From patchwork Wed Jan 30 09:33:55 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: ARM i.MX25: clk: parent per5_clk to AHB clock From: Steffen Trumtrar X-Patchwork-Id: 216798 Message-Id: <1359538435-21304-1-git-send-email-s.trumtrar@pengutronix.de> To: linux-arm-kernel@lists.infradead.org Cc: Steffen Trumtrar , Russell King , stable@vger.kernel.org, Sascha Hauer Date: Wed, 30 Jan 2013 10:33:55 +0100 The mxc-timer on the imx25 needs to be derived from the AHB clock. If a bootloader reparents this clock to the ipg_clk_highfreq, which according to the datasheet is a valid operation, the system can/will produce lockups/ freezes after some time [1]. This can be forced with code like while(1) syscall(SYS_clock_gettime, CLOCK_REALTIME, &tp); This was already fixed with the commit "i.MX25 GPT clock fix: ensure correct the clock source" [2], but it seems, that it got lost. So, re-add this to have a correct gpt. [1]: http://lists.arm.linux.org.uk/lurker/message/20130129.161230.229bda17.en.html [2]: 2012d9ca2a1381ae3e733330a7f0d1d2f1988bba Signed-off-by: Steffen Trumtrar Cc: stable@vger.kernel.org --- arch/arm/mach-imx/clk-imx25.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/arm/mach-imx/clk-imx25.c b/arch/arm/mach-imx/clk-imx25.c index 5d34f67..0e6dde6 100644 --- a/arch/arm/mach-imx/clk-imx25.c +++ b/arch/arm/mach-imx/clk-imx25.c @@ -177,6 +177,9 @@ static int __init __mx25_clocks_init(unsigned long osc_rate) pr_err("i.MX25 clk %d: register failed with %ld\n", i, PTR_ERR(clk[i])); + /* Clock source for gpt must be derived from AHB */ + clk_set_parent(clk[per5_sel], clk[ahb]); + clk_register_clkdev(clk[ipg], "ipg", "imx-gpt.0"); clk_register_clkdev(clk[gpt_ipg_per], "per", "imx-gpt.0");