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Wysocki" , Pavel Machek , Len Brown , Catalin Marinas , Mark Rutland , Lorenzo Pieralisi , Will Deacon , linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, linux-arm-kernel@lists.infradead.org References: <20260703-disable_boot_cpu_offline-v2-1-782d16ff58c3@oss.qualcomm.com> <20260703-competent-adaptable-coot-f8daaf@sudeepholla> Content-Language: en-US From: Daniel Lezcano In-Reply-To: <20260703-competent-adaptable-coot-f8daaf@sudeepholla> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Proofpoint-ORIG-GUID: 9DaKEXmT2M6n7MzqUaeDklZbuGpnqRiz X-Proofpoint-Spam-Info: AW1haW4tMjYwNzA0MDA2MyBTYWx0ZWRfX93fS9RcPPkDq sWME1StI+33nq0bsW+zciHRl8PgA2Q5Hi/gwTLEH11K3HBDmBaaHR5tjCz/5/XQsUfwg5ogWP96 5hOdjozBoYKnGsWj6jn3Yrs66J1ViDI= X-Authority-Analysis: v=2.4 cv=Z4Tc2nRA c=1 sm=1 tr=0 ts=6a48aba0 cx=c_pps a=qKBjSQ1v91RyAK45QCPf5w==:117 a=/bviTfK1dmy+WGcHzWQ0gg==:17 a=IkcTkHD0fZMA:10 a=RAioF0-LDSMA:10 a=s4-Qcg_JpJYA:10 a=VkNPw1HP01LnGYTKEx00:22 a=u7WPNUs3qKkmUXheDGA7:22 a=YMgV9FUhrdKAYTUUvYB2:22 a=HAiw8MWB_luJwFoROhsA:9 a=3ZKOabzyN94A:10 a=QEXdDO2ut3YA:10 a=NFOGd7dJGGMPyQGDc5-O:22 X-Proofpoint-GUID: 9DaKEXmT2M6n7MzqUaeDklZbuGpnqRiz X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwNzA0MDA2MyBTYWx0ZWRfX9iPkfzQnqmtP sCd7tOSTutjCut27UtXPamdErKhVFlPxq11HrzMCiVeszNxEJU5oUMQxM5VcXHPIquchlRqmJWM h58xkiXlRisufEqvKu5l6RGpP5Hl/O6wKx+/+wy4PPJvaiKMz29keZ4aROt4LLM/AYSZLr2C5pb h5ELBQTa2444IBmxCFhwAGtMaWG7/N69yOSblAg6eWJIoUrXi3U0TNTAAV2GpeF/8cjxgwxCaq9 gPO6tG+Kzjzcuz3eC4ZqglNmmNYWU59W48ND35DJyJR0M6EIYkwYAWD8yd1FrzLPrGg3JjbLLDn IYfVOanauFO7rMj8RnCs/UvW72+eAuAXPPjUXOdtuYUDu/hHq9NREupoEuKw3aPJUk2W+47TBOi 1fRQhad89EiuvUa3yC4FWCzwQLmMCQ9jv1dbFUm+m7GMz7+0XInHbNnJTyZ7ETGhDB0xaLflIH6 XY2M8cwJgDy5Gly2S3w== 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=2026-07-04_01,2026-07-03_01,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 suspectscore=0 malwarescore=0 spamscore=0 priorityscore=1501 adultscore=0 lowpriorityscore=0 phishscore=0 impostorscore=0 clxscore=1015 bulkscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2606150000 definitions=main-2607040063 Hi Sudeep, Le 03/07/2026 à 17:51, Sudeep Holla a écrit : > (It is always good to cc all PSCI maintainer for any ARM64 CPU > hotpug/suspend related changes) > > On Fri, Jul 03, 2026 at 04:50:02PM +0530, Sneh Mankad wrote: >> The Qualcomm SoCs like LeMans, Monaco support suspend to ram which leads >> the SoC to ACPI S3 similar state where SoC is turned off and DDR is >> retained. The hardware design on these SoCs forces a constraint to suspend >> and resume the system on boot CPU / CPU0. >> > And you fail to explain why they have that constraint. > > Is it because some secure context is not allowed to migrate ? > > We already have a mechanism for that in place and this hack is not at all > required. Do you mean a mechanism for the secure context or for preventing CPU0 ? Can you clarify ?