From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from nz-out-0506.google.com (nz-out-0506.google.com [64.233.162.237]) by ozlabs.org (Postfix) with ESMTP id 0BB67DDDFA for ; Fri, 30 Nov 2007 06:05:48 +1100 (EST) Received: by nz-out-0506.google.com with SMTP id i1so1529784nzh for ; Thu, 29 Nov 2007 11:05:47 -0800 (PST) Message-ID: Date: Thu, 29 Nov 2007 12:05:45 -0700 From: "Alan Bennett" Sender: alan@akb.net To: "Vitaly Bordug" Subject: Re: Timers on mpc8248 etc... In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 References: <474DFD15.603@freescale.com> <20071129143159.2538786d@kernel.crashing.org> Cc: linuxppc-dev@ozlabs.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Though I'd like to move to a uboot fdt, I can't afford to port it yet, maybe in January. But until then ... It appears that a simple change in U-boot constant, #define CONFIG_8260_CLKIN 66000000 /* in Hz */ to #define CONFIG_8260_CLKIN 100000000 /* in Hz */ has fixed the speed mismatch, and I've verified that schedule_timeout(HZ/10) produces a 100 millisecond delay. However, my serial ports (brgs) are hosed. -Alan On 11/29/07, Alan Bennett wrote: > My uboot is new-ish, but I don't have the fdt commands? U-Boot 1.3.0 > g992742a5-dirty > > u-boot:clock configuration > =========================== > MPC8248 Clock Configuration > - Bus-to-Core Mult 3.5x, VCO Div 2, 60x Bus Freq 30-85 , Core Freq 100-300 > - dfbrg 1, corecnf 0x1e, busdf 3, cpmdf 1, plldf 0, pllmf 5, pcidf 5 > - vco_out 396000000, scc_clk 99000000, brg_clk 24750000 > - cpu_clk 231000000, cpm_clk 198000000, bus_clk 66000000 > > Boot Wrapper Reporting > =========================== > Memory <- <0x0 0x8000000> (128MB) > CPU clock-frequency <- 0xdc4c7c0 (231MHz) > CPU timebase-frequency <- 0xfbc520 (17MHz) > CPU bus-frequency <- 0x3ef1480 (66MHz) > > Kernel reporting > =========================== > clocksource: timebase mult[f26c9b2] shift[22] registered > > device tree in kernel (hex= `od -x`: > =========================== > /proc/device-tree/cpus/PowerPC,8248@0/name > PowerPC,8248 > /proc/device-tree/cpus/PowerPC,8248@0/bus-frequency > 0000000 03ef 1480 > /proc/device-tree/cpus/PowerPC,8248@0/clock-frequency > 0000000 0dc4 c7c0 > /proc/device-tree/cpus/PowerPC,8248@0/timebase-frequency > 0000000 00fb c520 > /proc/device-tree/cpus/PowerPC,8248@0/i-cache-size > 0000000 0000 4000 > > > > On 11/29/07, Vitaly Bordug wrote: > > On Wed, 28 Nov 2007 21:06:36 -0700 > > Alan Bennett wrote: > > > > > It comes from uboot. Can you point me in the right direction to make > > > sure its right? > > > PowerPC,8248@0 { > > > device_type = "cpu"; > > > reg = <0>; > > > d-cache-line-size = ; > > > i-cache-line-size = ; > > > d-cache-size = ; > > > i-cache-size = ; > > > timebase-frequency = <0>; > > > clock-frequency = <0>; > > > }; > > > > > if your u-boot is up to date, it will have fdt command, and by > > fdt boardsetup > > fdt print / > > > > inspect what u-boot did. Of course you should have dtb preloaded to memory and > > fdt addr should be said to let u-boot know where dtb resides. > > > > > > > > > > On 11/28/07, Scott Wood wrote: > > > > Alan Bennett wrote: > > > > > I've got a routine that needs to delay for X microseconds, this > > > > > is a must. The command after schedule_timeout must has to wait > > > > > for the HW to complete a task that takes X microseconds. > > > > > > > > > > I would think that one way to do this is with a simple > > > > > schedule_timeout. But in the example below, the time that passes > > > > > from run1() to dontrun() is far less than 3.2 msecs. Infact, > > > > > sometimes its ~ 800 micros according the a analyzer looking at > > > > > points triggered in run1() and donrun(). Could this be a > > > > > configuration problem with the timer/interrupt that generates the > > > > > jiffies? > > > > > > > > Are you sure the timebase frequency is set correctly in the device > > > > tree? > > > > > > > > -Scott > > > > > > > _______________________________________________ > > > Linuxppc-dev mailing list > > > Linuxppc-dev@ozlabs.org > > > https://ozlabs.org/mailman/listinfo/linuxppc-dev > > > > > > -- > > Sincerely, Vitaly > > >