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charset=UTF-8 Content-Transfer-Encoding: 8bit X-Proofpoint-GUID: fxeCmxpTmYhQ299uJOicHB4NYLjuiChp X-Proofpoint-ORIG-GUID: fxeCmxpTmYhQ299uJOicHB4NYLjuiChp X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwNjI2MDEyOSBTYWx0ZWRfX1UL89lUwIcVw VATzzUCfFJgmm2HgcPmrDsU9GPDO3D6uW+TOfBmI9tC5nXBvh4pJCpybUFsq7PKmU4EWiKfsFNN 9pjo8GaJADE7S1m/nq3J/jXqNskrFvvMSx+A2wn8ZHqpZPiSQEc+y5TGzCwUPbOFbjmQ04bkpNE 9GKa52LkuQoTU33AyeCj84/5tBMuTeQIvP8G/tArF2Qx/4i6rgQMoQaAIi8GDKR7C+K5eEgVDS5 ZdFRAuuVUN599F1HEAO7wGRUuf9zgWEznL1OMRNjrLIxoA35ha3nDjVpkAAIxA2jtcm+YiNj9wx N4QfmpKkkDr+icTKedKAU0wEShAcvW9UnT0tFjZ05Njk2BBhgmvYMHuOweIILRK7x3JgkrKR7pp ADpSoChL2f+qVa/LvKSis5sWpWQ0/hHTPIlD15CU13IzcDy8UsKF+EKtYFgqTaK3xBSJ/pO0dFp cZaklvoYwpoPSTVL+cA== X-Authority-Analysis: v=2.4 cv=FPkrAeos c=1 sm=1 tr=0 ts=6a3e9c09 cx=c_pps a=EVbN6Ke/fEF3bsl7X48z0g==:117 a=PRfkaYvzSr8QmIIGAkY2Sg==:17 a=IkcTkHD0fZMA:10 a=FelO9ux0wxsA:10 a=s4-Qcg_JpJYA:10 a=VkNPw1HP01LnGYTKEx00:22 a=u7WPNUs3qKkmUXheDGA7:22 a=3WHJM1ZQz_JShphwDgj5:22 a=EUspDBNiAAAA:8 a=KdbZC8JMYa_JGPUaySMA:9 a=3ZKOabzyN94A:10 a=QEXdDO2ut3YA:10 a=a_PwQJl-kcHnX1M80qC6:22 X-Proofpoint-Spam-Info: AW1haW4tMjYwNjI2MDEyOSBTYWx0ZWRfX4/NU7gaSIrz7 yySZ+Ota6ZqPuNqCywSvefE2IPSu6MnyTfMboLWUberNboXmNfd1xWv6EuP7UnTkcLv8ZiuFnV1 S8QXpXrdigd6QDowdL90/R1FSdhn69U= X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1143,Hydra:6.1.125,FMLib:17.12.100.49 definitions=2026-06-26_03,2026-06-26_01,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 clxscore=1015 priorityscore=1501 malwarescore=0 adultscore=0 bulkscore=0 impostorscore=0 phishscore=0 suspectscore=0 lowpriorityscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2606150000 definitions=main-2606260129 On 6/25/26 11:06 AM, Mukesh Savaliya wrote: > Hi Konrad, sorry for late response. > > On 6/15/2026 5:12 PM, Konrad Dybcio wrote: >> On 6/15/26 6:25 AM, Pengyu Luo wrote: >>> On Mon, Jun 15, 2026 at 5:18 AM Dmitry Baryshkov >>> wrote: >>>> >>>> On Sun, Jun 14, 2026 at 04:34:24PM +0800, Pengyu Luo wrote: >>>>> Some devices (such as gaokun3) do not disable FIFO mode, causing the >>>>> driver to fallback to FIFO mode by default. However, these platforms >>>>> also support GSI mode, which is highly preferred for certain >>>>> peripherals like SPI touchscreens to improve performance. >>>>> >>>>> Introduce the "qcom,force-gsi-mode" device property to hint and force >>>>> the controller into GSI mode during initialization. >>>> >>>> Ideally, this should be decided by the SPI controller based on the >>>> requirements. Another option would be to prefer GSI for all transfers if >>>> it is available, ignoring the FIFO even if it is not disabled. >>>> >>> >>> I have read reviews. Can we check if the compatible >>> "qcom,sm6350-gpi-dma" is in DT? If the gpi dma controller is >>> presented, then we enable GSI mode. >> >> >> This hunk is very odd: >> >> /* >>   * in case of failure to get gpi dma channel, we can still do the >>   * FIFO mode, so fallthrough >>   */ >> dev_warn(mas->dev, "FIFO mode disabled, but couldn't get DMA, fall back to FIFO mode\n"); >> >> In my understanding, GSI DMA mode is always preferable. +Mukesh, do >> you have any insights? >> > GSI mode is preferable but if for some reason it fails, we try to continue with the FIFO mode. Just fallback mechanism. So, would making GSI the default and FIFO the fallback option sound good? Konrad