Re: [PATCH] wifi: brcmfmac: handle missing D3 ACK on BCM4377 T2 Macs

[Aditya Garg]

On 19/09/26 3:00 am, Andre Eikmeyer wrote:
> BCM4377 on the affected T2 Macs does not acknowledge HOST_D3_INFORM.
> The current PCIe suspend callback treats this as fatal and aborts system
> suspend.
> 
> On the affected PCI and DMI combinations, mask the mailbox interrupt,
> preserve the bus-down state, and let generic PCI/ACPI suspend proceed. On
> resume the existing recovery path tears down and probes the device again
> instead of relying on a D0 mailbox transaction.
> 
> Tested-on: MacBookAir9,1, MacBookPro15,4, MacBookPro16,3
> Signed-off-by: Andre Eikmeyer <dev@deq.rocks>
> ---
>  drivers/net/wireless/broadcom/brcm80211/brcmfmac/pcie.c | 42 ++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 42 insertions(+)
> 
> diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/pcie.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/pcie.c
> index 55f4d7b..57bbac1 100644
> --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/pcie.c
> +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/pcie.c
> @@ -9,6 +9,7 @@
>  #include <linux/pci.h>
>  #include <linux/vmalloc.h>
>  #include <linux/delay.h>
> +#include <linux/dmi.h>
>  #include <linux/interrupt.h>
>  #include <linux/bcma/bcma.h>
>  #include <linux/sched.h>
> @@ -49,6 +50,40 @@ enum brcmf_pcie_state {
>  	BRCMFMAC_PCIE_STATE_UP
>  };
>  
> +/*
> + * BCM4377 on these T2 Macs never acknowledges HOST_D3_INFORM. The platform
> + * can nevertheless enter and leave system suspend if the PCIe mailbox
> + * interrupt is masked and resume takes the existing cold-reprobe path.
> + */
> +static const struct dmi_system_id brcmf_pcie_no_d3_ack_quirk[] = {
> +	{
> +		.matches = {
> +			DMI_EXACT_MATCH(DMI_BOARD_VENDOR, "Apple Inc."),
> +			DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "MacBookAir9,1"),
> +		},
> +	},
> +	{
> +		.matches = {
> +			DMI_EXACT_MATCH(DMI_BOARD_VENDOR, "Apple Inc."),
> +			DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "MacBookPro15,4"),
> +		},
> +	},
> +	{
> +		.matches = {
> +			DMI_EXACT_MATCH(DMI_BOARD_VENDOR, "Apple Inc."),
> +			DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "MacBookPro16,3"),
> +		},
> +	},
> +	{}
> +};
> +

The BCM4377 is Apple exclusive and present only on these three Macs. No other Mac, or PC of some other brand uses this. So the DMI check isn't needed.