tools/litex_json2dts_linux: add *-endian to support csr ordering

csr_ordering default is "big" but there was no way for software
to detect if csr_ordering was changed to "little" to match the cpu.

litex/tools/litex_json2dts_linux.py

@@ -54,6 +54,11 @@ def generate_dts(d, initrd_start=None, initrd_size=None, initrd=None, root_devic
 
  cpu_mmu = d["constants"].get("config_cpu_mmu", None)
 
+ # CSR Parameters -------------------------------------------------------------------------------
+ csr_ordering = d["constants"].get("config_csr_ordering", "big")
+ assert csr_ordering in ["big", "little"]
+ dts_endian = f"{csr_ordering}-endian;"
+
  # Header ---------------------------------------------------------------------------------------
  dts = """
 /dts-v1/;
@@ -517,6 +522,7 @@ def generate_dts(d, initrd_start=None, initrd_size=None, initrd=None, root_devic
  vmmc-supply = <&vreg_mmc>;
  bus-width = <0x04>;
  {sdcard_irq_interrupt}
+ {dts_endian}
  status = "okay";
  }};
 """.format(
@@ -526,6 +532,7 @@ def generate_dts(d, initrd_start=None, initrd_size=None, initrd=None, root_devic
  sdcard_block2mem = d["csr_bases"]["sdcard_block2mem"],
  sdcard_mem2block = d["csr_bases"]["sdcard_mem2block"],
  sdcard_irq = d["csr_bases"]["sdcard_irq"],
+ dts_endian = dts_endian,
  sdcard_irq_interrupt = "" if polling else "interrupts = <{}>;".format(d["constants"]["sdcard_irq_interrupt"])
 )
  # Leds -----------------------------------------------------------------------------------------