[PATCH v2 10/13] lib: utils: Disable appropriate IMSIC DT nodes in fdt_fixups()

[Anup Patel]

We should disable IMSIC DT nodes in fdt_fixups() which are not
accessible to the next booting stage based on currently assigned
domain.

Signed-off-by: Anup Patel <anup.patel at wdc.com>
Signed-off-by: Anup Patel <apatel at ventanamicro.com>
Reviewed-by: Atish Patra <atishp at rivosinc.com>
---
 include/sbi_utils/fdt/fdt_fixup.h | 17 ++++++++++++++--
 lib/utils/fdt/fdt_fixup.c         | 32 +++++++++++++++++++++++++++++--
 2 files changed, 45 insertions(+), 4 deletions(-)

diff --git a/include/sbi_utils/fdt/fdt_fixup.h b/include/sbi_utils/fdt/fdt_fixup.h
index c38e5d9..77575bb 100644
--- a/include/sbi_utils/fdt/fdt_fixup.h
+++ b/include/sbi_utils/fdt/fdt_fixup.h
@@ -21,6 +21,18 @@
  */
 void fdt_cpu_fixup(void *fdt);
 
+/**
+ * Fix up the IMSIC nodes in the device tree
+ *
+ * This routine disables IMSIC nodes which are not accessible to the next
+ * booting stage based on currently assigned domain.
+ *
+ * It is recommended that platform codes call this helper in their final_init()
+ *
+ * @param fdt: device tree blob
+ */
+void fdt_imsic_fixup(void *fdt);
+
 /**
  * Fix up the PLIC node in the device tree
  *
@@ -64,8 +76,9 @@ int fdt_reserved_memory_nomap_fixup(void *fdt);
  * General device tree fix-up
  *
  * This routine do all required device tree fix-ups for a typical platform.
- * It fixes up the PLIC node and the reserved memory node in the device tree
- * by calling the corresponding helper routines to accomplish the task.
+ * It fixes up the PLIC node, IMSIC nodes, and the reserved memory node in
+ * the device tree by calling the corresponding helper routines to accomplish
+ * the task.
  *
  * It is recommended that platform codes call this helper in their final_init()
  *
diff --git a/lib/utils/fdt/fdt_fixup.c b/lib/utils/fdt/fdt_fixup.c
index ac01ba3..c2460b8 100644
--- a/lib/utils/fdt/fdt_fixup.c
+++ b/lib/utils/fdt/fdt_fixup.c
@@ -52,6 +52,34 @@ void fdt_cpu_fixup(void *fdt)
 	}
 }
 
+static void fdt_domain_based_fixup_one(void *fdt, int nodeoff)
+{
+	int rc;
+	uint64_t reg_addr, reg_size;
+	struct sbi_domain *dom = sbi_domain_thishart_ptr();
+
+	rc = fdt_get_node_addr_size(fdt, nodeoff, 0, &reg_addr, &reg_size);
+	if (rc < 0 || !reg_addr || !reg_size)
+		return;
+
+	if (!sbi_domain_check_addr(dom, reg_addr, dom->next_mode,
+				    SBI_DOMAIN_READ | SBI_DOMAIN_WRITE)) {
+		rc = fdt_open_into(fdt, fdt, fdt_totalsize(fdt) + 32);
+		if (rc < 0)
+			return;
+		fdt_setprop_string(fdt, nodeoff, "status", "disabled");
+	}
+}
+
+void fdt_imsic_fixup(void *fdt)
+{
+	int noff = 0;
+
+	while ((noff = fdt_node_offset_by_compatible(fdt, noff,
+						     "riscv,imsics")) >= 0)
+		fdt_domain_based_fixup_one(fdt, noff);
+}
+
 void fdt_plic_fixup(void *fdt)
 {
 	u32 *cells;
@@ -261,10 +289,10 @@ int fdt_reserved_memory_nomap_fixup(void *fdt)
 
 void fdt_fixups(void *fdt)
 {
+	fdt_imsic_fixup(fdt);
+
 	fdt_plic_fixup(fdt);
 
 	fdt_reserved_memory_fixup(fdt);
 	fdt_pmu_fixup(fdt);
 }
-
-
-- 
2.25.1