From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andy Shevchenko Date: Fri, 3 Apr 2020 13:05:56 +0300 Subject: [PATCH] serial: ns16550: Fix ordering of getting base address In-Reply-To: <1585907888-12554-1-git-send-email-bmeng.cn@gmail.com> References: <1585907888-12554-1-git-send-email-bmeng.cn@gmail.com> Message-ID: <20200403100556.GM1922688@smile.fi.intel.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de On Fri, Apr 03, 2020 at 02:58:08AM -0700, Bin Meng wrote: > Currently the driver gets ns16550 base address in the driver > probe() routine, which may potentially break any ns16550 wrapper > driver that does additional initialization before calling > ns16550_serial_probe(). > > Things are complicated that we need consider ns16550 devices on > both simple-bus and PCI bus. To fix the issue we move the base > address assignment for simple-bus ns16550 device back to the > ofdata_to_platdata(), and assign base address for PCI ns16550 > device in ns16550_serial_probe(). > > This is still not perfect. Ideally if any PCI bus based ns16550 > wrapper driver tries to access plat->base before calling probe(), > it is subject to break. Thank you. I have tested it and it fixes my case. Tested-by: Andy Shevchenko > Fixes: 720f9e1fdb0c9 ("serial: ns16550: Move PCI access from > ofdata_to_platdata() to probe()") I believe this should be one line. > Reported-by: Andy Shevchenko > Signed-off-by: Bin Meng > > --- > > drivers/serial/ns16550.c | 51 +++++++++++++++++++++++------------------------- > 1 file changed, 24 insertions(+), 27 deletions(-) > > diff --git a/drivers/serial/ns16550.c b/drivers/serial/ns16550.c > index c1b303f..5e3cd1c 100644 > --- a/drivers/serial/ns16550.c > +++ b/drivers/serial/ns16550.c > @@ -479,39 +479,24 @@ static int ns16550_serial_getinfo(struct udevice *dev, > return 0; > } > > -#if CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA) > -static int ns1655_serial_set_base_addr(struct udevice *dev) > -{ > - fdt_addr_t addr; > - struct ns16550_platdata *plat; > - > - plat = dev_get_platdata(dev); > - > - addr = dev_read_addr_pci(dev); > - if (addr == FDT_ADDR_T_NONE) > - return -EINVAL; > - > -#ifdef CONFIG_SYS_NS16550_PORT_MAPPED > - plat->base = addr; > -#else > - plat->base = (unsigned long)map_physmem(addr, 0, MAP_NOCACHE); > -#endif > - > - return 0; > -} > -#endif > - > int ns16550_serial_probe(struct udevice *dev) > { > + struct ns16550_platdata *plat = dev->platdata; > struct NS16550 *const com_port = dev_get_priv(dev); > struct reset_ctl_bulk reset_bulk; > + fdt_addr_t addr; > int ret; > > -#if CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA) > - ret = ns1655_serial_set_base_addr(dev); > - if (ret) > - return ret; > -#endif > + /* > + * If we are on PCI bus, either directly attached to a PCI root port, > + * or via a PCI bridge, assign platdata->base before probing hardware. > + */ > + if (device_is_on_pci_bus(dev)) { > + addr = devfdt_get_addr_pci(dev); > + if (addr == FDT_ADDR_T_NONE) > + return -EINVAL; > + plat->base = addr; > + } > > ret = reset_get_bulk(dev, &reset_bulk); > if (!ret) > @@ -535,9 +520,21 @@ int ns16550_serial_ofdata_to_platdata(struct udevice *dev) > { > struct ns16550_platdata *plat = dev->platdata; > const u32 port_type = dev_get_driver_data(dev); > + fdt_addr_t addr; > struct clk clk; > int err; > > + addr = dev_read_addr(dev); > + if (addr != FDT_ADDR_T_NONE) { > +#ifdef CONFIG_SYS_NS16550_PORT_MAPPED > + plat->base = addr; > +#else > + plat->base = (unsigned long)map_physmem(addr, 0, MAP_NOCACHE); > +#endif > + } else if (!device_is_on_pci_bus(dev)) { > + return -EINVAL; > + } > + > plat->reg_offset = dev_read_u32_default(dev, "reg-offset", 0); > plat->reg_shift = dev_read_u32_default(dev, "reg-shift", 0); > plat->reg_width = dev_read_u32_default(dev, "reg-io-width", 1); > -- > 2.7.4 > -- With Best Regards, Andy Shevchenko