops.h>
+#include <sbi/sbi_hart.h>
+#include <sbi/sbi_ipi.h>
+#include <sbi/sbi_platform.h>
+#include <sbi/sbi_timer.h>
+#include <sbi/sbi_tlb.h>
+#include <plat/string.h>
+
+static unsigned long ipi_data_off;
+
+static int sbi_ipi_send(struct sbi_scratch *scratch, u32 hartid, u32 event,
+			void *data)
+{
+	int ret;
+	struct sbi_scratch *remote_scratch = NULL;
+	const struct sbi_platform *plat = sbi_platform_ptr(scratch);
+	struct sbi_ipi_data *ipi_data;
+
+	if (sbi_platform_hart_disabled(plat, hartid))
+		return -1;
+
+	/*
+	 * Set IPI type on remote hart's scratch area and
+	 * trigger the interrupt
+	 */
+	remote_scratch = sbi_hart_id_to_scratch(scratch, hartid);
+	ipi_data = sbi_scratch_offset_ptr(remote_scratch, ipi_data_off);
+	if (event == SBI_IPI_EVENT_SFENCE_VMA ||
+	    event == SBI_IPI_EVENT_SFENCE_VMA_ASID) {
+		ret = sbi_tlb_fifo_update(remote_scratch, event, data);
+		if (ret > 0)
+			goto done;
+		else if (ret < 0)
+			return ret;
+	}
+	atomic_raw_set_bit(event, &ipi_data->ipi_type);
+	mb();
+	sbi_platform_ipi_send(plat, hartid);
+	if (event != SBI_IPI_EVENT_SOFT)
+		sbi_platform_ipi_sync(plat, hartid);
+
+done:
+	return 0;
+}
+
+int sbi_ipi_send_many(struct sbi_scratch *scratch, struct unpriv_trap *uptrap,
+		      ulong *pmask, u32 event, void *data)
+{
+	ulong i, m;
+	ulong mask = sbi_hart_available_mask();
+	u32 hartid = sbi_current_hartid();
+
+	if (pmask) {
+		mask &= load_ulong(pmask, scratch, uptrap);
+		if (uptrap->cause)
+			return SBI_ETRAP;
+	}
+
+	/* send IPIs to every other hart on the set */
+	for (i = 0, m = mask; m; i++, m >>= 1)
+		if ((m & 1UL) && (i != hartid))
+			sbi_ipi_send(scratch, i, event, data);
+
+	/* If the current hart is on the set, send an IPI
+	 * to it as well
+	 */
+	if (mask & (1UL << hartid))
+		sbi_ipi_send(scratch, hartid, event, data);
+
+	return 0;
+}
+
+void sbi_ipi_clear_smode(struct sbi_scratch *scratch)
+{
+	csr_clear(CSR_MIP, MIP_SSIP);
+}
+
+void sbi_ipi_process(struct sbi_scratch *scratch)
+{
+	volatile unsigned long ipi_type;
+	unsigned int ipi_event;
+	const struct sbi_platform *plat = sbi_platform_ptr(scratch);
+	struct sbi_ipi_data *ipi_data =
+			sbi_scratch_offset_ptr(scratch, ipi_data_off);
+
+	u32 hartid = sbi_current_hartid();
+	sbi_platform_ipi_clear(plat, hartid);
+
+	do {
+		ipi_type = ipi_data->ipi_type;
+		rmb();
+		ipi_event = __ffs(ipi_type);
+		switch (ipi_event) {
+		case SBI_IPI_EVENT_SOFT:
+			csr_set(CSR_MIP, MIP_SSIP);
+			break;
+		case SBI_IPI_EVENT_FENCE_I:
+			__asm__ __volatile("fence.i");
+			break;
+		case SBI_IPI_EVENT_SFENCE_VMA:
+		case SBI_IPI_EVENT_SFENCE_VMA_ASID:
+			sbi_tlb_fifo_process(scratch, ipi_event);
+			break;
+		case SBI_IPI_EVENT_HALT:
+			sbi_hart_hang();
+			break;
+		};
+		ipi_type = atomic_raw_clear_bit(ipi_event, &ipi_data->ipi_type);
+	} while (ipi_type > 0);
+}
+
+int sbi_ipi_init(struct sbi_scratch *scratch, bool cold_boot)
+{
+	int ret;
+	struct sbi_ipi_data *ipi_data;
+
+	if (cold_boot) {
+		ipi_data_off = sbi_scratch_alloc_offset(sizeof(*ipi_data),
+							"IPI_DATA");
+		if (!ipi_data_off)
+			return SBI_ENOMEM;
+	} else {
+		if (!ipi_data_off)
+			return SBI_ENOMEM;
+	}
+
+	ipi_data = sbi_scratch_offset_ptr(scratch, ipi_data_off);
+	ipi_data->ipi_type = 0x00;
+
+	ret = sbi_tlb_fifo_init(scratch, cold_boot);
+	if (ret)
+		return ret;
+
+	/* Enable software interrupts */
+	csr_set(CSR_MIE, MIP_MSIP);
+
+	return sbi_platform_ipi_init(sbi_platform_ptr(scratch), cold_boot);
+}