On 14 May 2016 at 18:33, Conrad Meyer <c...@freebsd.org> wrote: > On Sat, May 14, 2016 at 12:52 PM, Adrian Chadd <adr...@freebsd.org> wrote: >> Author: adrian >> Date: Sat May 14 19:52:04 2016 >> New Revision: 299751 >> URL: https://svnweb.freebsd.org/changeset/base/299751 >> >> Log: >> [bwn] migrate sqrt and add another couple of util routines. >> >> ... >> >> +unsigned int >> +bwn_sqrt(struct bwn_mac *mac, unsigned int x) >> +{ >> + /* Table holding (10 * sqrt(x)) for x between 1 and 256. */ >> + static uint8_t sqrt_table[256] = { >> + 10, 14, 17, 20, 22, 24, 26, 28, >> ... >> + }; >> + >> + if (x == 0) >> + return (0); >> + if (x >= 256) { >> + unsigned int tmp; >> + >> + for (tmp = 0; x >= (2 * tmp) + 1; x -= (2 * tmp++) + 1) >> + /* do nothing */ ; >> + return (tmp); > > Does this approximation method have a name?
"whatever the broadcom driver requires". >> + } >> + return (sqrt_table[x - 1] / 10); > > Why do we store the table as 10*sqrt() if we're just going to divide > every entry by ten? no idea, I just shuffled the code around so newer PHY code can use it! -a _______________________________________________ svn-src-head@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"