From patchwork Mon Dec 23 08:37:03 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Chen-Yu Tsai X-Patchwork-Id: 3396161 Return-Path: X-Original-To: patchwork-linux-arm@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 7771DC0D4A for ; Mon, 23 Dec 2013 08:41:27 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 83276201F2 for ; Mon, 23 Dec 2013 08:41:26 +0000 (UTC) Received: from casper.infradead.org (casper.infradead.org [85.118.1.10]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 74E3C201C8 for ; Mon, 23 Dec 2013 08:41:25 +0000 (UTC) Received: from merlin.infradead.org ([2001:4978:20e::2]) by casper.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1Vv134-0000Pb-NA; Mon, 23 Dec 2013 08:39:39 +0000 Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1Vv12d-0003Yf-54; Mon, 23 Dec 2013 08:39:11 +0000 Received: from mirror2.csie.ntu.edu.tw ([140.112.30.76]) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1Vv11j-0003Tm-7s for linux-arm-kernel@lists.infradead.org; Mon, 23 Dec 2013 08:38:18 +0000 Received: from wens by mirror2.csie.ntu.edu.tw with local (Exim 4.82) (envelope-from ) id 1Vv115-0002xX-QW; Mon, 23 Dec 2013 16:37:35 +0800 From: Chen-Yu Tsai To: emilio@elopez.com.ar, Mike Turquette , Maxime Ripard Subject: [PATCH 1/4] clk: sunxi: Allwinner A20 output clock support Date: Mon, 23 Dec 2013 16:37:03 +0800 Message-Id: <1387787827-11341-2-git-send-email-wens@csie.org> X-Mailer: git-send-email 1.8.5.2 In-Reply-To: <1387787827-11341-1-git-send-email-wens@csie.org> References: <1387787827-11341-1-git-send-email-wens@csie.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20131223_033815_509702_BC202200 X-CRM114-Status: GOOD ( 12.97 ) X-Spam-Score: -2.4 (--) Cc: linux-sunxi@googlegroups.com, Chen-Yu Tsai , linux-arm-kernel@lists.infradead.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.7 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 X-Virus-Scanned: ClamAV using ClamSMTP This patch adds support for the external clock outputs on the Allwinner A20 SoC. The clock outputs are similar to "module 0" type clocks, with different offsets and widths for clock factors. Signed-off-by: Chen-Yu Tsai Acked-by: Emilio López --- drivers/clk/sunxi/clk-sunxi.c | 57 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 57 insertions(+) diff --git a/drivers/clk/sunxi/clk-sunxi.c b/drivers/clk/sunxi/clk-sunxi.c index 25d99b6..19d9e9e 100644 --- a/drivers/clk/sunxi/clk-sunxi.c +++ b/drivers/clk/sunxi/clk-sunxi.c @@ -330,6 +330,47 @@ static void sun4i_get_mod0_factors(u32 *freq, u32 parent_rate, /** + * sun7i_a20_get_out_factors() - calculates m, p factors for CLK_OUT_A/B + * CLK_OUT rate is calculated as follows + * rate = (parent_rate >> p) / (m + 1); + */ + +static void sun7i_a20_get_out_factors(u32 *freq, u32 parent_rate, + u8 *n, u8 *k, u8 *m, u8 *p) +{ + u8 div, calcm, calcp; + + /* These clocks can only divide, so we will never be able to achieve + * frequencies higher than the parent frequency */ + if (*freq > parent_rate) + *freq = parent_rate; + + div = parent_rate / *freq; + + if (div < 32) + calcp = 0; + else if (div / 2 < 32) + calcp = 1; + else if (div / 4 < 32) + calcp = 2; + else + calcp = 3; + + calcm = DIV_ROUND_UP(div, 1 << calcp); + + *freq = (parent_rate >> calcp) / calcm; + + /* we were called to round the frequency, we can now return */ + if (n == NULL) + return; + + *m = calcm - 1; + *p = calcp; +} + + + +/** * sunxi_factors_clk_setup() - Setup function for factor clocks */ @@ -384,6 +425,14 @@ static struct clk_factors_config sun4i_mod0_config = { .pwidth = 2, }; +/* user manual says "n" but it's really "p" */ +static struct clk_factors_config sun7i_a20_out_config = { + .mshift = 8, + .mwidth = 5, + .pshift = 20, + .pwidth = 2, +}; + static const struct factors_data sun4i_pll1_data __initconst = { .enable = 31, .table = &sun4i_pll1_config, @@ -414,6 +463,13 @@ static const struct factors_data sun4i_mod0_data __initconst = { .getter = sun4i_get_mod0_factors, }; +static const struct factors_data sun7i_a20_out_data __initconst = { + .enable = 31, + .mux = 24, + .table = &sun7i_a20_out_config, + .getter = sun7i_a20_get_out_factors, +}; + static struct clk * __init sunxi_factors_clk_setup(struct device_node *node, const struct factors_data *data) { @@ -912,6 +968,7 @@ static const struct of_device_id clk_factors_match[] __initconst = { {.compatible = "allwinner,sun6i-a31-pll1-clk", .data = &sun6i_a31_pll1_data,}, {.compatible = "allwinner,sun4i-apb1-clk", .data = &sun4i_apb1_data,}, {.compatible = "allwinner,sun4i-mod0-clk", .data = &sun4i_mod0_data,}, + {.compatible = "allwinner,sun7i-a20-out-clk", .data = &sun7i_a20_out_data,}, {} };