From 8ddf54a32111f6dbe06cd318af443c6545a6c037 Mon Sep 17 00:00:00 2001 From: Jeffrey Hugo Date: Fri, 5 Jan 2024 10:42:53 -0700 Subject: bus: mhi: host: Read PK HASH dynamically The OEM PK HASH registers in the BHI region are read once during firmware load (boot), cached, and displayed on demand via sysfs. This has a few problems - if firmware load is skipped, the registers will not be read and if the register values change over the life of the device the local cache will be out of sync. Qualcomm Cloud AI 100 can expose both these problems. It is possible for mhi_async_power_up() to be invoked while the device is in AMSS EE, which would bypass firmware loading. Also, Qualcomm Cloud AI 100 has 5 PK HASH slots which can be dynamically provisioned while the device is active, which would result in the values changing and users may want to know what keys are active. Address these concerns by reading the PK HASH registers on-demand during the sysfs read. This will result in showing the most current information. Signed-off-by: Jeffrey Hugo Reviewed-by: Pranjal Ramajor Asha Kanojiya Reviewed-by: Manivannan Sadhasivam Link: https://lore.kernel.org/r/20240105174253.863388-1-quic_jhugo@quicinc.com Signed-off-by: Manivannan Sadhasivam --- include/linux/mhi.h | 2 -- 1 file changed, 2 deletions(-) (limited to 'include/linux/mhi.h') diff --git a/include/linux/mhi.h b/include/linux/mhi.h index d0f9b522f328..474d32cb0520 100644 --- a/include/linux/mhi.h +++ b/include/linux/mhi.h @@ -325,7 +325,6 @@ struct mhi_controller_config { * @major_version: MHI controller major revision number * @minor_version: MHI controller minor revision number * @serial_number: MHI controller serial number obtained from BHI - * @oem_pk_hash: MHI controller OEM PK Hash obtained from BHI * @mhi_event: MHI event ring configurations table * @mhi_cmd: MHI command ring configurations table * @mhi_ctxt: MHI device context, shared memory between host and device @@ -413,7 +412,6 @@ struct mhi_controller { u32 major_version; u32 minor_version; u32 serial_number; - u32 oem_pk_hash[MHI_MAX_OEM_PK_HASH_SEGMENTS]; struct mhi_event *mhi_event; struct mhi_cmd *mhi_cmd; -- cgit From f0397e27d1204a7e6581d140c2de7fd11383c6ba Mon Sep 17 00:00:00 2001 From: Jeffrey Hugo Date: Mon, 19 Feb 2024 11:07:48 -0700 Subject: Revert "bus: mhi: core: Add support for reading MHI info from device" This reverts commit 3316ab2b45f6bf4797d8d65b22fda3cc13318890. The MHI spec owner pointed out that the SOC_HW_VERSION register is part of the BHIe segment, and only valid on devices which implement BHIe. Only a small subset of MHI devices implement BHIe so blindly accessing the register for all devices is not correct. Also, since the BHIe segment offset is not used when accessing the register, any implementation which moves the BHIe segment will result in accessing some other register. We've seen that accessing this register on AIC100 which does not support BHIe can result in initialization failures. We could try to put checks into the code to address these issues, but in the roughly 4 years this functionality has existed, no one has used it. Easier to drop this dead code and address the issues if anyone comes up with a real world use for it. Signed-off-by: Jeffrey Hugo Reviewed-by: Manivannan Sadhasivam Link: https://lore.kernel.org/r/20240219180748.1591527-1-quic_jhugo@quicinc.com Signed-off-by: Manivannan Sadhasivam --- drivers/bus/mhi/host/init.c | 12 ------------ drivers/bus/mhi/host/internal.h | 6 ------ include/linux/mhi.h | 17 ----------------- 3 files changed, 35 deletions(-) (limited to 'include/linux/mhi.h') diff --git a/drivers/bus/mhi/host/init.c b/drivers/bus/mhi/host/init.c index 944da46e6f11..44f934981de8 100644 --- a/drivers/bus/mhi/host/init.c +++ b/drivers/bus/mhi/host/init.c @@ -914,7 +914,6 @@ int mhi_register_controller(struct mhi_controller *mhi_cntrl, struct mhi_chan *mhi_chan; struct mhi_cmd *mhi_cmd; struct mhi_device *mhi_dev; - u32 soc_info; int ret, i; if (!mhi_cntrl || !mhi_cntrl->cntrl_dev || !mhi_cntrl->regs || @@ -989,17 +988,6 @@ int mhi_register_controller(struct mhi_controller *mhi_cntrl, mhi_cntrl->unmap_single = mhi_unmap_single_no_bb; } - /* Read the MHI device info */ - ret = mhi_read_reg(mhi_cntrl, mhi_cntrl->regs, - SOC_HW_VERSION_OFFS, &soc_info); - if (ret) - goto err_destroy_wq; - - mhi_cntrl->family_number = FIELD_GET(SOC_HW_VERSION_FAM_NUM_BMSK, soc_info); - mhi_cntrl->device_number = FIELD_GET(SOC_HW_VERSION_DEV_NUM_BMSK, soc_info); - mhi_cntrl->major_version = FIELD_GET(SOC_HW_VERSION_MAJOR_VER_BMSK, soc_info); - mhi_cntrl->minor_version = FIELD_GET(SOC_HW_VERSION_MINOR_VER_BMSK, soc_info); - mhi_cntrl->index = ida_alloc(&mhi_controller_ida, GFP_KERNEL); if (mhi_cntrl->index < 0) { ret = mhi_cntrl->index; diff --git a/drivers/bus/mhi/host/internal.h b/drivers/bus/mhi/host/internal.h index 091244cf17c6..5fe49311b8eb 100644 --- a/drivers/bus/mhi/host/internal.h +++ b/drivers/bus/mhi/host/internal.h @@ -15,12 +15,6 @@ extern struct bus_type mhi_bus_type; #define MHI_SOC_RESET_REQ_OFFSET 0xb0 #define MHI_SOC_RESET_REQ BIT(0) -#define SOC_HW_VERSION_OFFS 0x224 -#define SOC_HW_VERSION_FAM_NUM_BMSK GENMASK(31, 28) -#define SOC_HW_VERSION_DEV_NUM_BMSK GENMASK(27, 16) -#define SOC_HW_VERSION_MAJOR_VER_BMSK GENMASK(15, 8) -#define SOC_HW_VERSION_MINOR_VER_BMSK GENMASK(7, 0) - struct mhi_ctxt { struct mhi_event_ctxt *er_ctxt; struct mhi_chan_ctxt *chan_ctxt; diff --git a/include/linux/mhi.h b/include/linux/mhi.h index 474d32cb0520..77b8c0a26674 100644 --- a/include/linux/mhi.h +++ b/include/linux/mhi.h @@ -320,10 +320,6 @@ struct mhi_controller_config { * @hw_ev_rings: Number of hardware event rings * @sw_ev_rings: Number of software event rings * @nr_irqs: Number of IRQ allocated by bus master (required) - * @family_number: MHI controller family number - * @device_number: MHI controller device number - * @major_version: MHI controller major revision number - * @minor_version: MHI controller minor revision number * @serial_number: MHI controller serial number obtained from BHI * @mhi_event: MHI event ring configurations table * @mhi_cmd: MHI command ring configurations table @@ -368,15 +364,6 @@ struct mhi_controller_config { * Fields marked as (required) need to be populated by the controller driver * before calling mhi_register_controller(). For the fields marked as (optional) * they can be populated depending on the usecase. - * - * The following fields are present for the purpose of implementing any device - * specific quirks or customizations for specific MHI revisions used in device - * by the controller drivers. The MHI stack will just populate these fields - * during mhi_register_controller(): - * family_number - * device_number - * major_version - * minor_version */ struct mhi_controller { struct device *cntrl_dev; @@ -407,10 +394,6 @@ struct mhi_controller { u32 hw_ev_rings; u32 sw_ev_rings; u32 nr_irqs; - u32 family_number; - u32 device_number; - u32 major_version; - u32 minor_version; u32 serial_number; struct mhi_event *mhi_event; -- cgit