From mboxrd@z Thu Jan 1 00:00:00 1970 From: Simon Goldschmidt Date: Mon, 14 Jan 2019 16:50:47 +0100 Subject: [U-Boot] [PATCH v1 1/4] arm: socfpga: imply SPL config instead of select In-Reply-To: <00f186a1-7aea-8d46-770d-b5e08f1f92c2@denx.de> References: <20190107211423.10151-1-simon.k.r.goldschmidt@gmail.com> <20190107211423.10151-2-simon.k.r.goldschmidt@gmail.com> <033b301a-612d-3b80-7ecc-04530851c1ec@denx.de> <1dd165cd-2cad-013b-877c-78fe5780f9cf@gmail.com> <00f186a1-7aea-8d46-770d-b5e08f1f92c2@denx.de> Message-ID: <8d7142cb-5674-57d2-dce2-a4595b8a5538@gmail.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Am 11.01.2019 um 23:02 schrieb Marek Vasut: > On 1/11/19 9:39 PM, Simon Goldschmidt wrote: >> Am 07.01.2019 um 23:53 schrieb Marek Vasut: >>> On 1/7/19 10:14 PM, Simon Goldschmidt wrote: >>>> In order to build a smaller SPL, let's imply SPL_DM_RESET and >>>> SPL_WATCHDOG_SUPPORT instead of selecting them, so they can be disabled >>>> via defconfig. >>>> >>>> This also seems to be required to use OF_PLATDATA, as the reset drivers >>>> don't seem to work with it. >>> >>> How do you un-reset IP blocks if you disable the reset controller ? >> >> I found that out just now: there's the function >> 'reset_deassert_peripherals_handoff()' in spl_gen5.c that should >> "De-assert reset for peripherals and bridges based on handoff". However, >> at least for Gen5, it just writes a 0 to rstmgr->permodrst. By doing >> that, it enables *ALL* peripherals on the SoC (except for some DMA >> channels that aren't really used) :-) >> >> I guess that needs some cleaning up as well ;-) > > Yes > >> I think the proper thing to do here would be to remove this function and >> convert all drivers to provide appropriate 'resets' properties in the dts? > > Indeed So I just did that and it works nice for SPL and U-Boot: By adding some "resets" properties the the main dtsi and adding reset bulk code to the cadence_qspi, denali_dt nand and drivers, I can nearly remove the reset code from arch/mach_socfpga. The problem would be that now Linux cannot use peripherals that aren't enabled by U-Boot because it relies on them being enabled. How are such dependencies solved? Because even if I would add reset support in the corresponding Linux drivers, we probably could not bootolder Kernels (e.g. the Debian 9 kernel - v4.9.x) with a new U-Boot... Regards, Simon