| Message ID | 1585917979-17306-1-git-send-email-bmeng.cn@gmail.com |
|---|---|
| State | New |
| Headers | show |
| Series | [v2] serial: ns16550: Fix ordering of getting base address | expand |
Hi Bin, -----"Bin Meng" <bmeng.cn at gmail.com> schrieb: ----- >Betreff: [PATCH v2] serial: ns16550: Fix ordering of getting base >address > >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. > >Fixes: 720f9e1fdb0c9 ("serial: ns16550: Move PCI access from >ofdata_to_platdata() to probe()") >Reported-by: Andy Shevchenko <andriy.shevchenko at linux.intel.com> >Signed-off-by: Bin Meng <bmeng.cn at gmail.com> >Tested-by: Andy Shevchenko <andriy.shevchenko at linux.intel.com> >Reviewed-by: Wolfgang Wallner <wolfgang.wallner at br-automation.com> >Tested-by: Wolfgang Wallner <wolfgang.wallner at br-automation.com> > >--- > >Changes in v2: >- not to break Fixes, etc to two or more lines in the commit message >- add the same CONFIG_SYS_NS16550_PORT_MAPPED ifdefs in the PCI case > > drivers/serial/ns16550.c | 53 >++++++++++++++++++++++++------------------------ > 1 file changed, 27 insertions(+), 26 deletions(-) I have also tested v2, just to be sure. Works as expected. regards, Wolfgang
On Fri, Apr 03, 2020 at 05:46:19AM -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. > > Fixes: 720f9e1fdb0c9 ("serial: ns16550: Move PCI access from ofdata_to_platdata() to probe()") > Reported-by: Andy Shevchenko <andriy.shevchenko at linux.intel.com> > Signed-off-by: Bin Meng <bmeng.cn at gmail.com> > Tested-by: Andy Shevchenko <andriy.shevchenko at linux.intel.com> > Reviewed-by: Wolfgang Wallner <wolfgang.wallner at br-automation.com> > Tested-by: Wolfgang Wallner <wolfgang.wallner at br-automation.com> ... > - 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; (1) for below. ... > + addr = devfdt_get_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 And now is the question why we can't use above as a helper in both cases (either with check for address correctness or without)? > + } ... > + 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; > + } Something like addr = dev_read_addr(dev); ret = ns16550_assign_base(addr, plat); if (ret && !device_is_on_pci_bus(...)) return ret;
diff --git a/drivers/serial/ns16550.c b/drivers/serial/ns16550.c index c1b303f..cb464a5 100644 --- a/drivers/serial/ns16550.c +++ b/drivers/serial/ns16550.c @@ -479,39 +479,28 @@ 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; + /* + * 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; +#ifdef CONFIG_SYS_NS16550_PORT_MAPPED + plat->base = addr; +#else + plat->base = (unsigned long)map_physmem(addr, 0, MAP_NOCACHE); #endif + } ret = reset_get_bulk(dev, &reset_bulk); if (!ret) @@ -535,9 +524,21 @@ 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);
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. Fixes: 720f9e1fdb0c9 ("serial: ns16550: Move PCI access from ofdata_to_platdata() to probe()") Reported-by: Andy Shevchenko <andriy.shevchenko at linux.intel.com> Signed-off-by: Bin Meng <bmeng.cn at gmail.com> Tested-by: Andy Shevchenko <andriy.shevchenko at linux.intel.com> Reviewed-by: Wolfgang Wallner <wolfgang.wallner at br-automation.com> Tested-by: Wolfgang Wallner <wolfgang.wallner at br-automation.com> --- Changes in v2: - not to break Fixes, etc to two or more lines in the commit message - add the same CONFIG_SYS_NS16550_PORT_MAPPED ifdefs in the PCI case drivers/serial/ns16550.c | 53 ++++++++++++++++++++++++------------------------ 1 file changed, 27 insertions(+), 26 deletions(-)