From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755966AbcEYRKu (ORCPT ); Wed, 25 May 2016 13:10:50 -0400 Received: from mail-pa0-f53.google.com ([209.85.220.53]:34469 "EHLO mail-pa0-f53.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755470AbcEYRKs (ORCPT ); Wed, 25 May 2016 13:10:48 -0400 Date: Wed, 25 May 2016 10:10:43 -0700 From: Bjorn Andersson To: Peter Griffin Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, srinivas.kandagatla@gmail.com, maxime.coquelin@st.com, patrice.chotard@st.com, vinod.koul@intel.com, ohad@wizery.com, arnd@arndb.de, lee.jones@linaro.org, devicetree@vger.kernel.org, dmaengine@vger.kernel.org, linux-remoteproc@vger.kernel.org Subject: Re: [PATCH v4 01/18] remoteproc: st_xp70_rproc: add a xp70 slimcore rproc driver Message-ID: <20160525171043.GT1256@tuxbot> References: <1464192412-16386-1-git-send-email-peter.griffin@linaro.org> <1464192412-16386-3-git-send-email-peter.griffin@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1464192412-16386-3-git-send-email-peter.griffin@linaro.org> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed 25 May 09:06 PDT 2016, Peter Griffin wrote: > XP70 slim core is used as a basis for many IPs in the STi > chipsets such as fdma, display, and demux. To avoid > duplicating the elf loading code in each device driver > an xp70 rproc driver has been created. > I like this approach. [..] > diff --git a/drivers/remoteproc/Kconfig b/drivers/remoteproc/Kconfig [..] > > +config ST_XP70_REMOTEPROC > + tristate "XP70 slim remoteproc support" As this "driver" in itself doesn't do anything I don't think it makes sense to have it user selectable. Please make the "clients" select it instead. > + depends on ARCH_STI > + select REMOTEPROC > + help > + Say y here to support xp70 slim core. > + If unsure say N. > + > endmenu > diff --git a/drivers/remoteproc/Makefile b/drivers/remoteproc/Makefile [..] > +#include > +#include You should be able to drop inclusion of elf.h now. [..] > +static int xp70_clk_get(struct st_xp70_rproc *xp70_rproc, struct device *dev) > +{ > + int clk, err = 0; No need to initialize err. > + > + for (clk = 0; clk < XP70_MAX_CLK; clk++) { > + xp70_rproc->clks[clk] = of_clk_get(dev->of_node, clk); > + if (IS_ERR(xp70_rproc->clks[clk])) { > + err = PTR_ERR(xp70_rproc->clks[clk]); > + if (err == -EPROBE_DEFER) > + goto err_put_clks; > + xp70_rproc->clks[clk] = NULL; > + break; > + } > + } > + > + return 0; > + > +err_put_clks: > + while (--clk >= 0) > + clk_put(xp70_rproc->clks[clk]); > + > + return err; > +} > + [..] > +/** > + * Remoteproc xp70 specific device handlers > + */ > +static int xp70_rproc_start(struct rproc *rproc) > +{ > + struct device *dev = &rproc->dev; > + struct st_xp70_rproc *xp70_rproc = rproc->priv; > + unsigned long hw_id, hw_ver, fw_rev; > + u32 val, ret = 0; ret should be signed and there's no need to initialize it. > + > + ret = xp70_clk_enable(xp70_rproc); > + if (ret) { > + dev_err(dev, "Failed to enable clocks\n"); > + goto err_clk; > + } [..] > + > + dev_dbg(dev, "XP70 started\n"); > + > +err_clk: > + return ret; > +} > + > +static int xp70_rproc_stop(struct rproc *rproc) > +{ > + struct st_xp70_rproc *xp70_rproc = rproc->priv; > + u32 val; > + > + /* mask all (cmd & int) channels */ > + writel_relaxed(0UL, xp70_rproc->peri + XP70_INT_MASK_OFST); > + writel_relaxed(0UL, xp70_rproc->peri + XP70_CMD_MASK_OFST); > + > + /* disable cpu pipeline clock */ > + writel_relaxed(XP70_CLK_GATE_DIS > + , xp70_rproc->slimcore + XP70_CLK_GATE_OFST); > + > + writel_relaxed(!XP70_EN_RUN, xp70_rproc->slimcore + XP70_EN_OFST); Don't you want to ensure ordering of these writes? Perhaps making this last one