Merge "mhi: core: Prevent doorbell with invalid tre" (54a42cb3) · Commits · e / devices / android_kernel_oneplus_sm7250

drivers/bus/mhi/core/mhi_main.c

+18 −17

Original line number	Diff line number	Diff line
		// SPDX-License-Identifier: GPL-2.0-only
		/* Copyright (c) 2018-2020, The Linux Foundation. All rights reserved. */
		/* Copyright (c) 2018-2021, The Linux Foundation. All rights reserved. */

		#include <linux/debugfs.h>
		#include <linux/device.h>
		@@ -558,18 +558,6 @@ int mhi_queue_dma(struct mhi_device *mhi_dev,
		mhi_tre->dword[0] =
		MHI_RSCTRE_DATA_DWORD0(buf_ring->wp - buf_ring->base);
		mhi_tre->dword[1] = MHI_RSCTRE_DATA_DWORD1;
		/*
		* on RSC channel IPA HW has a minimum credit requirement before
		* switching to DB mode
		*/
		n_free_tre = mhi_get_no_free_descriptors(mhi_dev,
		DMA_FROM_DEVICE);
		n_queued_tre = tre_ring->elements - n_free_tre;
		read_lock_bh(&mhi_chan->lock);
		if (mhi_chan->db_cfg.db_mode &&
		n_queued_tre < MHI_RSC_MIN_CREDITS)
		ring_db = false;
		read_unlock_bh(&mhi_chan->lock);
		} else {
		mhi_tre->ptr = MHI_TRE_DATA_PTR(buf_info->p_addr);
		mhi_tre->dword[0] = MHI_TRE_DATA_DWORD0(buf_info->len);
		@@ -587,11 +575,24 @@ int mhi_queue_dma(struct mhi_device *mhi_dev,
		if (mhi_chan->dir == DMA_TO_DEVICE)
		atomic_inc(&mhi_cntrl->pending_pkts);

		if (likely(MHI_DB_ACCESS_VALID(mhi_cntrl)) && ring_db) {
		read_lock_bh(&mhi_chan->lock);
		if (mhi_chan->xfer_type == MHI_XFER_RSC_DMA) {
		/*
		* on RSC channel IPA HW has a minimum credit requirement before
		* switching to DB mode
		*/
		n_free_tre = mhi_get_no_free_descriptors(mhi_dev,
		DMA_FROM_DEVICE);
		n_queued_tre = tre_ring->elements - n_free_tre;
		if (mhi_chan->db_cfg.db_mode &&
		n_queued_tre < MHI_RSC_MIN_CREDITS)
		ring_db = false;
		}

		if (likely(MHI_DB_ACCESS_VALID(mhi_cntrl)) && ring_db)
		mhi_ring_chan_db(mhi_cntrl, mhi_chan);

		read_unlock_bh(&mhi_chan->lock);
		}

		read_unlock_bh(&mhi_cntrl->pm_lock);