Re: [PATCH v2 2/2] bus: mhi: host: pci_generic: Add edl callback to enter EDL

[Qiang Yu <quic_qianyu@quicinc.com>]

On 4/11/2024 10:46 PM, Jeffrey Hugo wrote:
> On 4/10/2024 9:15 PM, Qiang Yu wrote:
>> Add mhi_pci_generic_edl_trigger as edl_trigger for some devices (eg. 
>> SDX65)
>> to enter EDL mode by writing the 0xEDEDEDED cookie to the channel 91
>> doorbell register and forcing an SOC reset afterwards.
>>
>> Signed-off-by: Qiang Yu <quic_qianyu@quicinc.com>
>> ---
>>   drivers/bus/mhi/host/pci_generic.c | 50 
>> ++++++++++++++++++++++++++++++++++++++
>>   1 file changed, 50 insertions(+)
>>
>> diff --git a/drivers/bus/mhi/host/pci_generic.c 
>> b/drivers/bus/mhi/host/pci_generic.c
>> index 51639bf..a529815 100644
>> --- a/drivers/bus/mhi/host/pci_generic.c
>> +++ b/drivers/bus/mhi/host/pci_generic.c
>> @@ -27,12 +27,23 @@
>>   #define PCI_VENDOR_ID_THALES    0x1269
>>   #define PCI_VENDOR_ID_QUECTEL    0x1eac
>>   +#define MHI_EDL_DB            91
>> +#define MHI_EDL_COOKIE            0xEDEDEDED
>> +
>> +/* Device can enter EDL by first setting edl cookie then issuing 
>> inband reset*/
>> +#define MHI_PCI_GENERIC_EDL_TRIGGER    BIT(0)
>> +
>> +#define CHDBOFF            0x18
>
> This is already in drivers/bus/mhi/common.h why duplicate it here?

I only see common.h be included in ep/internal.h host/internal.h and
host/trace.h. So I thought it can only be used by MHI stack. Can we
include common.h in pci_generic.c?
>
>> +#define CHDBOFF_CHDBOFF_MASK 0xFFFFFFFF
>> +#define CHDBOFF_CHDBOFF_SHIFT    0
>> +
>>   /**
>>    * struct mhi_pci_dev_info - MHI PCI device specific information
>>    * @config: MHI controller configuration
>>    * @name: name of the PCI module
>>    * @fw: firmware path (if any)
>>    * @edl: emergency download mode firmware path (if any)
>> + * @edl_trigger: each bit represents a different way to enter EDL
>>    * @bar_num: PCI base address register to use for MHI MMIO register 
>> space
>>    * @dma_data_width: DMA transfer word size (32 or 64 bits)
>>    * @mru_default: default MRU size for MBIM network packets
>> @@ -44,6 +55,7 @@ struct mhi_pci_dev_info {
>>       const char *name;
>>       const char *fw;
>>       const char *edl;
>> +    unsigned int edl_trigger;
>>       unsigned int bar_num;
>>       unsigned int dma_data_width;
>>       unsigned int mru_default;
>> @@ -292,6 +304,7 @@ static const struct mhi_pci_dev_info 
>> mhi_qcom_sdx75_info = {
>>       .name = "qcom-sdx75m",
>>       .fw = "qcom/sdx75m/xbl.elf",
>>       .edl = "qcom/sdx75m/edl.mbn",
>> +    .edl_trigger = MHI_PCI_GENERIC_EDL_TRIGGER,
>>       .config = &modem_qcom_v2_mhiv_config,
>>       .bar_num = MHI_PCI_DEFAULT_BAR_NUM,
>>       .dma_data_width = 32,
>> @@ -302,6 +315,7 @@ static const struct mhi_pci_dev_info 
>> mhi_qcom_sdx65_info = {
>>       .name = "qcom-sdx65m",
>>       .fw = "qcom/sdx65m/xbl.elf",
>>       .edl = "qcom/sdx65m/edl.mbn",
>> +    .edl_trigger = MHI_PCI_GENERIC_EDL_TRIGGER,
>>       .config = &modem_qcom_v1_mhiv_config,
>>       .bar_num = MHI_PCI_DEFAULT_BAR_NUM,
>>       .dma_data_width = 32,
>> @@ -312,6 +326,7 @@ static const struct mhi_pci_dev_info 
>> mhi_qcom_sdx55_info = {
>>       .name = "qcom-sdx55m",
>>       .fw = "qcom/sdx55m/sbl1.mbn",
>>       .edl = "qcom/sdx55m/edl.mbn",
>> +    .edl_trigger = MHI_PCI_GENERIC_EDL_TRIGGER,
>>       .config = &modem_qcom_v1_mhiv_config,
>>       .bar_num = MHI_PCI_DEFAULT_BAR_NUM,
>>       .dma_data_width = 32,
>> @@ -928,6 +943,38 @@ static void health_check(struct timer_list *t)
>>       mod_timer(&mhi_pdev->health_check_timer, jiffies + 
>> HEALTH_CHECK_PERIOD);
>>   }
>>   +static int mhi_pci_generic_edl_trigger(struct mhi_controller 
>> *mhi_cntrl)
>> +{
>> +    int ret;
>> +    u32 val;
>> +    void __iomem *edl_db;
>> +    void __iomem *base = mhi_cntrl->regs;
>
> It looks like this file follows reverse christmas tree, but this 
> function does not. you should fix it.

