1 files changed, 137 insertions, 0 deletions
diff --git a/lib/utils/ipi/andes_plicsw.c b/lib/utils/ipi/andes_plicsw.c
new file mode 100644
index 0000000..db25ae2
--- /dev/null
+++ b/lib/utils/ipi/andes_plicsw.c
@@ -0,0 +1,137 @@
+/*
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2022 Andes Technology Corporation
+ *
+ * Authors:
+ *   Zong Li <zong@andestech.com>
+ *   Nylon Chen <nylon7@andestech.com>
+ *   Leo Yu-Chi Liang <ycliang@andestech.com>
+ *   Yu Chien Peter Lin <peterlin@andestech.com>
+ */
+
+#include <sbi/riscv_asm.h>
+#include <sbi/riscv_io.h>
+#include <sbi/sbi_domain.h>
+#include <sbi/sbi_ipi.h>
+#include <sbi_utils/ipi/andes_plicsw.h>
+
+struct plicsw_data plicsw;
+
+static inline void plicsw_claim(void)
+{
+	u32 hartid = current_hartid();
+
+	if (plicsw.hart_count <= hartid)
+		ebreak();
+
+	plicsw.source_id[hartid] =
+		readl((void *)plicsw.addr + PLICSW_CONTEXT_BASE +
+		      PLICSW_CONTEXT_CLAIM + PLICSW_CONTEXT_STRIDE * hartid);
+}
+
+static inline void plicsw_complete(void)
+{
+	u32 hartid = current_hartid();
+	u32 source = plicsw.source_id[hartid];
+
+	writel(source, (void *)plicsw.addr + PLICSW_CONTEXT_BASE +
+			       PLICSW_CONTEXT_CLAIM +
+			       PLICSW_CONTEXT_STRIDE * hartid);
+}
+
+static inline void plic_sw_pending(u32 target_hart)
+{
+	/*
+	 * The pending array registers are w1s type.
+	 * IPI pending array mapping as following:
+	 *
+	 * Pending array start address: base + 0x1000
+	 * ---------------------------------
+	 * | hart3 | hart2 | hart1 | hart0 |
+	 * ---------------------------------
+	 * Each hartX can send IPI to another hart by setting the
+	 * bitY to its own region (see the below).
+	 *
+	 * In each hartX region:
+	 * <---------- PICSW_PENDING_STRIDE -------->
+	 * | bit7 | ... | bit3 | bit2 | bit1 | bit0 |
+	 * ------------------------------------------
+	 * The bitY of hartX region indicates that hartX sends an
+	 * IPI to hartY.
+	 */
+	u32 hartid	    = current_hartid();
+	u32 word_index	    = hartid / 4;
+	u32 per_hart_offset = PLICSW_PENDING_STRIDE * hartid;
+	u32 val		    = 1 << target_hart << per_hart_offset;
+
+	writel(val, (void *)plicsw.addr + PLICSW_PENDING_BASE + word_index * 4);
+}
+
+static void plicsw_ipi_send(u32 target_hart)
+{
+	if (plicsw.hart_count <= target_hart)
+		ebreak();
+
+	/* Set PLICSW IPI */
+	plic_sw_pending(target_hart);
+}
+
+static void plicsw_ipi_clear(u32 target_hart)
+{
+	if (plicsw.hart_count <= target_hart)
+		ebreak();
+
+	/* Clear PLICSW IPI */
+	plicsw_claim();
+	plicsw_complete();
+}
+
+static struct sbi_ipi_device plicsw_ipi = {
+	.name      = "andes_plicsw",
+	.ipi_send  = plicsw_ipi_send,
+	.ipi_clear = plicsw_ipi_clear
+};
+
+int plicsw_warm_ipi_init(void)
+{
+	u32 hartid = current_hartid();
+
+	/* Clear PLICSW IPI */
+	plicsw_ipi_clear(hartid);
+
+	return 0;
+}
+
+int plicsw_cold_ipi_init(struct plicsw_data *plicsw)
+{
+	int rc;
+
+	/* Setup source priority */
+	uint32_t *priority = (void *)plicsw->addr + PLICSW_PRIORITY_BASE;
+
+	for (int i = 0; i < plicsw->hart_count; i++)
+		writel(1, &priority[i]);
+
+	/* Setup target enable */
+	uint32_t enable_mask = PLICSW_HART_MASK;
+
+	for (int i = 0; i < plicsw->hart_count; i++) {
+		uint32_t *enable = (void *)plicsw->addr + PLICSW_ENABLE_BASE +
+				   PLICSW_ENABLE_STRIDE * i;
+		writel(enable_mask, enable);
+		writel(enable_mask, enable + 1);
+		enable_mask <<= 1;
+	}
+
+	/* Add PLICSW region to the root domain */
+	rc = sbi_domain_root_add_memrange(plicsw->addr, plicsw->size,
+					  PLICSW_REGION_ALIGN,
+					  SBI_DOMAIN_MEMREGION_MMIO);
+	if (rc)
+		return rc;
+
+	sbi_ipi_set_device(&plicsw_ipi);
+
+	return 0;
+}