From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dinh Nguyen Date: Mon, 14 Jan 2019 09:58:40 -0600 Subject: [U-Boot] [PATCH v1 1/4] arm: socfpga: imply SPL config instead of select In-Reply-To: <8d7142cb-5674-57d2-dce2-a4595b8a5538@gmail.com> 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> <8d7142cb-5674-57d2-dce2-a4595b8a5538@gmail.com> Message-ID: <9bcf5990-df16-b10f-4f61-4f40bdcd5eb0@kernel.org> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Hi Simon, On 1/14/19 9:50 AM, Simon Goldschmidt wrote: > 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... > I added an early reset driver for SoCFPGA that should take care of this. The patch is in v5.0-rc2[1]. Dinh [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/drivers/reset?id=b3ca9888f35fa6919569cf27c929dc0ac49e9716