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2016-02-11ARM: 8519/1: ICST: try other dividends than 1Linus Walleij1-0/+1
Since the dawn of time the ICST code has only supported divide by one or hang in an eternal loop. Luckily we were always dividing by one because the reference frequency for the systems using the ICSTs is 24MHz and the [min,max] values for the PLL input if [10,320] MHz for ICST307 and [6,200] for ICST525, so the loop will always terminate immediately without assigning any divisor for the reference frequency. But for the code to make sense, let's insert the missing i++ Reported-by: David Binderman <dcb314@hotmail.com> Cc: stable@vger.kernel.org Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2016-02-08ARM: 8517/1: ICST: avoid arithmetic overflow in icst_hz()Linus Walleij1-2/+6
When trying to set the ICST 307 clock to 25174000 Hz I ran into this arithmetic error: the icst_hz_to_vco() correctly figure out DIVIDE=2, RDW=100 and VDW=99 yielding a frequency of 25174000 Hz out of the VCO. (I replicated the icst_hz() function in a spreadsheet to verify this.) However, when I called icst_hz() on these VCO settings it would instead return 4122709 Hz. This causes an error in the common clock driver for ICST as the common clock framework will call .round_rate() on the clock which will utilize icst_hz_to_vco() followed by icst_hz() suggesting the erroneous frequency, and then the clock gets set to this. The error did not manifest in the old clock framework since this high frequency was only used by the CLCD, which calls clk_set_rate() without first calling clk_round_rate() and since the old clock framework would not call clk_round_rate() before setting the frequency, the correct values propagated into the VCO. After some experimenting I figured out that it was due to a simple arithmetic overflow: the divisor for 24Mhz reference frequency as reference becomes 24000000*2*(99+8)=0x132212400 and the "1" in bit 32 overflows and is lost. But introducing an explicit 64-by-32 bit do_div() and casting the divisor into (u64) we get the right frequency back, and the right frequency gets set. Tested on the ARM Versatile. Cc: stable@vger.kernel.org Cc: linux-clk@vger.kernel.org Cc: Pawel Moll <pawel.moll@arm.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-10-18Update broken web addresses in arch directory.Justin P. Mattock1-1/+1
The patch below updates broken web addresses in the arch directory. Signed-off-by: Justin P. Mattock <justinmattock@gmail.com> Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Cc: Finn Thain <fthain@telegraphics.com.au> Cc: Randy Dunlap <rdunlap@xenotime.net> Reviewed-by: Finn Thain <fthain@telegraphics.com.au> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-05-02ARM: ICST: kill duplicate icst codeRussell King1-0/+100
The only difference between ICST307 and ICST525 are the two arrays for calculating the S parameter; the code is now identical. Merge the two files and kill the duplicated code. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>