Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753349Ab3ISTMf (ORCPT ); Thu, 19 Sep 2013 15:12:35 -0400 Received: from mail-bk0-f48.google.com ([209.85.214.48]:48685 "EHLO mail-bk0-f48.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752120Ab3ISTMe (ORCPT ); Thu, 19 Sep 2013 15:12:34 -0400 Message-ID: <523B4C9B.6000002@gmail.com> Date: Thu, 19 Sep 2013 21:12:27 +0200 From: Sebastian Hesselbarth User-Agent: Mozilla/5.0 (X11; Linux i686 on x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.0 To: Tony Prisk CC: Olof Johansson , Arnd Bergmann , Mike Turquette , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 07/26] clk: vt8500: parse pmc_base from clock driver References: <1379526839-14798-1-git-send-email-sebastian.hesselbarth@gmail.com> <1379526839-14798-8-git-send-email-sebastian.hesselbarth@gmail.com> <523B4A51.4020704@prisktech.co.nz> In-Reply-To: <523B4A51.4020704@prisktech.co.nz> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3986 Lines: 120 On 09/19/2013 09:02 PM, Tony Prisk wrote: > On 19/09/13 05:53, Sebastian Hesselbarth wrote: >> Currently, clock providers for vt8500 depend on machine_init providing >> pmc_base address before calling of_clk_init. With upcoming arch-wide >> .time_init calling of_clk_init, we should make clock providers >> independent >> of mach code. This adds a pmc_base parsing helper to current clock >> provider >> that gets called if there is no pmc_base set, yet. >> >> Signed-off-by: Sebastian Hesselbarth >> --- >> Cc: Olof Johansson >> Cc: Arnd Bergmann >> Cc: Tony Prisk >> Cc: Mike Turquette >> Cc: linux-arm-kernel@lists.infradead.org >> Cc: linux-kernel@vger.kernel.org >> --- >> drivers/clk/clk-vt8500.c | 21 +++++++++++++++++++++ >> 1 file changed, 21 insertions(+) >> >> diff --git a/drivers/clk/clk-vt8500.c b/drivers/clk/clk-vt8500.c >> index 82306f5..a5ee01c 100644 >> --- a/drivers/clk/clk-vt8500.c >> +++ b/drivers/clk/clk-vt8500.c >> @@ -15,11 +15,14 @@ >> #include >> #include >> +#include >> #include >> #include >> #include >> #include >> +#define LEGACY_PMC_BASE 0xD8130000 >> + >> /* All clocks share the same lock as none can be changed >> concurrently */ >> static DEFINE_SPINLOCK(_lock); >> @@ -626,6 +629,21 @@ const struct clk_ops vtwm_pll_ops = { >> .recalc_rate = vtwm_pll_recalc_rate, >> }; >> +static __init void vtwm_set_pmc_base(void) >> +{ >> + struct device_node *np = >> + of_find_compatible_node(NULL, NULL, "via,vt8500-pmc"); >> + >> + if (np) >> + pmc_base = of_iomap(np, 0); >> + else >> + pmc_base = ioremap(LEGACY_PMC_BASE, 0x1000); >> + of_node_put(np); >> + >> + if (!pmc_base) >> + pr_err("%s:of_iomap(pmc) failed\n", __func__); >> +} >> + >> static __init void vtwm_pll_clk_init(struct device_node *node, int >> pll_type) >> { >> u32 reg; >> @@ -636,6 +654,9 @@ static __init void vtwm_pll_clk_init(struct >> device_node *node, int pll_type) >> struct clk_init_data init; >> int rc; >> + if (!pmc_base) >> + vtwm_set_pmc_base(); >> + >> rc = of_property_read_u32(node, "reg", ®); >> if (WARN_ON(rc)) >> return; > What happens if the first clock registered is a 'device clock' rather > than a 'pll'? > > static __init void vtwm_device_clk_init(struct device_node *node) > { > u32 en_reg, div_reg; > struct clk *clk; > struct clk_device *dev_clk; > const char *clk_name = node->name; > const char *parent_name; > struct clk_init_data init; > int rc; > int clk_init_flags = 0; > > dev_clk = kzalloc(sizeof(*dev_clk), GFP_KERNEL); > if (WARN_ON(!dev_clk)) > return; > > dev_clk->lock = &_lock; > > rc = of_property_read_u32(node, "enable-reg", &en_reg); > if (!rc) { > dev_clk->en_reg = pmc_base + en_reg; > ... > } > CLK_OF_DECLARE(vt8500_device, "via,vt8500-device-clock", > vtwm_device_clk_init); > > If a device clock is initialized first, pmc_base will be null and > dev_clk->en_reg (+ other register offsets) will be incorrect. Tony, looks like I just missed to add the same check for !pmc_base to vtwm_device_clk_init. If you are ok with the general approach, I send v2 for this patch shortly. Optionally, you can also choose to take care of clk-vt8500 yourself, as mach-vt8500 has its own .init_time callback and will be unaffected by the arch-wide default callback. If so, I will drop vt8500 to not stall this series too much now. Sebastian -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/