From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jingoo Han Subject: Re: [PATCH V4 1/3] pci: Add PCIe driver for Samsung Exynos Date: Thu, 20 Jun 2013 20:36:01 +0900 Message-ID: <00d901ce6daa$56ffb6b0$04ff2410$@samsung.com> References: <003601ce6756$444e8cd0$cceba670$@samsung.com> <2061566.hRLrhtBK6z@wuerfel> <000901ce6838$8b514720$a1f3d560$@samsung.com> <28355406.ThqqvnG0Yj@wuerfel> <51C2D260.6000303@st.com> <00d701ce6da5$10216ae0$306440a0$@samsung.com> <51C2E6E5.1050001@st.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Return-path: In-reply-to: <51C2E6E5.1050001@st.com> Content-language: ko Sender: linux-samsung-soc-owner@vger.kernel.org To: 'Pratyush Anand' , 'Arnd Bergmann' , 'Mohit KUMAR' Cc: 'Kukjin Kim' , 'Bjorn Helgaas' , linux-samsung-soc@vger.kernel.org, linux-pci@vger.kernel.org, devicetree-discuss@lists.ozlabs.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, 'Grant Likely' , 'Andrew Murray' , 'Thomas Petazzoni' , 'Thierry Reding' , 'Jason Gunthorpe' , 'Surendranath Gurivireddy Balla' , 'Siva Reddy Kallam' , 'Thomas Abraham' , Jingoo Han List-Id: devicetree@vger.kernel.org On Thursday, June 20, 2013 8:26 PM, Pratyush Anand wrote: > On 6/20/2013 4:28 PM, Jingoo Han wrote: > > On Thursday, June 20, 2013 6:59 PM, Pratyush Anand wrote: > >> On 6/13/2013 7:48 PM, Arnd Bergmann wrote: > >>> On Thursday 13 June 2013 22:18:50 Jingoo Han wrote: > >>>>> On Wednesday, June 12, 2013 8:23 PM, Arnd Bergmann wrote: > >>>>>>> On Wednesday 12 June 2013 19:19:05 Jingoo Han wrote: > >>>>>>>>> + > >>>>>>>>> +/* synopsis specific PCIE configuration registers*/ > >>>>>>>>> +#define PCIE_PORT_LINK_CONTROL 0x710 > >>>>>>>>> +#define PORT_LINK_MODE_MASK (0x3f << 16) > >>>>>>>>> +#define PORT_LINK_MODE_4_LANES (0x7 << 16) > >>>>>>> > >>>>>>> Do you mean this is a "Synopsys" designware part? In that case it > >>>>>>> should really not be called "exynos-pcie" but "designware-pcie" > >>>>>>> and you should make sure that the driver makes no assumptions about > >>>>>>> the platform. A lot of other platforms also use designware > >>>>>>> parts and should be able to reuse this driver. > >>>>> > >>>>> Sorry, I don't think so. > >>>>> Only core block is a "Synopsys" designware part IP block, > >>>>> other parts are Exynos-specific. > >>>>> So, it is hard to share with other PCIe IPs using synopsis core. > >>> Just call it synopsys anyway and put a comment in to explain this. > >>> That should be enough for the next person with a synopsys PCI core > >>> to reuse your code and split out the exynos specific parts into a > >>> separate file. > >>> > >> > >> I agree to Arnd that this patch should be split. I had worked in past > >> with SPEAr PCIe which also had designware PCIe IP. I see some code which > >> will fit both in SPEAr as well as in exynos. Unfortunately, I was not > >> able to get SPEAr driver pushed to mainline, as I moved to some other > >> project and got heavily occupied. > > > > Oh, I see. > > > > How about this? > > At the next PATCH v7, I will change the file name from 'pci-exynos.c' > > to 'pci-designware.c', as Arnd mentioned. > > > > Then, when Spear or other platform using designware is submitted, > > this 'pci-designware.c' will be split to two separate files such as > > 'pci-designware.c' and 'pci-exynos.c'. > > > > For me it's OK. Let it go to mainline as Arnd mentioned. > Please keep Mohit in mail chain, who might have some bandwidth to > further add and follow up for SPEAr on top of your patches. Dear Pratyush Anand, Thank you for accepting the suggestion. :) OK, I will keep Mohit in main chain. Best regards, Jingoo Han > > Regards > Pratyush > > > > > Best regards, > > Jingoo Han > > > >> > >> Last patch is here: > >> > >> https://patchwork.kernel.org/patch/1661441/ > >> > >> Infact, these functions should be common to all arm platforms. > >> > >> sys_to_pcie > >> cfg_read > >> cfg_write > >> > >> Following functions should be common to all designware based driver (at > >> least they are same in SPEAr) > >> > >> exynos_pcie_prog_viewport_cfg0 > >> exynos_pcie_prog_viewport_cfg1 > >> exynos_pcie_rd_other_conf > >> exynos_pcie_wr_other_conf > >> exynos_pcie_setup > >> exynos_pcie_valid_config > >> exynos_pcie_rd_conf > >> exynos_pcie_wd_conf > >> exynos_pcie_scan_bus > >> exynos_pcie_map_irq > >> add_pcie_port (after a bit of generalization) > >> exynos_pcie_probe > >> exynos_pcie_remove > >> > >> > >> > >> Following should be specific to exynos: > >> > >> exynos_pcie_rd_own_conf > >> exynos_pcie_wr_own_conf > >> exynos_pcie_link_up > >> exynos_pcie_setup_rc > >> exynos_pcie_assert_core_reset > >> exynos_pcie_deassert_core_reset > >> exynos_pcie_assert_phy_reset > >> exynos_pcie_deassert_phy_reset > >> exynos_pcie_init_phy > >> exynos_pcie_assert_reset > >> exynos_pcie_establish_link > >> exynos_pcie_host_init > >> > >> > >> > >> struct pcie_port_info and struct pcie_port can also be standardized. > >> > >> Regards > >> Pratyush > > > > . > >