From aa6a7db50aa153fabdc45b3541e2faaa33837351 Mon Sep 17 00:00:00 2001
From: Martin Stein <martin.stein@genode-labs.com>
Date: Fri, 9 Jul 2021 14:25:46 +0200
Subject: [PATCH] base-hw: communicate kernel irqs via boot info

Core used to read the kernel-reserved IRQs from the timer objects in the
kernel's CPU objects and the PIC class (inter-processor IRQ). Besides not
being "good style" to access a kernel object in Core, this becomes a problem
when trying to prevent CPU pool from being accessed via global functions.

As a solution, this commit extends the boot info to also carry an array of all
kernel-reserved IRQs.

Ref #4217
---
 repos/base-hw/src/core/kernel/init.cc    | 10 ++++++++++
 repos/base-hw/src/core/platform.cc       |  8 +++-----
 repos/base-hw/src/include/hw/boot_info.h |  2 ++
 3 files changed, 15 insertions(+), 5 deletions(-)

diff --git a/repos/base-hw/src/core/kernel/init.cc b/repos/base-hw/src/core/kernel/init.cc
index b4ad204f18..ffd514ce8c 100644
--- a/repos/base-hw/src/core/kernel/init.cc
+++ b/repos/base-hw/src/core/kernel/init.cc
@@ -20,6 +20,7 @@
 #include <platform_pd.h>
 #include <board.h>
 #include <platform_thread.h>
+#include <hw/boot_info.h>
 
 /* base includes */
 #include <base/internal/unmanaged_singleton.h>
@@ -71,6 +72,15 @@ extern "C" void kernel_init()
 	if (Cpu::executing_id() == Cpu::primary_id()) {
 		Lock::Guard guard(data_lock());
 
+		using Boot_info = Hw::Boot_info<Board::Boot_info>;
+		Boot_info &boot_info {
+			*reinterpret_cast<Boot_info*>(Hw::Mm::boot_info().base) };
+
+		cpu_pool().for_each_cpu([&] (Kernel::Cpu &cpu) {
+			boot_info.kernel_irqs.add(cpu.timer().interrupt_id());
+		});
+		boot_info.kernel_irqs.add((unsigned)Board::Pic::IPI);
+
 		Genode::log("");
 		Genode::log("kernel initialized");
 
diff --git a/repos/base-hw/src/core/platform.cc b/repos/base-hw/src/core/platform.cc
index e54e35e276..cbbbd03f36 100644
--- a/repos/base-hw/src/core/platform.cc
+++ b/repos/base-hw/src/core/platform.cc
@@ -177,14 +177,12 @@ Platform::Platform()
 	/* make all non-kernel interrupts available to the interrupt allocator */
 	for (unsigned i = 0; i < Board::Pic::NR_OF_IRQ; i++) {
 		bool kernel_resource = false;
-		Kernel::cpu_pool().for_each_cpu([&] (Kernel::Cpu & cpu) {
-			if (i == cpu.timer().interrupt_id()) {
+		_boot_info().kernel_irqs.for_each([&] (unsigned /*idx*/,
+		                                       unsigned kernel_irq) {
+			if (i == kernel_irq) {
 				kernel_resource = true;
 			}
 		});
-		if (i == Board::Pic::IPI) {
-			kernel_resource = true;
-		}
 		if (kernel_resource) {
 			continue;
 		}
diff --git a/repos/base-hw/src/include/hw/boot_info.h b/repos/base-hw/src/include/hw/boot_info.h
index d679767f95..395455dd7c 100644
--- a/repos/base-hw/src/include/hw/boot_info.h
+++ b/repos/base-hw/src/include/hw/boot_info.h
@@ -23,10 +23,12 @@ template <typename PLAT_INFO>
 struct Hw::Boot_info
 {
 	using Mapping_pool = Genode::Array<Mapping, 32>;
+	using Kernel_irqs  = Genode::Array<unsigned, NR_OF_CPUS + 1>;
 
 	addr_t        const table;
 	addr_t        const table_allocator;
 	Mapping_pool  const elf_mappings;
+	Kernel_irqs         kernel_irqs { };
 	Mapping       const boot_modules;
 	Mmio_space    const mmio_space;
 	Memory_region_array ram_regions { };