exo2: implement through end of random cache init

libraries/libexosphere/source/flow/flow_api.cpp

@@ -0,0 +1,51 @@
+/*
+ * Copyright (c) 2018-2020 Atmosphère-NX
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <exosphere.hpp>
+
+namespace ams::flow {
+
+    namespace {
+
+        struct FlowControllerRegisterOffset {
+            u16 cpu_csr;
+            u16 halt_cpu_events;
+            u16 cc4_core_ctrl;
+        };
+
+        constinit uintptr_t g_register_address = secmon::MemoryRegionPhysicalDeviceFlowController.GetAddress();
+
+        constexpr const FlowControllerRegisterOffset FlowControllerRegisterOffsets[] = {
+            { FLOW_CTLR_CPU0_CSR, FLOW_CTLR_HALT_CPU0_EVENTS, FLOW_CTLR_CC4_CORE0_CTRL, },
+            { FLOW_CTLR_CPU1_CSR, FLOW_CTLR_HALT_CPU1_EVENTS, FLOW_CTLR_CC4_CORE1_CTRL, },
+            { FLOW_CTLR_CPU2_CSR, FLOW_CTLR_HALT_CPU2_EVENTS, FLOW_CTLR_CC4_CORE2_CTRL, },
+            { FLOW_CTLR_CPU3_CSR, FLOW_CTLR_HALT_CPU3_EVENTS, FLOW_CTLR_CC4_CORE3_CTRL, },
+        };
+
+    }
+
+    void SetRegisterAddress(uintptr_t address) {
+        g_register_address = address;
+    }
+
+    void ResetCpuRegisters(int core) {
+        AMS_ASSUME(core >= 0);
+
+        const auto &offsets = FlowControllerRegisterOffsets[core];
+        reg::Write(g_register_address + offsets.cpu_csr,         0);
+        reg::Write(g_register_address + offsets.halt_cpu_events, 0);
+    }
+
+}