Will fix it in next version patch.
>
>> +
>> +    ret = mhi_device_get_sync(mhi_cntrl->mhi_dev);
>> +    if (ret) {
>> +        dev_err(mhi_cntrl->cntrl_dev, "Wake up device fail before 
>> trigger EDL\n");
>> +        return ret;
>> +    }
>> +
>> +    pm_wakeup_event(&mhi_cntrl->mhi_dev->dev, 0);
>> +    mhi_cntrl->runtime_get(mhi_cntrl);
>> +
>> +    mhi_cntrl->read_reg(mhi_cntrl, base + CHDBOFF, &val);
>> +    val = (val & CHDBOFF_CHDBOFF_MASK) >> CHDBOFF_CHDBOFF_SHIFT;
>> +
>> +    edl_db = base + val + (8 * MHI_EDL_DB);
>> +
>> +    mhi_cntrl->write_reg(mhi_cntrl, edl_db + 4, 
>> upper_32_bits(MHI_EDL_COOKIE));
>> +    mhi_cntrl->write_reg(mhi_cntrl, edl_db, 
>> lower_32_bits(MHI_EDL_COOKIE));
>> +
>> +    mhi_soc_reset(mhi_cntrl);
>> +
>> +    mhi_cntrl->runtime_put(mhi_cntrl);
>> +    mhi_device_put(mhi_cntrl->mhi_dev);
>> +
>> +    return 0;
>> +}
>> +
>>   static int mhi_pci_probe(struct pci_dev *pdev, const struct 
>> pci_device_id *id)
>>   {
>>       const struct mhi_pci_dev_info *info = (struct mhi_pci_dev_info 
>> *) id->driver_data;
>> @@ -962,6 +1009,9 @@ static int mhi_pci_probe(struct pci_dev *pdev, 
>> const struct pci_device_id *id)
>>       mhi_cntrl->runtime_put = mhi_pci_runtime_put;
>>       mhi_cntrl->mru = info->mru_default;
>>   +    if (info->edl_trigger & MHI_PCI_GENERIC_EDL_TRIGGER)
>> +        mhi_cntrl->edl_trigger = mhi_pci_generic_edl_trigger;
>> +
>>       if (info->sideband_wake) {
>>           mhi_cntrl->wake_get = mhi_pci_wake_get_nop;
>>           mhi_cntrl->wake_put = mhi_pci_wake_put_nop;
>