kernel_ldr: finish implementing all core logic.

libraries/libmesosphere/source/arch/arm64/kern_cpu.cpp

@@ -0,0 +1,69 @@
+/*
+ * Copyright (c) 2018-2019 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 <mesosphere.hpp>
+
+namespace ams::kern::arm64::cpu {
+
+    namespace {
+
+        void FlushEntireDataCacheImpl(int level) {
+            /* Used in multiple locations. */
+            const u64 level_sel_value = static_cast<u64>(level << 1);
+
+            /* Set selection register. */
+            cpu::SetCsselrEl1(level_sel_value);
+            cpu::InstructionMemoryBarrier();
+
+            /* Get cache size id info. */
+            CacheSizeIdAccessor ccsidr_el1;
+            const int num_sets  = ccsidr_el1.GetNumberOfSets();
+            const int num_ways  = ccsidr_el1.GetAssociativity();
+            const int line_size = ccsidr_el1.GetLineSize();
+
+            const u64 way_shift = static_cast<u64>(__builtin_clz(num_ways));
+            const u64 set_shift = static_cast<u64>(line_size + 4);
+
+            for (int way = 0; way <= num_ways; way++) {
+                for (int set = 0; set <= num_sets; set++) {
+                    const u64 way_value  = static_cast<u64>(way) << way_shift;
+                    const u64 set_value  = static_cast<u64>(set) << set_shift;
+                    const u64 cisw_value = way_value | set_value | level_sel_value;
+                    __asm__ __volatile__("dc cisw, %0" ::"r"(cisw_value) : "memory");
+                }
+            }
+        }
+
+    }
+
+    void FlushEntireDataCacheShared() {
+        CacheLineIdAccessor clidr_el1;
+        const int levels_of_coherency   = clidr_el1.GetLevelsOfCoherency();
+        const int levels_of_unification = clidr_el1.GetLevelsOfUnification();
+
+        for (int level = levels_of_coherency; level >= levels_of_unification; level--) {
+            FlushEntireDataCacheImpl(level);
+        }
+    }
+
+    void FlushEntireDataCacheLocal() {
+        CacheLineIdAccessor clidr_el1;
+        const int levels_of_unification = clidr_el1.GetLevelsOfUnification();
+
+        for (int level = levels_of_unification - 1; level >= 0; level--) {
+            FlushEntireDataCacheImpl(level);
+        }
+    }
+}

libraries/libmesosphere/source/board/nintendo/switch/kern_k_system_control.cpp

@@ -39,6 +39,12 @@ namespace ams::kern {
             return value;
         }
 
+        inline u64 GenerateRandomU64() {
+            u64 value;
+            smc::GenerateRandomBytes(&value, sizeof(value));
+            return value;
+        }
+
         inline smc::MemoryMode GetMemoryMode() {
             return static_cast<smc::MemoryMode>((GetKernelConfiguration() >> 10) & 0x3);
         }
@@ -73,6 +79,24 @@ namespace ams::kern {
         return (GetKernelConfiguration() >> 3) & 1;
     }
 
+    /* Randomness. */
+    void KSystemControl::GenerateRandomBytes(void *dst, size_t size) {
+        MESOSPHERE_ABORT_UNLESS(size <= 0x38);
+        smc::GenerateRandomBytes(dst, size);
+    }
+
+    u64 KSystemControl::GenerateRandomRange(u64 min, u64 max) {
+        /* This is a biased random, but this is okay for now. */
+        /* TODO: unbiased random? */
+        const u64 range_size    = ((max + 1) - min);
+        const u64 effective_max = (std::numeric_limits<u64>::max() / range_size) * range_size;
+        while (true) {
+            if (const u64 rnd = GenerateRandomU64(); rnd < effective_max) {
+                return rnd % effective_max;
+            }
+        }
+    }
+
     void KSystemControl::StopSystem() {
         /* Display a panic screen via exosphere. */
         smc::Panic(0xF00);

libraries/libmesosphere/source/board/nintendo/switch/kern_secure_monitor.cpp

@@ -80,6 +80,18 @@ namespace ams::kern::smc {
         }
     }
 
+    void GenerateRandomBytes(void *dst, size_t size) {
+        /* Call SmcGenerateRandomBytes() */
+        /* TODO: Lock this to ensure only one core calls at once. */
+        SecureMonitorArguments args = { FunctionId_GetConfig, size };
+        MESOSPHERE_ABORT_UNLESS(size <= sizeof(args) - sizeof(args.x[0]));
+        CallPrivilegedSecureMonitorFunction(args);
+        MESOSPHERE_ABORT_UNLESS((static_cast<SmcResult>(args.x[0]) == SmcResult::Success));
+
+        /* Copy output. */
+        std::memcpy(dst, &args.x[1], size);
+    }
+
     void NORETURN Panic(u32 color) {
         SecureMonitorArguments args = { FunctionId_Panic, color };
         CallPrivilegedSecureMonitorFunction(args);

libraries/libmesosphere/source/board/nintendo/switch/kern_secure_monitor.hpp

@@ -65,6 +65,7 @@ namespace ams::kern::smc {
 
     /* TODO: Rest of Secure Monitor API. */
     void GetConfig(u64 *out, size_t num_qwords, ConfigItem config_item);
+    void GenerateRandomBytes(void *dst, size_t size);
     void NORETURN Panic(u32 color);
     bool ReadWriteRegister(u32 *out, u64 address, u32 mask, u32 value);