From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Avnish Chouhan <avnish@linux.ibm.com>
Date: Thu, 23 May 2024 18:43:14 +0530
Subject: [PATCH] kern/ieee1275/init: Add IEEE 1275 Radix support for KVM on
 Power

This patch adds support for Radix, Xive and Radix_gtse in Options
vector5 which is required for KVM LPARs. KVM LPARs ONLY support
Radix and not the Hash. Not enabling Radix on any PowerVM KVM LPARs
will result in boot failure.

Signed-off-by: Avnish Chouhan <avnish@linux.ibm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
---
 grub-core/kern/ieee1275/init.c | 63 +++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 62 insertions(+), 1 deletion(-)

diff --git a/grub-core/kern/ieee1275/init.c b/grub-core/kern/ieee1275/init.c
index 13e8a5b4bb8..6c5f4fb77af 100644
--- a/grub-core/kern/ieee1275/init.c
+++ b/grub-core/kern/ieee1275/init.c
@@ -113,6 +113,16 @@ grub_addr_t grub_ieee1275_original_stack;
 #define DRC_INFO            0x40
 #define BYTE22              (DY_MEM_V2 | DRC_INFO)
 
+/* For ibm,arch-vec-5-platform-support. */
+#define XIVE_INDEX           0x17
+#define MMU_INDEX            0x18
+#define RADIX_GTSE_INDEX     0x1a
+#define RADIX_ENABLED        0x40
+#define XIVE_ENABLED         0x40
+#define HASH_ENABLED         0x00
+#define MAX_SUPPORTED        0xC0
+#define RADIX_GTSE_ENABLED   0x40
+
 void
 grub_exit (int rc __attribute__((unused)))
 {
@@ -739,6 +749,10 @@ struct option_vector5
   grub_uint32_t platform_facilities;
   grub_uint8_t sub_processors;
   grub_uint8_t byte22;
+  grub_uint8_t xive;
+  grub_uint8_t mmu;
+  grub_uint8_t hpt_ext;
+  grub_uint8_t radix_gtse;
 } GRUB_PACKED;
 
 struct pvr_entry
@@ -777,6 +791,13 @@ grub_ieee1275_ibm_cas (void)
 {
   int rc;
   grub_ieee1275_ihandle_t root;
+  grub_uint8_t ibm_arch_platform_support[8];
+  grub_ssize_t actual;
+  grub_uint8_t xive_support = 0;
+  grub_uint8_t mmu_support = 0;
+  grub_uint8_t radix_gtse_support = 0;
+  int i = 0;
+  int prop_len = 8;
   struct cas_args
   {
     struct grub_ieee1275_common_hdr common;
@@ -785,6 +806,46 @@ grub_ieee1275_ibm_cas (void)
     grub_ieee1275_cell_t cas_addr;
     grub_ieee1275_cell_t result;
   } args;
+
+  grub_ieee1275_get_integer_property (grub_ieee1275_chosen,
+                                      "ibm,arch-vec-5-platform-support",
+                                      (grub_uint32_t *) ibm_arch_platform_support,
+                                      sizeof (ibm_arch_platform_support),
+                                      &actual);
+
+  for (i = 0; i < prop_len; i++)
+    {
+      switch (ibm_arch_platform_support[i])
+        {
+          case XIVE_INDEX:
+            if (ibm_arch_platform_support[i + 1] & MAX_SUPPORTED)
+              xive_support = XIVE_ENABLED;
+            else
+              xive_support = 0;
+            break;
+
+          case MMU_INDEX:
+            if (ibm_arch_platform_support[i + 1] & MAX_SUPPORTED)
+              mmu_support = RADIX_ENABLED;
+            else
+              mmu_support = HASH_ENABLED;
+            break;
+
+          case RADIX_GTSE_INDEX:
+            if (mmu_support == RADIX_ENABLED)
+              radix_gtse_support = ibm_arch_platform_support[i + 1] & RADIX_GTSE_ENABLED;
+            else
+              radix_gtse_support = 0;
+            break;
+
+          default:
+            /* Ignoring the other indexes of ibm,arch-vec-5-platform-support. */
+            break;
+        }
+      /* Skipping the property value. */
+      i++;
+    }
+
   struct cas_vector vector =
   {
     .pvr_list = { { 0x00000000, 0xffffffff } }, /* any processor */
@@ -801,7 +862,7 @@ grub_ieee1275_ibm_cas (void)
     .vec4 = 0x0001, /* set required minimum capacity % to the lowest value */
     .vec5_size = 1 + sizeof (struct option_vector5) - 2,
     .vec5 = {
-      0, BYTE2, 0, CMO, ASSOCIATIVITY, BIN_OPTS, 0, 0, MAX_CPU, 0, 0, PLATFORM_FACILITIES, SUB_PROCESSORS, BYTE22
+      0, BYTE2, 0, CMO, ASSOCIATIVITY, BIN_OPTS, 0, 0, MAX_CPU, 0, 0, PLATFORM_FACILITIES, SUB_PROCESSORS, BYTE22, xive_support, mmu_support, 0, radix_gtse_support
     }
   };