All of lore.kernel.org
 help / color / mirror / Atom feed
From: Nicholas Piggin <npiggin@gmail.com>
To: qemu-devel@nongnu.org
Cc: Nicholas Piggin <npiggin@gmail.com>,
	qemu-ppc@nongnu.org, qemu-stable@nongnu.org
Subject: [PULL 1/2] target/ppc: Big-core scratch register fix
Date: Tue,  8 Apr 2025 22:45:48 +1000	[thread overview]
Message-ID: <20250408124550.40485-2-npiggin@gmail.com> (raw)
In-Reply-To: <20250408124550.40485-1-npiggin@gmail.com>

The per-core SCRATCH0-7 registers are shared between big cores, which
was missed in the big-core implementation. It is difficult to model
well with the big-core == 2xPnvCore scheme we moved to, this fix
uses the even PnvCore to store the scrach data.

Also remove a stray log message that came in with the same patch that
introduced patch.

Fixes: c26504afd5f5c ("ppc/pnv: Add a big-core mode that joins two regular cores")
Cc: qemu-stable@nongnu.org
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 target/ppc/misc_helper.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/target/ppc/misc_helper.c b/target/ppc/misc_helper.c
index 2d9512c116..46ae454afd 100644
--- a/target/ppc/misc_helper.c
+++ b/target/ppc/misc_helper.c
@@ -332,6 +332,10 @@ target_ulong helper_load_sprd(CPUPPCState *env)
     PnvCore *pc = pnv_cpu_state(cpu)->pnv_core;
     target_ulong sprc = env->spr[SPR_POWER_SPRC];
 
+    if (pc->big_core) {
+        pc = pnv_chip_find_core(pc->chip, CPU_CORE(pc)->core_id & ~0x1);
+    }
+
     switch (sprc & 0x3e0) {
     case 0: /* SCRATCH0-3 */
     case 1: /* SCRATCH4-7 */
@@ -368,6 +372,10 @@ void helper_store_sprd(CPUPPCState *env, target_ulong val)
     PnvCore *pc = pnv_cpu_state(cpu)->pnv_core;
     int nr;
 
+    if (pc->big_core) {
+        pc = pnv_chip_find_core(pc->chip, CPU_CORE(pc)->core_id & ~0x1);
+    }
+
     switch (sprc & 0x3e0) {
     case 0: /* SCRATCH0-3 */
     case 1: /* SCRATCH4-7 */
@@ -378,7 +386,6 @@ void helper_store_sprd(CPUPPCState *env, target_ulong val)
          * information. Could also dump these upon checkstop.
          */
         nr = (sprc >> 3) & 0x7;
-        qemu_log("SPRD write 0x" TARGET_FMT_lx " to SCRATCH%d\n", val, nr);
         pc->scratch[nr] = val;
         break;
     default:
-- 
2.47.1



  reply	other threads:[~2025-04-08 12:46 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-04-08 12:45 [PULL 0/2] ppc-for-10.0-3 queue Nicholas Piggin
2025-04-08 12:45 ` Nicholas Piggin [this message]
2025-04-24  8:25   ` [PULL 1/2] target/ppc: Big-core scratch register fix Thomas Huth
2025-04-30  0:00     ` Nicholas Piggin
2025-04-30  5:56       ` Thomas Huth
2025-04-08 12:45 ` [PULL 2/2] target/ppc: Fix SPRC/SPRD SPRs for P9/10 Nicholas Piggin
2025-04-09  8:31 ` [PULL 0/2] ppc-for-10.0-3 queue Stefan Hajnoczi

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20250408124550.40485-2-npiggin@gmail.com \
    --to=npiggin@gmail.com \
    --cc=qemu-devel@nongnu.org \
    --cc=qemu-ppc@nongnu.org \
    --cc=qemu-stable@nongnu.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.