From patchwork Wed Apr 26 11:21:48 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexandre Belloni X-Patchwork-Id: 9701203 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 92185603F6 for ; Wed, 26 Apr 2017 11:21:59 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8CEFE26223 for ; Wed, 26 Apr 2017 11:21:59 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 8044428437; Wed, 26 Apr 2017 11:21:59 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id EAF6726223 for ; Wed, 26 Apr 2017 11:21:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1954122AbdDZLV6 (ORCPT ); Wed, 26 Apr 2017 07:21:58 -0400 Received: from mail.free-electrons.com ([62.4.15.54]:46762 "EHLO mail.free-electrons.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1954121AbdDZLV5 (ORCPT ); Wed, 26 Apr 2017 07:21:57 -0400 Received: by mail.free-electrons.com (Postfix, from userid 110) id 8032F207FA; Wed, 26 Apr 2017 13:21:50 +0200 (CEST) Received: from localhost (unknown [88.191.26.124]) by mail.free-electrons.com (Postfix) with ESMTPSA id 4B8012077A; Wed, 26 Apr 2017 13:21:50 +0200 (CEST) From: Alexandre Belloni To: Boris Brezillon , Stephen Boyd , Nicolas Ferre Cc: linux-clk@vger.kernel.org, linux-kernel@vger.kernel.org, Alexandre Belloni Subject: [PATCH v2] clk: at91: Add sama5d2 suspend/resume Date: Wed, 26 Apr 2017 13:21:48 +0200 Message-Id: <20170426112148.25256-1-alexandre.belloni@free-electrons.com> X-Mailer: git-send-email 2.11.0 Sender: linux-clk-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-clk@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP On sama5d2, VDD core maybe be cut while in suspend. This means registers will be lost. Ensure they are saved and restored properly. Signed-off-by: Alexandre Belloni --- Changes in v2: - don't set MCKR or PLLAR and expect them to be properly set by the firmware/bootloader. drivers/clk/at91/pmc.c | 114 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 114 insertions(+) diff --git a/drivers/clk/at91/pmc.c b/drivers/clk/at91/pmc.c index 526df5ba042d..338cd293b356 100644 --- a/drivers/clk/at91/pmc.c +++ b/drivers/clk/at91/pmc.c @@ -13,7 +13,9 @@ #include #include #include +#include #include +#include #include @@ -41,3 +43,115 @@ int of_at91_get_clk_range(struct device_node *np, const char *propname, return 0; } EXPORT_SYMBOL_GPL(of_at91_get_clk_range); + +#ifdef CONFIG_PM +static struct regmap *pmcreg; + +static struct +{ + u32 scsr; + u32 pcsr0; + u32 uckr; + u32 mor; + u32 mcfr; + u32 pllar; + u32 mckr; + u32 usb; + u32 imr; + u32 pcsr1; + u32 pcr[64]; +} pmc_cache; + +static int pmc_suspend(void) +{ + int i; + + regmap_read(pmcreg, AT91_PMC_IMR, &pmc_cache.scsr); + regmap_read(pmcreg, AT91_PMC_PCSR, &pmc_cache.pcsr0); + regmap_read(pmcreg, AT91_CKGR_UCKR, &pmc_cache.uckr); + regmap_read(pmcreg, AT91_CKGR_MOR, &pmc_cache.mor); + regmap_read(pmcreg, AT91_CKGR_MCFR, &pmc_cache.mcfr); + regmap_read(pmcreg, AT91_CKGR_PLLAR, &pmc_cache.pllar); + regmap_read(pmcreg, AT91_PMC_MCKR, &pmc_cache.mckr); + regmap_read(pmcreg, AT91_PMC_USB, &pmc_cache.usb); + regmap_read(pmcreg, AT91_PMC_IMR, &pmc_cache.imr); + regmap_read(pmcreg, AT91_PMC_PCSR1, &pmc_cache.pcsr1); + + for (i = 2; i < 64; i++) { + regmap_write(pmcreg, AT91_PMC_PCR, (i & AT91_PMC_PCR_PID_MASK)); + regmap_read(pmcreg, AT91_PMC_PCR, &pmc_cache.pcr[i]); + } + + return 0; +} + +static bool pmc_ready(unsigned int mask) +{ + unsigned int status; + + regmap_read(pmcreg, AT91_PMC_SR, &status); + + return ((status & mask) == mask) ? 1 : 0; +} + +static void pmc_resume(void) +{ + int i; + unsigned int mask = 0; + u32 tmp; + + regmap_read(pmcreg, AT91_PMC_MCKR, &tmp); + if (pmc_cache.mckr != tmp) + pr_warn("MCKR was not configured properly by the firmware\n"); + regmap_read(pmcreg, AT91_CKGR_PLLAR, &tmp); + if (pmc_cache.pllar != tmp) + pr_warn("PLLAR was not configured properly by the firmware\n"); + + regmap_write(pmcreg, AT91_PMC_IMR, pmc_cache.scsr); + regmap_write(pmcreg, AT91_PMC_PCER, pmc_cache.pcsr0); + regmap_write(pmcreg, AT91_CKGR_UCKR, pmc_cache.uckr); + regmap_write(pmcreg, AT91_CKGR_MOR, pmc_cache.mor); + regmap_write(pmcreg, AT91_CKGR_MCFR, pmc_cache.mcfr); + regmap_write(pmcreg, AT91_PMC_USB, pmc_cache.usb); + regmap_write(pmcreg, AT91_PMC_IMR, pmc_cache.imr); + regmap_write(pmcreg, AT91_PMC_PCER1, pmc_cache.pcsr1); + + for (i = 2; i < 64; i++) { + regmap_write(pmcreg, AT91_PMC_PCR, (i & AT91_PMC_PCR_PID_MASK)); + regmap_write(pmcreg, AT91_PMC_PCR, pmc_cache.pcr[i]); + } + + if (pmc_cache.uckr & AT91_PMC_UPLLEN) + mask |= AT91_PMC_LOCKU; + + while (!pmc_ready(mask)) + cpu_relax(); +} + +static struct syscore_ops pmc_syscore_ops = { + .suspend = pmc_suspend, + .resume = pmc_resume, +}; + +static const struct of_device_id sama5d2_pmc_dt_ids[] = { + { .compatible = "atmel,sama5d2-pmc" }, + { /* sentinel */ } +}; + +static int __init pmc_register_ops(void) +{ + struct device_node *np; + + np = of_find_matching_node(NULL, sama5d2_pmc_dt_ids); + + pmcreg = syscon_node_to_regmap(np); + if (IS_ERR(pmcreg)) + return PTR_ERR(pmcreg); + + register_syscore_ops(&pmc_syscore_ops); + + return 0; +} +/* This has to happen before arch_initcall becaues of the tcb_clksrc driver */ +postcore_initcall(pmc_register_ops); +#endif