Larry Finger <Larry.Finger@xxxxxxxxxxxx> writes:
> On 5/1/24 11:14 AM, Ziyang Huang wrote:
>
>> On 64bit OS, when ab->mem_ce is lower than or 4G far away from ab->mem,
>> u32 is not enough to store the offsets, which makes ath11k_ahb_read32()
>> and ath11k_ahb_write32() access incorrect address and causes Data Abort
>> Exception.
>> Let's use the high bits of offsets to decide where to access, which
>> is
>> similar as ath11k_pci_get_window_start() done. In the future, we can merge
>> these functions for unified regs accessing.
>> Signed-off-by: Ziyang Huang <hzyitc@xxxxxxxxxxx>
>> ---
>> drivers/net/wireless/ath/ath11k/ahb.c | 34 ++++++++++++++++++++-------
>> drivers/net/wireless/ath/ath11k/hal.c | 17 +++++---------
>> drivers/net/wireless/ath/ath11k/hw.c | 14 +++++------
>> drivers/net/wireless/ath/ath11k/hw.h | 7 +++++-
>> 4 files changed, 45 insertions(+), 27 deletions(-)
>> diff --git a/drivers/net/wireless/ath/ath11k/ahb.c
>> b/drivers/net/wireless/ath/ath11k/ahb.c
>> index 7c0a23517949..9e59b4de93a9 100644
>> --- a/drivers/net/wireless/ath/ath11k/ahb.c
>> +++ b/drivers/net/wireless/ath/ath11k/ahb.c
>> @@ -198,12 +198,30 @@ static const struct ath11k_pci_ops ath11k_ahb_pci_ops_wcn6750 = {
>> static inline u32 ath11k_ahb_read32(struct ath11k_base *ab, u32
>> offset)
>> {
>> - return ioread32(ab->mem + offset);
>> + switch (offset & ATH11K_REG_TYPE_MASK) {
>> + case ATH11K_REG_TYPE_NORMAL:
>> + return ioread32(ab->mem + FIELD_GET(ATH11K_REG_OFFSET_MASK, offset));
>> + case ATH11K_REG_TYPE_CE:
>> + return ioread32(ab->mem_ce + FIELD_GET(ATH11K_REG_OFFSET_MASK, offset));
>> + default:
>> + BUG();
>
> Do you really want to crash the system here? A dev_warn() or something
> similar would log the situation. I suspect this case is never taken,
> but a system crash is not a good response if it is.
Correct, BUG() is more or less banned from all wireless code.
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