Date: Sun, 20 Oct 2013 17:25:24 +0200 From: Steven Lawrance <stl@koffein.net> To: freebsd-arm <freebsd-arm@freebsd.org> Subject: pl011 UART driver (as used on Raspberry Pi) baud rate divisor Message-ID: <1382282023-sup-4600@luwak.koffein.net>
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--=-1382282724-191894-1322-3059-1-= Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Hi all, attached is a small patch to calculate the baud rate divisor for the pl011 UART. The existing code used hardcoded values which work for a UARTCLK frequency of 3Mhz and a baud rate of 115200. If my calculations are correct, the same values should still end up being set on the RPI but this patch allows it to work on an i.MX233 with a fixed 24MHz clock frequency and it obeys the values in the FDT. Is someone able to test it on the Raspberry Pi? cheers, -- Steven Lawrance stl@koffein.net --=-1382282724-191894-1322-3059-1-= Content-Disposition: attachment; filename="pl011_baudrate.patch" Content-Type: application/octet-stream; name="pl011_baudrate.patch" Content-Transfer-Encoding: base64 SW5kZXg6IHN5cy9kZXYvdWFydC91YXJ0X2Rldl9wbDAxMS5jCj09PT09PT09 PT09PT09PT09PT09PT09PT09PT09PT09PT09PT09PT09PT09PT09PT09PT09 PT09PT09PT09PT09PT0KLS0tIHN5cy9kZXYvdWFydC91YXJ0X2Rldl9wbDAx MS5jCShyZXZpc2lvbiAyNTY3NzkpCisrKyBzeXMvZGV2L3VhcnQvdWFydF9k ZXZfcGwwMTEuYwkoYXJiZXRza29waWEpCkBAIC0xNDcsOSArMTQ3LDYgQEAK IAkJYnJlYWs7CiAJfQogCi0JLyogVE9ETzogQ2FsY3VsYXRlIGRpdmlzb3Jz ICovCi0JYmF1ZCA9ICgweDEgPDwgMTYpIHwgMHgyODsKLQogCWlmIChzdG9w Yml0cyA9PSAyKQogCQlsaW5lIHw9IExDUl9IX1NUUDI7CiAJZWxzZQpAQCAt MTY0LDggKzE2MSwxMSBAQAogCWxpbmUgJj0gIH5MQ1JfSF9GRU47CiAJY3Ry bCB8PSAoQ1JfUlhFIHwgQ1JfVFhFIHwgQ1JfVUFSVEVOKTsKIAotCV9fdWFy dF9zZXRyZWcoYmFzLCBVQVJUX0lCUkQsICgodWludDMyX3QpKGJhdWQgPj4g MTYpKSAmIElCUkRfQkRJVklOVCk7Ci0JX191YXJ0X3NldHJlZyhiYXMsIFVB UlRfRkJSRCwgKHVpbnQzMl90KShiYXVkKSAmIEZCUkRfQkRJVkZSQUMpOwor CWlmIChiYXMtPnJjbGsgIT0gMCAmJiBiYXVkcmF0ZSAhPSAwKSB7CisJCWJh dWQgPSBiYXMtPnJjbGsgKiA0IC8gYmF1ZHJhdGU7CisJCV9fdWFydF9zZXRy ZWcoYmFzLCBVQVJUX0lCUkQsICgodWludDMyX3QpKGJhdWQgPj4gNikpICYg SUJSRF9CRElWSU5UKTsKKwkJX191YXJ0X3NldHJlZyhiYXMsIFVBUlRfRkJS RCwgKHVpbnQzMl90KShiYXVkICYgMHgzRikgJiBGQlJEX0JESVZGUkFDKTsK Kwl9CiAKIAkvKiBBZGQgY29uZmlnLiB0byBsaW5lIGJlZm9yZSByZWVuYWJs aW5nIFVBUlQgKi8KIAlfX3VhcnRfc2V0cmVnKGJhcywgVUFSVF9MQ1JfSCwg KF9fdWFydF9nZXRyZWcoYmFzLCBVQVJUX0xDUl9IKSAmCg== --=-1382282724-191894-1322-3059-1-=--
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