From mboxrd@z Thu Jan 1 00:00:00 1970 From: paul@pwsan.com (Paul Walmsley) Date: Fri, 02 Jul 2010 09:29:10 -0600 Subject: [PATCH 01/20] OMAP3: wait on IDLEST after enabling USBTLL fclk In-Reply-To: <20100702152703.6221.33529.stgit@localhost.localdomain> References: <20100702152703.6221.33529.stgit@localhost.localdomain> Message-ID: <20100702152906.6221.27841.stgit@localhost.localdomain> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org From: Anand Gadiyar We need to wait on the IDLEST bit after the clocks are enabled before attempting to access any register. Currently, the USBTLL i-clock ops uses the clkops_omap2_dflt_wait, while the USBTLL f-clock ops uses clkops_omap2_dflt. If the i-clock is enabled first, the clkops_omap2_dflt_wait is short-circuited as the companion f-clock is not enabled. This can cause a data abort if the IDLEST has not transitioned, and we try to access a USBTLL register. Since the USBTLL i-clock and f-clock could be enabled in any order, this is a bug. Fix it by changing the clkops for the f-clock. Signed-off-by: Anand Gadiyar Signed-off-by: Paul Walmsley --- arch/arm/mach-omap2/clock3xxx_data.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/arch/arm/mach-omap2/clock3xxx_data.c b/arch/arm/mach-omap2/clock3xxx_data.c index 41b155a..c226798 100644 --- a/arch/arm/mach-omap2/clock3xxx_data.c +++ b/arch/arm/mach-omap2/clock3xxx_data.c @@ -1408,7 +1408,7 @@ static struct clk ts_fck = { static struct clk usbtll_fck = { .name = "usbtll_fck", - .ops = &clkops_omap2_dflt, + .ops = &clkops_omap2_dflt_wait, .parent = &dpll5_m2_ck, .enable_reg = OMAP_CM_REGADDR(CORE_MOD, OMAP3430ES2_CM_FCLKEN3), .enable_bit = OMAP3430ES2_EN_USBTLL_SHIFT,