From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sricharan R Date: Tue, 2 Apr 2013 15:02:21 +0530 Subject: [U-Boot] Potential issue with recent OMAP PRCM struct unification In-Reply-To: References: Message-ID: <515AA5A5.7090607@ti.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Hi Mike Cashwell, On Monday 01 April 2013 09:12 PM, Michael Cashwell wrote: > Greetings, > > I think or something related to it has confused OMAP4 clock init. I haven't entirely unraveled the onion but wanted to ping the list to see if this is known or I'm off in the weeds. > > Using u-boot master at commit a268170 in DEBUG mode the SPL says (in part): > > Enable clock module - 4a008e20 > Enable clock module - 4a008e28 > Enable clock module - 4a008e40 << later builds omit > Enable clock module - 4a009338 << these two clocks > Enable clock module - 4a004528 > Enable clock module - 4a004530 > Enable clock module - 4a004538 > > That build works. But by commit 417c558 the 2 clocks noted are omitted and the later call to get_ram_size() hangs. > > In tracing this I found that the prcm structure initializes one field (cm_l3instr_intrconn_wp1_clkct) but then enable_non_essential_clocks() passes an array populated using a different field (cm_l3instr_intrconn_wp1_clkctrl) to do_enable_clocks(). That latter uninitialized field is zero which terminates that clock init array and results in the two clock omissions above. > > Searching for this and leaving out omap5 for clarity I see: > > cashwell.ubuntu:u-boot$ rgrep cm_l3instr_intrconn_wp1_clkct | grep -v omap5 > ./arch/arm/cpu/armv7/omap4/prcm-regs.c: .cm_l3instr_intrconn_wp1_clkct = 0x4a008e40, > ./arch/arm/cpu/armv7/omap4/hw_data.c: (*prcm)->cm_l3instr_intrconn_wp1_clkctrl, > ./arch/arm/include/asm/omap_common.h: u32 cm_l3instr_intrconn_wp1_clkctrl; > ./arch/arm/include/asm/omap_common.h: u32 cm_l3instr_intrconn_wp1_clkct; > > On first blush, it looks like having both cm_l3instr_intrconn_wp1_clkct and cm_l3instr_intrconn_wp1_clkctrl is a mistake. > > If that's true can anyone say which should be eliminated and whether or not the order of fields in struct prcm_regs matters? > First, on which board are you testing ?. I tested the mainline on my 4460 ES1.1 PANDA and it booted. Also why are you enabling the non-essential clocks ? Now enabling non-essential clocks is deprecated and they are **not** by enabled by default. As you said the unnecessary entry in omap_common.h should be removed and typo in prcm-regs.c I can correct this, but does correcting this gets you working again ? Enabling these two clocks should have nothing to do with boot. Regards, Sricharan