From nobody Fri Sep 25 15:15:39 2026 Received: from sender4-op-o11.zoho.com (sender4-op-o11.zoho.com [136.143.188.11]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id BAF02207DF7; Thu, 10 Sep 2026 23:02:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=pass smtp.client-ip=136.143.188.11 ARC-Seal: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789081335; cv=pass; b=tjESj23um3ObMjWFUCqHx05nF2JjXvNXoOq87O71HvGn6EW9PgdH4saA6TtYzS/bDwVpIdEVRwRauom38nsDsHQWsW+Bn0w3YwXBpFAy9DzwgLhNrG4pW+Dw18bh5TkX0TQfHG3lJpiFlLl5gGPmDvoqwC6eqiJvrFayW9z5wsA= ARC-Message-Signature: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789081335; c=relaxed/simple; bh=EysiNMAymz+CEI4gdX9gD9dZg1YUoVzI7UUvFIg8T1A=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:To:Cc; b=EUg1+KIsh844HBxFaIsIDMUZG2Ltq/BpgA0M8juaAJp3NpbNz2Lq8mg91L6zpoeu9YuoJTmEkxn+KL9O9yJ6W1c0iU1G8Dn3N5ir0LMf+bV6BUPOYENqHBOyrp7g+4LSW9FJqv3M0QqikczHQEt8Vxpkt4DgcO9FTNYZ0Aizi2g= ARC-Authentication-Results: i=2; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com; spf=pass smtp.mailfrom=collabora.com; dkim=pass (1024-bit key) header.d=collabora.com header.i=deborah.brouwer@collabora.com header.b=D5FUsM20; arc=pass smtp.client-ip=136.143.188.11 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=collabora.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=collabora.com header.i=deborah.brouwer@collabora.com header.b="D5FUsM20" ARC-Seal: i=1; a=rsa-sha256; t=1789081320; cv=none; d=zohomail.com; s=zohoarc; b=Vct1JUYy56GduX2B1Kf34yaSQbpxCJclzCyeoETz/PKJ/Ai+wgzNvTe+nbzUIZhJUWaRiPQWus5giBOHj+juyBxzLwEO2J5RYqRAZ5DGxtfrR3ngb7RD4NY0p/qW6mZf5IWOhpJWJgSdNTJliWOSYCwgpxftzWJXMC7BjBiqBWE= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1789081320; h=Content-Type:Content-Transfer-Encoding:Cc:Cc:Date:Date:From:From:MIME-Version:Message-ID:Subject:Subject:To:To:Message-Id:Reply-To; bh=YPcNiTNd+EFqHZBOKeezkN1gDau+W9MRCDQDDa3NZpM=; b=NZDDrs924TpWiX428fioqCGIRkD9dKyLfbwsI8fxAoxv90PlMhzMDIi04JCx+7yfwsHti46SmQVXCH36xJn9v6Swi9vhNykxHTXD2NjZ/fL5Xv6BDxwiIIBXz2l7CXNA1Vuog02v+eNSu8BEWbeQlMdy8/s9r/q7bBNG7IfayJU= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass header.i=collabora.com; spf=pass smtp.mailfrom=deborah.brouwer@collabora.com; dmarc=pass header.from= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; t=1789081320; s=zohomail; d=collabora.com; i=deborah.brouwer@collabora.com; h=From:From:Date:Date:Subject:Subject:MIME-Version:Content-Type:Content-Transfer-Encoding:Message-Id:Message-Id:To:To:Cc:Cc:Reply-To; bh=YPcNiTNd+EFqHZBOKeezkN1gDau+W9MRCDQDDa3NZpM=; b=D5FUsM200wVutwLdYXdllYKdOkVp0LvgDVJtIHg8qxI6KW7KD/jexLhrtBum55Pz gu+F3TyjwpPN+yoWjdufMZlJHJ/lw6ygjzWUqglCxinLeJE9NpMNO3Cp/4qetq1eUQD Ahxar1QWroU+r9q8U3f+nO35lR8tw7KQOqAzbZGM= Received: by mx.zohomail.com with SMTPS id 1789081319983511.92469138538536; Thu, 10 Sep 2026 16:01:59 -0700 (PDT) From: Deborah Brouwer Date: Thu, 10 Sep 2026 16:01:36 -0700 Subject: [PATCH] drm/tyr: reduce