From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-18.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B35E2C43457 for ; Sat, 17 Oct 2020 05:37:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6E6CA206E5 for ; Sat, 17 Oct 2020 05:37:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1602913043; bh=wpHHkpSSM4GJrfAVokKmd5/Sksc+zajepbEU8E6FKKw=; h=From:To:Cc:Subject:Date:List-ID:From; b=bOGZdnSEw3KF6fm8dO8FFxVQtHKN1EaZv1P5ogcO1oTISKoDURy4i2Mt53F6QDeWg spdAKceX3PS7N+T6Bj7DsFL1kxI7o26BykFNEmvsEO+jnesGIXeng2MdycHKh2TZd8 +nlLNo/jvxQBM8avtLttLTBpE5fAqCQS1qCbhvno= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2411826AbgJQFhW (ORCPT ); Sat, 17 Oct 2020 01:37:22 -0400 Received: from mail.kernel.org ([198.145.29.99]:43042 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2411472AbgJQFhV (ORCPT ); Sat, 17 Oct 2020 01:37:21 -0400 Received: from mail.kernel.org (unknown [104.132.1.79]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 0D205207BC; Sat, 17 Oct 2020 02:01:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1602900098; bh=wpHHkpSSM4GJrfAVokKmd5/Sksc+zajepbEU8E6FKKw=; h=From:To:Cc:Subject:Date:From; b=RRxUJMkGM/FWKah4086J64u71LxphKynJzZrkX/5UlfClBO1pt0VPETpfzmV/iWCX MM7f54KEepOPQuvVxbwGRbqEY5mrNs5CPdISa5GM1jn4Pyjmk1GNsd3ym9Li0DqY+j KlVYSJ6DMQHhg14/0nRg/f1DfbvksiUTUte9Pgbk= From: Stephen Boyd To: Michael Turquette , Stephen Boyd Cc: linux-kernel@vger.kernel.org, linux-clk@vger.kernel.org, Douglas Anderson , Taniya Das , Rajendra Nayak Subject: [PATCH] clk: qcom: gdsc: Keep RETAIN_FF bit set if gdsc is already on Date: Fri, 16 Oct 2020 19:01:37 -0700 Message-Id: <20201017020137.1251319-1-sboyd@kernel.org> X-Mailer: git-send-email 2.29.0.rc1.297.gfa9743e501-goog MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org If the GDSC is enabled out of boot but doesn't have the retain ff bit set we will get confusing results where the registers that are powered by the GDSC lose their contents on the first power off of the GDSC but thereafter they retain their contents. This is because gdsc_init() fails to make sure the RETAIN_FF bit is set when it probes the GDSC the first time and thus powering off the GDSC causes the register contents to be reset. We do set the RETAIN_FF bit the next time we power on the GDSC, see gdsc_enable(), so that subsequent GDSC power off's don't lose register contents state. Forcibly set the bit at device probe time so that the kernel's assumed view of the GDSC is consistent with the state of the hardware. This fixes a problem where the audio PLL doesn't work on sc7180 when the bootloader leaves the lpass_core_hm GDSC enabled at boot (e.g. to make a noise) but critically doesn't set the RETAIN_FF bit. Cc: Douglas Anderson Cc: Taniya Das Cc: Rajendra Nayak Fixes: 173722995cdb ("clk: qcom: gdsc: Add support to enable retention of GSDCR") Signed-off-by: Stephen Boyd --- drivers/clk/qcom/gdsc.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/clk/qcom/gdsc.c b/drivers/clk/qcom/gdsc.c index bfc4ac02f9ea..af26e0695b86 100644 --- a/drivers/clk/qcom/gdsc.c +++ b/drivers/clk/qcom/gdsc.c @@ -358,6 +358,14 @@ static int gdsc_init(struct gdsc *sc) if ((sc->flags & VOTABLE) && on) gdsc_enable(&sc->pd); + /* + * Make sure the retain bit is set if the GDSC is already on, otherwise + * we end up turning off the GDSC and destroying all the register + * contents that we thought we were saving. + */ + if ((sc->flags & RETAIN_FF_ENABLE) && on) + gdsc_retain_ff_on(sc); + /* If ALWAYS_ON GDSCs are not ON, turn them ON */ if (sc->flags & ALWAYS_ON) { if (!on) base-commit: 9ff9b0d392ea08090cd1780fb196f36dbb586529 -- https://git.kernel.org/pub/scm/linux/kernel/git/clk/linux.git/