From patchwork Mon Apr 14 05:00:04 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Simon Horman X-Patchwork-Id: 3976361 Return-Path: X-Original-To: patchwork-ltsi-dev@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id A6C60BFF02 for ; Mon, 14 Apr 2014 05:28:47 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id B550F201B4 for ; Mon, 14 Apr 2014 05:28:46 +0000 (UTC) Received: from mail.linuxfoundation.org (mail.linuxfoundation.org [140.211.169.12]) by mail.kernel.org (Postfix) with ESMTP id C20FD20120 for ; Mon, 14 Apr 2014 05:28:45 +0000 (UTC) Received: from mail.linux-foundation.org (localhost [IPv6:::1]) by mail.linuxfoundation.org (Postfix) with ESMTP id 44E888CB; Mon, 14 Apr 2014 05:28:38 +0000 (UTC) X-Original-To: ltsi-dev@lists.linuxfoundation.org Delivered-To: ltsi-dev@mail.linuxfoundation.org Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTP id AF8F6269 for ; Mon, 14 Apr 2014 05:28:36 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from kirsty.vergenet.net (kirsty.vergenet.net [202.4.237.240]) by smtp1.linuxfoundation.org (Postfix) with ESMTP id EC3E61F886 for ; Mon, 14 Apr 2014 05:28:35 +0000 (UTC) Received: from ayumi.isobedori.kobe.vergenet.net (p2020-ipbfp1604kobeminato.hyogo.ocn.ne.jp [114.154.85.20]) by kirsty.vergenet.net (Postfix) with ESMTP id 69D2C266CF1; Mon, 14 Apr 2014 15:00:10 +1000 (EST) Received: by ayumi.isobedori.kobe.vergenet.net (Postfix, from userid 7100) id A5BFEEDE63A; Mon, 14 Apr 2014 14:00:09 +0900 (JST) From: Simon Horman To: ltsi-dev@lists.linuxfoundation.org Date: Mon, 14 Apr 2014 14:00:04 +0900 Message-Id: <1397451608-19086-2-git-send-email-horms+renesas@verge.net.au> X-Mailer: git-send-email 1.8.5.2 In-Reply-To: <1397451608-19086-1-git-send-email-horms+renesas@verge.net.au> References: <1397451608-19086-1-git-send-email-horms+renesas@verge.net.au> X-Spam-Status: No, score=-2.9 required=5.0 tests=BAYES_00,RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org Cc: Magnus Damm Subject: [LTSI-dev] [PATCH] ARM: shmobile: wait for MSTP clock status to toggle, when enabling it X-BeenThere: ltsi-dev@lists.linuxfoundation.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: "A list to discuss patches, development, and other things related to the LTSI project" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: ltsi-dev-bounces@lists.linuxfoundation.org Errors-To: ltsi-dev-bounces@lists.linuxfoundation.org X-Virus-Scanned: ClamAV using ClamSMTP From: Guennadi Liakhovetski On r-/sh-mobile SoCs MSTP clocks are used by the runtime PM to dynamically enable and disable peripheral clocks. To make sure the clock has really started we have to read back its status register until it confirms success. Signed-off-by: Guennadi Liakhovetski Signed-off-by: Simon Horman (cherry picked from commit a028c6da34d434e35ba8322568c756ea97ff3c18) Signed-off-by: Simon Horman --- drivers/sh/clk/cpg.c | 38 ++++++++++++++++++++++++++++++++++++++ include/linux/sh_clk.h | 19 ++++++++++++------- 2 files changed, 50 insertions(+), 7 deletions(-) diff --git a/drivers/sh/clk/cpg.c b/drivers/sh/clk/cpg.c index 1ebe67c..7442bc1 100644 --- a/drivers/sh/clk/cpg.c +++ b/drivers/sh/clk/cpg.c @@ -36,9 +36,47 @@ static void sh_clk_write(int value, struct clk *clk) iowrite32(value, clk->mapped_reg); } +static unsigned int r8(const void __iomem *addr) +{ + return ioread8(addr); +} + +static unsigned int r16(const void __iomem *addr) +{ + return ioread16(addr); +} + +static unsigned int r32(const void __iomem *addr) +{ + return ioread32(addr); +} + static int sh_clk_mstp_enable(struct clk *clk) { sh_clk_write(sh_clk_read(clk) & ~(1 << clk->enable_bit), clk); + if (clk->status_reg) { + unsigned int (*read)(const void __iomem *addr); + int i; + void __iomem *mapped_status = (phys_addr_t)clk->status_reg - + (phys_addr_t)clk->enable_reg + clk->mapped_reg; + + if (clk->flags & CLK_ENABLE_REG_8BIT) + read = r8; + else if (clk->flags & CLK_ENABLE_REG_16BIT) + read = r16; + else + read = r32; + + for (i = 1000; + (read(mapped_status) & (1 << clk->enable_bit)) && i; + i--) + cpu_relax(); + if (!i) { + pr_err("cpg: failed to enable %p[%d]\n", + clk->enable_reg, clk->enable_bit); + return -ETIMEDOUT; + } + } return 0; } diff --git a/include/linux/sh_clk.h b/include/linux/sh_clk.h index 60c7239..1f208b2 100644 --- a/include/linux/sh_clk.h +++ b/include/linux/sh_clk.h @@ -52,6 +52,7 @@ struct clk { unsigned long flags; void __iomem *enable_reg; + void __iomem *status_reg; unsigned int enable_bit; void __iomem *mapped_reg; @@ -116,22 +117,26 @@ long clk_round_parent(struct clk *clk, unsigned long target, unsigned long *best_freq, unsigned long *parent_freq, unsigned int div_min, unsigned int div_max); -#define SH_CLK_MSTP(_parent, _enable_reg, _enable_bit, _flags) \ +#define SH_CLK_MSTP(_parent, _enable_reg, _enable_bit, _status_reg, _flags) \ { \ .parent = _parent, \ .enable_reg = (void __iomem *)_enable_reg, \ .enable_bit = _enable_bit, \ + .status_reg = _status_reg, \ .flags = _flags, \ } -#define SH_CLK_MSTP32(_p, _r, _b, _f) \ - SH_CLK_MSTP(_p, _r, _b, _f | CLK_ENABLE_REG_32BIT) +#define SH_CLK_MSTP32(_p, _r, _b, _f) \ + SH_CLK_MSTP(_p, _r, _b, 0, _f | CLK_ENABLE_REG_32BIT) -#define SH_CLK_MSTP16(_p, _r, _b, _f) \ - SH_CLK_MSTP(_p, _r, _b, _f | CLK_ENABLE_REG_16BIT) +#define SH_CLK_MSTP32_STS(_p, _r, _b, _s, _f) \ + SH_CLK_MSTP(_p, _r, _b, _s, _f | CLK_ENABLE_REG_32BIT) -#define SH_CLK_MSTP8(_p, _r, _b, _f) \ - SH_CLK_MSTP(_p, _r, _b, _f | CLK_ENABLE_REG_8BIT) +#define SH_CLK_MSTP16(_p, _r, _b, _f) \ + SH_CLK_MSTP(_p, _r, _b, 0, _f | CLK_ENABLE_REG_16BIT) + +#define SH_CLK_MSTP8(_p, _r, _b, _f) \ + SH_CLK_MSTP(_p, _r, _b, 0, _f | CLK_ENABLE_REG_8BIT) int sh_clk_mstp_register(struct clk *clks, int nr);