size of doorbell array Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20260910-b4-doorbell-v1-1-f3ca2f501600@collabora.com> X-B4-Tracking: v=1; b=H4sIAAAAAAAC/x3MQQqAIBBA0avIrBN0EMGuEi20xhoQDYUIwrsnL d/i/xcaVaYGs3ih0s2NSx7Qk4Dt9PkgyfswoEKrnFYyGLmXUgOlJBGNszZ65dHBKK5KkZ//tqy 9f5QsxNRdAAAA X-Change-ID: 20260910-b4-doorbell-224966fa0a29 To: Daniel Almeida , Alice Ryhl , Danilo Krummrich , David Airlie , Simona Vetter Cc: dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, rust-for-linux@vger.kernel.org, gary@garyguo.net, boris.brezillon@collabora.com, laura.nao@collabora.com, Deborah Brouwer X-Mailer: b4 0.14.3 X-Developer-Signature: v=1; a=openpgp-sha256; l=1973; i=deborah.brouwer@collabora.com; h=from:subject:message-id; bh=EysiNMAymz+CEI4gdX9gD9dZg1YUoVzI7UUvFIg8T1A=; b=owGbwMvMwCVWuULzOU9c7WvG02pJDFmLze6GpCndzdO5o9N06p/WRmH9HWYq70JXdik/PPah5 lzbrL8hHaUsDGJcDLJiiixn7Y16xKveG+nO/98MM4eVCWQIAxenAEzksDLDP434b2qp5dsC5l5J 9zc03lPLZPP7xyH3ikWsL53Wz8tr02T4w/1iZbn8rpS7U15ntITduViS/kGX40nJTlGT8uzH4bO PsgMA X-Developer-Key: i=deborah.brouwer@collabora.com; a=openpgp; fpr=CD3F328C177AEF322D9FFF8379A829E70C5E7DEB Currently the number of doorbells is set to 64 which is an architectural maximum for the Mali GPU major v10 supported by Tyr. Since each doorbell needs a 64 KiB page, the doorbell array alone would need 4 MiB of register memory. Since the doorbell array starts at offset 0x80000, its exclusive end would be 0x480000, but the rk3588 device that Tyr is compatible with only provides a 2 MiB iomem region in total. Reduce the number of doorbells so that they fit into the rk3588 iomem region. This is consistent with Panthor=E2=80=99s doorbell id assignment. Doorbell 0 is the global doorbell. Panthor assigns the remaining doorbells to the active command stream group (CSG) slots. The number of slots is capped at 16 (MAX_CSG_PRIO + 1). Therefore Panthor uses a maximum of 17 doorbells. The 17 doorbell pages span 0x110000 bytes. Since the doorbell array starts at offset 0x80000 its exclusive end is 0x190000 and so fits within the 2 MiB register region. Signed-off-by: Deborah Brouwer --- drivers/gpu/drm/tyr/regs.rs | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/tyr/regs.rs b/drivers/gpu/drm/tyr/regs.rs index 0c419c4e1186..68701c39aee2 100644 --- a/drivers/gpu/drm/tyr/regs.rs +++ b/drivers/gpu/drm/tyr/regs.rs @@ -1802,7 +1802,10 @@ pub(crate) mod doorbell_block { use crate::driver::TyrRegisters; =20 /// Number of doorbells available. - pub(crate) const NUM_DOORBELLS: usize =3D 64; + /// The architectural maximum is 64 but this full array does not + /// fit in the 2 MiB iomem region. Panthor currently uses a maximum of + /// 17 doorbells so do the same here. + pub(crate) const NUM_DOORBELLS: usize =3D 17; =20 /// Doorbell block stride (64KiB). /// --- base-commit: 73e5616f3d197c1af5a04a481fe0f13aa3913bd1 change-id: 20260910-b4-doorbell-224966fa0a29 Best regards, --=20 Deborah Brouwer