| Message ID | 20230203104822.361415-1-equu@openmail.cc |
|---|---|
| Headers | show |
| Series | PCI: of: Load extra data only from compatible DT nodes | expand |
On Fri, Feb 3, 2023 at 4:48 AM <equu@openmail.cc> wrote: > > From: Edward Chow <equu@openmail.cc> > > ath10k might also be sensitive to the issue reported on > https://github.com/openwrt/openwrt/pull/11345 , loading calibration > data from a device tree node declared incompatible. > > ath10k will first check whether the device tree node is compatible > with it, using the functionality introduced with the first patch of > this series, ("PCI: of: Match pci devices or drivers against OF DT > nodes") and only proceed loading calibration data from compatible node. > > Signed-off-by: Edward Chow <equu@openmail.cc> > Reported-by: kernel test robot <lkp@intel.com> > --- > drivers/net/wireless/ath/ath10k/core.c | 30 ++++++++++++++++++++++++++ > drivers/net/wireless/ath/ath10k/pci.c | 2 +- > drivers/net/wireless/ath/ath10k/pci.h | 2 ++ > 3 files changed, 33 insertions(+), 1 deletion(-) > > diff --git a/drivers/net/wireless/ath/ath10k/core.c b/drivers/net/wireless/ath/ath10k/core.c > index 5eb131ab916f..a776b06f49b5 100644 > --- a/drivers/net/wireless/ath/ath10k/core.c > +++ b/drivers/net/wireless/ath/ath10k/core.c > @@ -13,6 +13,8 @@ > #include <linux/ctype.h> > #include <linux/pm_qos.h> > #include <linux/nvmem-consumer.h> > +#include <linux/of_pci.h> > +#include <linux/pci.h> > #include <asm/byteorder.h> > > #include "core.h" > @@ -26,6 +28,7 @@ > #include "testmode.h" > #include "wmi-ops.h" > #include "coredump.h" > +#include "pci.h" > > unsigned int ath10k_debug_mask; > EXPORT_SYMBOL(ath10k_debug_mask); > @@ -1958,6 +1961,33 @@ static int ath10k_download_cal_nvmem(struct ath10k *ar, const char *cell_name) > size_t len; > int ret; > > + /* devm_nvmem_cell_get() will get a cell first from the OF > + * DT node representing the given device with nvmem-cell-name > + * "calibration", and from the global lookup table as a fallback, > + * and an ath10k device could be either a pci one or a platform one. > + * > + * If the OF DT node is not compatible with the real device, the > + * calibration data got from the node should not be applied. > + * > + * dev_is_pci(ar->dev) && ( no OF node || caldata not from node > + * || not compatible ) -> do not use caldata . > + * > + * !dev_is_pci(ar->dev) -> always use caldata . > + * > + * The judgement for compatibility differs with ath9k for many > + * DT using "qcom,ath10k" as compatibility string. > + */ > + if (dev_is_pci(ar->dev) && > + (!ar->dev->of_node || > + (of_property_match_string(ar->dev->of_node, > + "nvmem-cell-names", > + cell_name) < 0) || > + !of_device_is_compatible(ar->dev->of_node, > + "qcom,ath10k") || > + !of_pci_node_match_driver(ar->dev->of_node, > + &ath10k_pci_driver))) > + return -ENOENT; I think this can be done a bit cleaner and like other drivers. I see 2 options. The first way is use VID/PID compatible strings and don't set the of_node pointer if there is a mismatch. If you must use "qcom,ath10k" (and 9k) only, then we should make of_device_get_match_data() work on PCI drivers. This should just require adding of_match_table ptr and it needs a data struct with a flag saying use cal data or not. Upon further thought, why can't you decide all this just on PCI VID/PID? The giant switch statement in ath10k_pci_probe() could all just be struct of driver_data from the PCI match table. Rob
On Fri, Feb 3, 2023 at 11:15 AM <equu@openmail.cc> wrote: > > > I think this can be done a bit cleaner and like other drivers. I see 2 options. > > The first way is use VID/PID compatible strings and don't set the > > of_node pointer if there is a mismatch. > Where should I do this? In pci_set_of_node() from drivers/pci/of.c? Off the top of my head, I think so. > > Upon further thought, why can't you decide all this just on PCI > > VID/PID? The giant switch statement in ath10k_pci_probe() could all > > just be struct of driver_data from the PCI match table. > > I cannot decide all this just on PCI VID/PID because PCI VID/PID cannot tell whether calibration data are stored in the device (like most expansion cards) or not (for example, in an NVRAM cell referenced by the device tree). > For a given VID/PID, you could have calibration data in DT that you want to ignore sometimes and not other times (because the compatible is wrong)? Rob
> >>> Upon further thought, why can't you decide all this just on PCI >>> VID/PID? The giant switch statement in ath10k_pci_probe() could all >>> just be struct of driver_data from the PCI match table. >> I cannot decide all this just on PCI VID/PID because PCI VID/PID cannot tell whether calibration data are stored in the device (like most expansion cards) or not (for example, in an NVRAM cell referenced by the device tree). >> > For a given VID/PID, you could have calibration data in DT that you > want to ignore sometimes and not other times (because the compatible > is wrong)? Some devices will change their VID/PID after applied with calibration data (e.g. AR922X will do 168c:ff1d -> 168c:0029), but most device trees only record their post-calibration VID/PID in their compatibility string. Should we match such device against their pre-calibration VID/PID only, and break all current device trees for them? I think we could add these pre-calibration VID/PIDs to the ID-list of the PCI driver, but had better match compatibility strings against drivers, not devices.