From patchwork Mon Apr 28 00:38:42 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Simon Horman X-Patchwork-Id: 4073201 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 E9967BFF02 for ; Mon, 28 Apr 2014 00:39:28 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 0BE8720218 for ; Mon, 28 Apr 2014 00:39:28 +0000 (UTC) Received: from mail.linuxfoundation.org (mail.linuxfoundation.org [140.211.169.12]) by mail.kernel.org (Postfix) with ESMTP id 1F70A2020E for ; Mon, 28 Apr 2014 00:39:27 +0000 (UTC) Received: from mail.linux-foundation.org (localhost [IPv6:::1]) by mail.linuxfoundation.org (Postfix) with ESMTP id 25044A82; Mon, 28 Apr 2014 00:39:08 +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 EF20F92F for ; Mon, 28 Apr 2014 00:39:06 +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 8927320114 for ; Mon, 28 Apr 2014 00:39:05 +0000 (UTC) Received: from ayumi.isobedori.kobe.vergenet.net (p2182-ipbfp905kobeminato.hyogo.ocn.ne.jp [122.21.197.182]) by kirsty.vergenet.net (Postfix) with ESMTP id 53C19266CEF; Mon, 28 Apr 2014 10:39:01 +1000 (EST) Received: by ayumi.isobedori.kobe.vergenet.net (Postfix, from userid 7100) id A43A8EDE6F6; Mon, 28 Apr 2014 09:38:54 +0900 (JST) From: Simon Horman To: ltsi-dev@lists.linuxfoundation.org Date: Mon, 28 Apr 2014 09:38:42 +0900 Message-Id: <1398645529-32321-5-git-send-email-horms+renesas@verge.net.au> X-Mailer: git-send-email 1.8.5.2 In-Reply-To: <1398645529-32321-1-git-send-email-horms+renesas@verge.net.au> References: <1398645529-32321-1-git-send-email-horms+renesas@verge.net.au> X-Spam-Status: No, score=-4.8 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, 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 v2 04/11] 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);