[PATCH] arm64: dts: rockchip: Add cache information to the SoC dtsi for RK3399

[Dragan Simic <dsimic@manjaro.org>]

Add missing cache information to the Rockchip RK3399 SoC dtsi.  The specified
values were derived by hand from the cache size specifications available from
the RK3399 datasheet;  for future reference, here's a brief summary:

  - Each Cortex-A72 core has 48 KB of L1 instruction cache and
    32 KB of L1 data cache available, four-way set associative
  - Each Cortex-A53 core core has 32 KB of instruction cache and
    32 KB of L1 data cache available, four-way set associative
  - The big (A72) cluster has 1 MB of unified L2 cache available
  - The little (A53) cluster has 512 KB of unified L2 cache available

This patch allows /proc/cpuinfo and lscpu(1) to display proper RK3399 cache
information, and it eliminates the following error in the kernel log:

  cacheinfo: Unable to detect cache hierarchy for CPU 0

While there, add a couple of somewhat useful comments, which may help a bit
anyone going through the RK3399 SoC dtsi.

Co-developed-by: Kyle Copperfield <kmcopper@danwin1210.me>
Signed-off-by: Dragan Simic <dsimic@manjaro.org>
---

Notes:
    It's been a while since Kyle and I worked on this patch, and his email
    address seems to no longer work.  Unfortunately, I have no idea is there
    some other email address that he actually uses now.  However, Kyle needs
    to be mentioned as a co-author of this patch.

 arch/arm64/boot/dts/rockchip/rk3399.dtsi | 64 +++++++++++++++++++++++-
 1 file changed, 62 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/boot/dts/rockchip/rk3399.dtsi b/arch/arm64/boot/dts/rockchip/rk3399.dtsi
index da0dfb237f85..f38c27f87cc9 100644
--- a/arch/arm64/boot/dts/rockchip/rk3399.dtsi
+++ b/arch/arm64/boot/dts/rockchip/rk3399.dtsi
@@ -41,22 +41,22 @@ cpus {
 		#size-cells = <0>;
 
 		cpu-map {
-			cluster0 {
+			cluster0 {	/* Cortex-A53 */
 				core0 {
 					cpu = <&cpu_l0>;
 				};
 				core1 {
 					cpu = <&cpu_l1>;
 				};
 				core2 {
 					cpu = <&cpu_l2>;
 				};
 				core3 {
 					cpu = <&cpu_l3>;
 				};
 			};
 
-			cluster1 {
+			cluster1 {	/* Cortex-A72 */
 				core0 {
 					cpu = <&cpu_b0>;
 				};
@@ -76,54 +76,89 @@ cpu_l0: cpu@0 {
 			#cooling-cells = <2>; /* min followed by max */
 			dynamic-power-coefficient = <100>;
 			cpu-idle-states = <&CPU_SLEEP &CLUSTER_SLEEP>;
+			i-cache-size = <0x8000>;
+			i-cache-line-size = <64>;
+			i-cache-sets = <256>;
+			d-cache-size = <0x8000>;
+			d-cache-line-size = <64>;
+			d-cache-sets = <128>;
+			next-level-cache = <&l2_cache_l>;
 		};
 
 		cpu_l1: cpu@1 {
 			device_type = "cpu";
 			compatible = "arm,cortex-a53";
 			reg = <0x0 0x1>;
 			enable-method = "psci";
 			capacity-dmips-mhz = <485>;
 			clocks = <&cru ARMCLKL>;
 			#cooling-cells = <2>; /* min followed by max */
 			dynamic-power-coefficient = <100>;
 			cpu-idle-states = <&CPU_SLEEP &CLUSTER_SLEEP>;
+			i-cache-size = <0x8000>;
+			i-cache-line-size = <64>;
+			i-cache-sets = <256>;
+			d-cache-size = <0x8000>;
+			d-cache-line-size = <64>;
+			d-cache-sets = <128>;
+			next-level-cache = <&l2_cache_l>;
 		};
 
 		cpu_l2: cpu@2 {
 			device_type = "cpu";
 			compatible = "arm,cortex-a53";
 			reg = <0x0 0x2>;
 			enable-method = "psci";
 			capacity-dmips-mhz = <485>;
 			clocks = <&cru ARMCLKL>;
 			#cooling-cells = <2>; /* min followed by max */
 			dynamic-power-coefficient = <100>;
 			cpu-idle-states = <&CPU_SLEEP &CLUSTER_SLEEP>;
+			i-cache-size = <0x8000>;
+			i-cache-line-size = <64>;
+			i-cache-sets = <256>;
+			d-cache-size = <0x8000>;
+			d-cache-line-size = <64>;
+			d-cache-sets = <128>;
+			next-level-cache = <&l2_cache_l>;
 		};
 
 		cpu_l3: cpu@3 {
 			device_type = "cpu";
 			compatible = "arm,cortex-a53";
 			reg = <0x0 0x3>;
 			enable-method = "psci";
 			capacity-dmips-mhz = <485>;
 			clocks = <&cru ARMCLKL>;
 			#cooling-cells = <2>; /* min followed by max */
 			dynamic-power-coefficient = <100>;
 			cpu-idle-states = <&CPU_SLEEP &CLUSTER_SLEEP>;
+			i-cache-size = <0x8000>;
+			i-cache-line-size = <64>;
+			i-cache-sets = <256>;
+			d-cache-size = <0x8000>;
+			d-cache-line-size = <64>;
+			d-cache-sets = <128>;
+			next-level-cache = <&l2_cache_l>;
 		};
 
 		cpu_b0: cpu@100 {
 			device_type = "cpu";
 			compatible = "arm,cortex-a72";
 			reg = <0x0 0x100>;
 			enable-method = "psci";
 			capacity-dmips-mhz = <1024>;
 			clocks = <&cru ARMCLKB>;
 			#cooling-cells = <2>; /* min followed by max */
 			dynamic-power-coefficient = <436>;
 			cpu-idle-states = <&CPU_SLEEP &CLUSTER_SLEEP>;
+			i-cache-size = <0xC000>;
+			i-cache-line-size = <64>;
+			i-cache-sets = <256>;
+			d-cache-size = <0x8000>;
+			d-cache-line-size = <64>;
+			d-cache-sets = <256>;
+			next-level-cache = <&l2_cache_b>;
 
 			thermal-idle {
 				#cooling-cells = <2>;
@@ -142,14 +177,39 @@ cpu_b1: cpu@101 {
 			#cooling-cells = <2>; /* min followed by max */
 			dynamic-power-coefficient = <436>;
 			cpu-idle-states = <&CPU_SLEEP &CLUSTER_SLEEP>;
+			i-cache-size = <0xC000>;
+			i-cache-line-size = <64>;
+			i-cache-sets = <256>;
+			d-cache-size = <0x8000>;
+			d-cache-line-size = <64>;
+			d-cache-sets = <256>;
+			next-level-cache = <&l2_cache_b>;
 
 			thermal-idle {
 				#cooling-cells = <2>;
 				duration-us = <10000>;
 				exit-latency-us = <500>;
 			};
 		};
 
+		l2_cache_l: l2-cache-cluster0 {
+			compatible = "cache";
+			cache-level = <2>;
+			cache-unified;
+			cache-size = <0x80000>;
+			cache-line-size = <64>;
+			cache-sets = <512>;
+		};
+
+		l2_cache_b: l2-cache-cluster1 {
+			compatible = "cache";
+			cache-level = <2>;
+			cache-unified;
+			cache-size = <0x100000>;
+			cache-line-size = <64>;
+			cache-sets = <1024>;
+		};
+
 		idle-states {
 			entry-method = "psci";