svn commit: r274669 - head/sys/arm/broadcom/bcm2835

Warner Losh imp at FreeBSD.org
Tue Nov 18 17:07:04 UTC 2014


Author: imp
Date: Tue Nov 18 17:07:02 2014
New Revision: 274669
URL: https://svnweb.freebsd.org/changeset/base/274669

Log:
  These delays aren't needed. Elimate them. They should be on the order
  of a few cycles at most, not 10us. They make it impossible to
  implement half-duplex protocols that are faster than about 1KHz.
  
  Sponsored by: Netflix

Modified:
  head/sys/arm/broadcom/bcm2835/bcm2835_gpio.c

Modified: head/sys/arm/broadcom/bcm2835/bcm2835_gpio.c
==============================================================================
--- head/sys/arm/broadcom/bcm2835/bcm2835_gpio.c	Tue Nov 18 17:06:56 2014	(r274668)
+++ head/sys/arm/broadcom/bcm2835/bcm2835_gpio.c	Tue Nov 18 17:07:02 2014	(r274669)
@@ -238,9 +238,7 @@ bcm_gpio_set_pud(struct bcm_gpio_softc *
 	offset = pin - 32 * bank;
 
 	BCM_GPIO_WRITE(sc, BCM_GPIO_GPPUD(0), state);
-	DELAY(10);
 	BCM_GPIO_WRITE(sc, BCM_GPIO_GPPUDCLK(bank), (1 << offset));
-	DELAY(10);
 	BCM_GPIO_WRITE(sc, BCM_GPIO_GPPUD(0), 0);
 	BCM_GPIO_WRITE(sc, BCM_GPIO_GPPUDCLK(bank), 0);
 }


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