On 09/03/2023 11:16, Marc Gonzalez wrote:
> On 06/03/2023 11:24, Marc Gonzalez wrote:
>
>> # cat /sys/bus/sdio/devices/mmc2:0001:1/uevent
>> OF_NAME=wifi
>> OF_FULLNAME=/soc/sd@ffe03000/wifi@1
>> OF_COMPATIBLE_0=brcm,bcm4329-fmac
>> OF_COMPATIBLE_N=1
>> SDIO_CLASS=00
>> SDIO_ID=02D0:AAE7
>> SDIO_REVISION=0.0
>> MODALIAS=sdio:c00v02D0dAAE7
>>
>> NB: 0xaae7 = 43751
>
> I have run into another issue.
>
> The WiFi device (and the mmc2 bus it sits on) don't show up at all
> in the kernel log *unless* I add lots of debug output, such as with
> #define DEBUG in drivers/base/dd.c
>
> I think this points to some kind of race condition?
>
> Neil suggested that maybe the host probes the mmc2 bus "too soon",
> when the WiFi device is still powering up, which makes the entire
> probe fail.
>
> This patch appears to solve the symptom:
>
> diff --git a/drivers/mmc/host/meson-gx-mmc.c b/drivers/mmc/host/meson-gx-mmc.c
> index 6e5ea0213b477..999b3843c0d0b 100644
> --- a/drivers/mmc/host/meson-gx-mmc.c
> +++ b/drivers/mmc/host/meson-gx-mmc.c
> @@ -1400,7 +1400,7 @@ static struct platform_driver meson_mmc_driver = {
> .remove = meson_mmc_remove,
> .driver = {
> .name = DRIVER_NAME,
> - .probe_type = PROBE_PREFER_ASYNCHRONOUS,
> + .probe_type = PROBE_FORCE_SYNCHRONOUS,
> .of_match_table = meson_mmc_of_match,
> },
> };
>
> But this might just be delaying the probe enough for the device
> to become ready?
FWIW, the relevant device tree nodes are:
/* decompiled DTS */
sd@ffe03000 {
compatible = "amlogic,meson-axg-mmc";
reg = <0x0 0xffe03000 0x0 0x800>;
interrupts = <0x0 0xbd 0x4>;
status = "okay";
clocks = <0x2 0x21 0x2 0x3c 0x2 0x2>;
clock-names = "core", "clkin0", "clkin1";
resets = <0x5 0x2c>;
amlogic,dram-access-quirk;
pinctrl-0 = <0x2c>;
pinctrl-1 = <0x2d>;
pinctrl-names = "default", "clk-gate";
#address-cells = <0x1>;
#size-cells = <0x0>;
bus-width = <0x4>;
cap-sd-highspeed;
sd-uhs-sdr50;
max-frequency = <0x5f5e100>;
non-removable;
disable-wp;
keep-power-in-suspend;
mmc-pwrseq = <0x2e>;
vmmc-supply = <0x2b>;
vqmmc-supply = <0x21>;
wifi@1 {
reg = <0x1>;
compatible = "brcm,bcm4329-fmac";
};
};
/* original DTS */
sd_emmc_a: sd@ffe03000 {
compatible = "amlogic,meson-axg-mmc";
reg = <0x0 0xffe03000 0x0 0x800>;
interrupts = <GIC_SPI 189 IRQ_TYPE_LEVEL_HIGH>;
status = "disabled";
clocks = <&clkc CLKID_SD_EMMC_A>,
<&clkc CLKID_SD_EMMC_A_CLK0>,
<&clkc CLKID_FCLK_DIV2>;
clock-names = "core", "clkin0", "clkin1";
resets = <&reset RESET_SD_EMMC_A>;
};
&sd_emmc_a {
status = "okay";
pinctrl-0 = <&sdio_pins>;
pinctrl-1 = <&sdio_clk_gate_pins>;
pinctrl-names = "default", "clk-gate";
#address-cells = <1>;
#size-cells = <0>;
bus-width = <4>;
cap-sd-highspeed;
sd-uhs-sdr50;
max-frequency = <100000000>;
non-removable;
disable-wp;
/* WiFi firmware requires power to be kept while in suspend */
keep-power-in-suspend;
mmc-pwrseq = <&sdio_pwrseq>;
vmmc-supply = <&vddao_3v3>;
vqmmc-supply = <&vddio_ao1v8>;
brcmf: wifi@1 {
reg = <1>;
compatible = "brcm,bcm4329-fmac";
};
};
With an asynchronous probe, meson_mmc_probe() always succeeds,
yet the WiFi card is not detected later on, even if I sleep
1-2 seconds in meson_mmc_probe().
[ 0.879756] YO: meson_mmc_probe: ffe03000.sd
[ 0.914320] YO: meson_mmc_probe: ffe03000.sd ALL OK
[ 1.199170] YO: meson_mmc_probe: ffe07000.mmc
[ 1.232734] YO: meson_mmc_probe: ffe07000.mmc ALL OK
Confused again...
Regards