a writel()? > + > + val = readl_relaxed(xp70_rproc->slimcore + XP70_EN_OFST); > + if (val & XP70_EN_RUN) > + dev_warn(&rproc->dev, "Failed to disable XP70"); > + > + xp70_clk_disable(xp70_rproc); > + > + dev_dbg(&rproc->dev, "xp70 stopped\n"); > + > + return 0; > +} > + > +static void *xp70_rproc_da_to_va(struct rproc *rproc, u64 da, int len) > +{ > + struct st_xp70_rproc *xp70_rproc = rproc->priv; > + void *va = NULL; > + int i; > + > + for (i = 0; i < XP70_MEM_MAX; i++) { > + > + if (da != xp70_rproc->mem[i].bus_addr) > + continue; > + > + va = xp70_rproc->mem[i].cpu_addr; > + break; > + } Please clean up the indentation and drop the extra newline at the beginning in this loop. > + > + dev_dbg(&rproc->dev, "%s: da = 0x%llx len = 0x%x va = 0x%p\n" > + , __func__, da, len, va); > + > + return va; > +} > + > +static struct rproc_ops xp70_rproc_ops = { > + .start = xp70_rproc_start, > + .stop = xp70_rproc_stop, > + .da_to_va = xp70_rproc_da_to_va, > +}; > + > +/** > + * Firmware handler operations: sanity, boot address, load ... > + */ > + > +static struct resource_table empty_rsc_tbl = { > + .ver = 1, > + .num = 0, > +}; I'm looking at making the resource table optional, good to see another vote for that. Looks good for now though. [..] > + > +/** > + * xp70_rproc_alloc - allocate and initialise xp70 rproc Drop one of the two spaces indenting this block and add () after then function name. > + * @pdev: Pointer to the platform_device struct > + * @fw_name: Name of firmware for rproc to use > + * > + * Function for allocating and initialising a xp70 rproc for use by > + * device drivers whose IP is based around the xp70 slim core. It > + * obtains and enables any clocks required by the xp70 core and also > + * ioremaps the various IO. > + * > + * Returns rproc pointer or PTR_ERR() on error. > + */ > + > +struct rproc *xp70_rproc_alloc(struct platform_device *pdev, char *fw_name) > +{ > + struct device *dev = &pdev->dev; > + struct st_xp70_rproc *xp70_rproc; > + struct device_node *np = dev->of_node; > + struct rproc *rproc; > + struct resource *res; > + int err, i; > + const struct rproc_fw_ops *elf_ops; > + > + if (!np || !fw_name) > + return ERR_PTR(-EINVAL); This should, I believe, only ever happen in development. So if you want to keep it to aid developers feel free to throw in a WARN_ON() in the condition. > + > + if (!of_device_is_compatible(np, "st,xp70-rproc")) > + return ERR_PTR(-EINVAL); > + > + rproc = rproc_alloc(dev, np->name, &xp70_rproc_ops, > + fw_name, sizeof(*xp70_rproc)); > + if (!rproc) > + return ERR_PTR(-ENOMEM); > + > + rproc->has_iommu = false; > + > + xp70_rproc = rproc->priv; > + xp70_rproc->rproc = rproc; > + > + /* Get standard ELF ops */ > + elf_ops = rproc_get_elf_ops(); > + > + /* Use some generic elf ops */ > + xp70_rproc_fw_ops.load = elf_ops->load; > + xp70_rproc_fw_ops.sanity_check = elf_ops->sanity_check; > + > + rproc->fw_ops = &xp70_rproc_fw_ops; > + > + /* get imem and dmem */ > + for (i = 0; i < ARRAY_SIZE(mem_names); i++) { > + res = xp70_rproc->mem[i].io_res; > + io_res is NULL here, and res is directly assigned again. So drop this and io_res from the struct. > + res = platform_get_resource_byname > + (pdev, IORESOURCE_MEM, mem_names[i]); > + > + xp70_rproc->mem[i].cpu_addr = devm_ioremap_resource(dev, res); > + if (IS_ERR(xp70_rproc->mem[i].cpu_addr)) { > + dev_err(&pdev->dev, "devm_ioremap_resource failed\n"); > + err = PTR_ERR(xp70_rproc->mem[i].cpu_addr); > + goto err; > + } > + xp70_rproc->mem[i].bus_addr = res->start; > + xp70_rproc->mem[i].size = resource_size(res); > + } > + > + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "slimcore"); > + > + xp70_rproc->slimcore = devm_ioremap_resource(dev, res); > + if (IS_ERR(xp70_rproc->slimcore)) { > + dev_err(&pdev->dev, "devm_ioremap_resource failed for slimcore\n"); > + err = PTR_ERR(xp70_rproc->slimcore); > + goto err; > + } > + > + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "peripherals"); > + > + xp70_rproc->peri = devm_ioremap_resource(dev, res); > + if (IS_ERR(xp70_rproc->peri)) { > + dev_err(&pdev->dev, "devm_ioremap_resource failed for peri\n"); > + err = PTR_ERR(xp70_rproc->peri); > + goto err; > + } > + > + err = xp70_clk_get(xp70_rproc, dev); > + if (err) > + goto err; > + > + /* Register as a remoteproc device */ > + err = rproc_add(rproc); > + if (err) { > + dev_err(dev, "registration of xp70 remoteproc failed\n"); > + goto err; In this case you should also put the clocks. > + } > + > + dev_dbg(dev, "XP70 rproc init successful\n"); > + return rproc; > + > +err: > + rproc_put(rproc); > + return ERR_PTR(err); > +} > +EXPORT_SYMBOL(xp70_rproc_alloc); > + > +/** > + * xp70_rproc_put - put xp70 rproc resources > + * @xp70_rproc: Pointer to the st_xp70_rproc struct > + * > + * Function for calling respective _put() functions on > + * xp70_rproc resources. > + * > + * Returns rproc pointer or PTR_ERR() on error. > + */ > +void xp70_rproc_put(struct st_xp70_rproc *xp70_rproc) > +{ > + int clk; > + > + if (!xp70_rproc) > + return; > + > + rproc_put(xp70_rproc->rproc); > + > + for (clk = 0; clk < XP70_MAX_CLK && xp70_rproc->clks[clk]; clk++) > + clk_put(xp70_rproc->clks[clk]); rproc_put() will free your private data, i.e. xp70_rproc, so you must put your clocks before that. > + > +} > +EXPORT_SYMBOL(xp70_rproc_put); > + > +MODULE_AUTHOR("Peter Griffin"); > +MODULE_DESCRIPTION("STMicroelectronics XP70 rproc driver"); > +MODULE_LICENSE("GPL v2"); > diff --git a/include/linux/remoteproc/st_xp70_rproc.h b/include/linux/remoteproc/st_xp70_rproc.h [..] > + > +#define XP70_MEM_MAX 2 > +#define XP70_MAX_CLK 4 > +#define NAME_SZ 10 NAME_SZ seems unused and would be too generic. > + > +enum { > + DMEM, > + IMEM, These are too generic for a header file. > +}; > + > +/** > + * struct xp70_mem - xp70 internal memory structure > + * @cpu_addr: MPU virtual address of the memory region > + * @bus_addr: Bus address used to access the memory region > + * @dev_addr: Device address from Wakeup M3 view > + * @size: Size of the memory region > + */ > +struct xp70_mem { > + void __iomem *cpu_addr; > + phys_addr_t bus_addr; > + u32 dev_addr; dev_addr is unused. > + size_t size; > + struct resource *io_res; io_res is unused. > +}; > + > +/** > + * struct st_xp70_rproc - XP70 slim core > + * @rproc: rproc handle > + * @pdev: pointer to platform device > + * @mem: xp70 memory information > + * @slimcore: xp70 slimcore regs > + * @peri: xp70 peripheral regs > + * @clks: xp70 clocks > + */ > +struct st_xp70_rproc { > + struct rproc *rproc; > + struct platform_device *pdev; pdev is unused. > + struct xp70_mem mem[XP70_MEM_MAX]; > + void __iomem *slimcore; > + void __iomem *peri; > + struct clk *clks[XP70_MAX_CLK]; > +}; I generally don't like sharing a struct like this between two implementations, but I don't think it's worth working around it in this case. Perhaps you can group the members into a section of "public" and a section of "private" members; with a /* st_xp70_rproc private */ heading the latter? > + > +struct rproc *xp70_rproc_alloc(struct platform_device *pdev, char *fw_name); For consistency I think xp70_rproc_alloc() should return a st_xp70_rproc reference, rather than forcing the clients pull that pointer out of rproc->priv. > +void xp70_rproc_put(struct st_xp70_rproc *xp70_rproc); > + > +#endif Regards, Bjorn