Documentation/devicetree/bindings/soc/qcom/qcom,smem.txt

   1 Qualcomm Shared Memory Manager binding
   2
   3 This binding describes the Qualcomm Shared Memory Manager, used to share data
   4 between various subsystems and OSes in Qualcomm platforms.
   5
   6 - compatible:
   7         Usage: required
   8         Value type: <stringlist>
   9         Definition: must be:
  10                     "qcom,smem"
  11
  12 - memory-region:
  13         Usage: required
  14         Value type: <prop-encoded-array>
  15         Definition: handle to memory reservation for main SMEM memory region.
  16
  17 - qcom,rpm-msg-ram:
  18         Usage: required
  19         Value type: <prop-encoded-array>
  20         Definition: handle to RPM message memory resource
  21
  22 - hwlocks:
  23         Usage: required
  24         Value type: <prop-encoded-array>
  25         Definition: reference to a hwspinlock used to protect allocations from
  26                     the shared memory
  27
  28 = EXAMPLE
  29 The following example shows the SMEM setup for MSM8974, with a main SMEM region
  30 at 0xfa00000 and the RPM message ram at 0xfc428000:
  31
  32         reserved-memory {
  33                 #address-cells = <1>;
  34                 #size-cells = <1>;
  35                 ranges;
  36
  37                 smem_region: smem@fa00000 {
  38                         reg = <0xfa00000 0x200000>;
  39                         no-map;
  40                 };
  41         };
  42
  43         smem@fa00000 {
  44                 compatible = "qcom,smem";
  45
  46                 memory-region = <&smem_region>;
  47                 qcom,rpm-msg-ram = <&rpm_msg_ram>;
  48
  49                 hwlocks = <&tcsr_mutex 3>;
  50         };
  51
  52         soc {
  53                 rpm_msg_ram: memory@fc428000 {
  54                         compatible = "qcom,rpm-msg-ram";
  55                         reg = <0xfc428000 0x4000>;
  56                 };
  57         };