From 3707e5708e1e6566c568bcf2755135864945577b Mon Sep 17 00:00:00 2001
From: Rodrigo Arias Mallo <rodrigo.arias@bsc.es>
Date: Mon, 22 Jan 2024 13:35:21 +0100
Subject: [PATCH] Disable EFI in the kernel and use normal stdenv

In order to build the kernel without compressed instructions we need to
disable EFI support. We also need to leave the kernel to figure the
proper -march and -mabi flags, as otherwise it fails to build. Using the
option "CONFIG_RISCV_ISA_C n" disables the use of compressed
instructions.
---
 overlay.nix | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/overlay.nix b/overlay.nix
index 6578708..628a773 100644
--- a/overlay.nix
+++ b/overlay.nix
@@ -51,6 +51,9 @@ final: prev:
   });
 
   linuxPackagesCustom = prev.linuxPackagesFor (prev.linux.override {
+    # Don't use a compiler without compressed instructions, let the kernel
+    # configure the -march and -mabi arguments.
+    stdenv = prev.stdenv;
     structuredExtraConfig = with prev.lib.kernel; {
       KEXEC = yes;
       SERIAL_8250_DW = yes;
@@ -82,6 +85,8 @@ final: prev:
       PCI_HOST_GENERIC = yes;
 
       RISCV_ISA_C = no;
+      NONPORTABLE = yes;
+      EFI = no;
     };
   });
 }