Date: Sat, 26 Apr 2014 20:27:59 +0000 (UTC) From: Ian Lepore <ian@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r264985 - head/sys/dev/uart Message-ID: <201404262027.s3QKRx8w031866@svn.freebsd.org>
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Author: ian Date: Sat Apr 26 20:27:58 2014 New Revision: 264985 URL: http://svnweb.freebsd.org/changeset/base/264985 Log: Reword a comment block a bit; no functional changes. Modified: head/sys/dev/uart/uart_dev_imx.c Modified: head/sys/dev/uart/uart_dev_imx.c ============================================================================== --- head/sys/dev/uart/uart_dev_imx.c Sat Apr 26 20:27:54 2014 (r264984) +++ head/sys/dev/uart/uart_dev_imx.c Sat Apr 26 20:27:58 2014 (r264985) @@ -131,13 +131,14 @@ imx_uart_init(struct uart_bas *bas, int /* * The hardware has an extremely flexible baud clock: it allows setting * both the numerator and denominator of the divider, as well as a - * separate pre-divider. We simplify that problem by assuming a - * pre-divider and numerator of one because our base clock is so fast we - * can reach virtually any reasonable speed with a simple divisor. The - * numerator value actually includes the 16x over-sampling; the register - * value is the numerator-1, so we have a hard-coded 15. Note that a - * quirk of the hardware requires that both UBIR and UBMR be set back to - * back in order for the change to take effect. + * separate pre-divider. We simplify the problem of coming up with a + * workable pair of numbers by assuming a pre-divider and numerator of + * one because our base clock is so fast we can reach virtually any + * reasonable speed with a simple divisor. The numerator value actually + * includes the 16x over-sampling (so a value of 16 means divide by 1); + * the register value is the numerator-1, so we have a hard-coded 15. + * Note that a quirk of the hardware requires that both UBIR and UBMR be + * set back to back in order for the change to take effect. */ if (baudrate > 0) { baseclk = imx_ccm_uart_hz();
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