[PATCH 0/3] MHI fixes for v5.14

[PATCH 0/3] MHI fixes for v5.14

[Manivannan Sadhasivam]

Hi Greg,

Here are the MHI fixes for v5.14. 2 of these patches missed the 5.14 merge
window and one has been added recently.

Summary:

1. Fixed the MHI wake routines used for the newer modems such as SDX55 and
SDX65 by using no-op routines only for the older modems and then relying on
the default routines provided by MHI stack for newer ones.

2. Added validation for the channel ID read from event ring. If we get events
from an invalid channel, we throw an error message and skip the event.

3. Fixed the broken QRTR implementation due to the missing auto_queue flag in
the corresponding DL channel declaration.

Please consider merging!

Thanks,
Mani

Bhaumik Bhatt (2):
  bus: mhi: pci_generic: Apply no-op for wake using sideband wake
    boolean
  bus: mhi: core: Validate channel ID when processing command
    completions

Loic Poulain (1):
  bus: mhi: pci_generic: Fix inbound IPCR channel

 drivers/bus/mhi/core/main.c   | 17 +++++++++----
 drivers/bus/mhi/pci_generic.c | 45 ++++++++++++++++++++++++++++-------
 2 files changed, 48 insertions(+), 14 deletions(-)

-- 
2.25.1

[PATCH 1/3] bus: mhi: pci_generic: Apply no-op for wake using sideband wake boolean

[Manivannan Sadhasivam]

From: Bhaumik Bhatt <bbhatt@codeaurora.org>

Devices such as SDX24 do not have the provision for inband wake
doorbell in the form of channel 127 and instead have a sideband
GPIO for it. Newer devices such as SDX55 or SDX65 support inband
wake method by default. Ensure the functionality is used based on
this such that device wake stays held when a client driver uses
mhi_device_get() API or the equivalent debugfs entry.

Cc: stable@vger.kernel.org #5.12
Fixes: e3e5e6508fc1 ("bus: mhi: pci_generic: No-Op for device_wake operations")
Signed-off-by: Bhaumik Bhatt <bbhatt@codeaurora.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/1624560809-30610-1-git-send-email-bbhatt@codeaurora.org
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
---
 drivers/bus/mhi/pci_generic.c | 27 +++++++++++++++++++--------
 1 file changed, 19 insertions(+), 8 deletions(-)

diff --git a/drivers/bus/mhi/pci_generic.c b/drivers/bus/mhi/pci_generic.c
index ca3bc40427f8..3396cb30ebec 100644
--- a/drivers/bus/mhi/pci_generic.c
+++ b/drivers/bus/mhi/pci_generic.c
@@ -32,6 +32,8 @@
  * @edl: emergency download mode firmware path (if any)
  * @bar_num: PCI base address register to use for MHI MMIO register space
  * @dma_data_width: DMA transfer word size (32 or 64 bits)
+ * @sideband_wake: Devices using dedicated sideband GPIO for wakeup instead
+ *		   of inband wake support (such as sdx24)
  */
 struct mhi_pci_dev_info {
 	const struct mhi_controller_config *config;
@@ -40,6 +42,7 @@ struct mhi_pci_dev_info {
 	const char *edl;
 	unsigned int bar_num;
 	unsigned int dma_data_width;
+	bool sideband_wake;
 };
 
 #define MHI_CHANNEL_CONFIG_UL(ch_num, ch_name, el_count, ev_ring) \
@@ -242,7 +245,8 @@ static const struct mhi_pci_dev_info mhi_qcom_sdx65_info = {
 	.edl = "qcom/sdx65m/edl.mbn",
 	.config = &modem_qcom_v1_mhiv_config,
 	.bar_num = MHI_PCI_DEFAULT_BAR_NUM,
-	.dma_data_width = 32
+	.dma_data_width = 32,
+	.sideband_wake = false,
 };
 
 static const struct mhi_pci_dev_info mhi_qcom_sdx55_info = {
@@ -251,7 +255,8 @@ static const struct mhi_pci_dev_info mhi_qcom_sdx55_info = {
 	.edl = "qcom/sdx55m/edl.mbn",
 	.config = &modem_qcom_v1_mhiv_config,
 	.bar_num = MHI_PCI_DEFAULT_BAR_NUM,
-	.dma_data_width = 32
+	.dma_data_width = 32,
+	.sideband_wake = false,
 };
 
 static const struct mhi_pci_dev_info mhi_qcom_sdx24_info = {
@@ -259,7 +264,8 @@ static const struct mhi_pci_dev_info mhi_qcom_sdx24_info = {
 	.edl = "qcom/prog_firehose_sdx24.mbn",
 	.config = &modem_qcom_v1_mhiv_config,
 	.bar_num = MHI_PCI_DEFAULT_BAR_NUM,
-	.dma_data_width = 32
+	.dma_data_width = 32,
+	.sideband_wake = true,
 };
 
 static const struct mhi_channel_config mhi_quectel_em1xx_channels[] = {
@@ -301,7 +307,8 @@ static const struct mhi_pci_dev_info mhi_quectel_em1xx_info = {
 	.edl = "qcom/prog_firehose_sdx24.mbn",
 	.config = &modem_quectel_em1xx_config,
 	.bar_num = MHI_PCI_DEFAULT_BAR_NUM,
-	.dma_data_width = 32
+	.dma_data_width = 32,
+	.sideband_wake = true,
 };
 
 static const struct mhi_channel_config mhi_foxconn_sdx55_channels[] = {
@@ -339,7 +346,8 @@ static const struct mhi_pci_dev_info mhi_foxconn_sdx55_info = {
 	.edl = "qcom/sdx55m/edl.mbn",
 	.config = &modem_foxconn_sdx55_config,
 	.bar_num = MHI_PCI_DEFAULT_BAR_NUM,
-	.dma_data_width = 32
+	.dma_data_width = 32,
+	.sideband_wake = false,
 };
 
 static const struct pci_device_id mhi_pci_id_table[] = {
@@ -640,9 +648,12 @@ static int mhi_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 	mhi_cntrl->status_cb = mhi_pci_status_cb;
 	mhi_cntrl->runtime_get = mhi_pci_runtime_get;
 	mhi_cntrl->runtime_put = mhi_pci_runtime_put;
-	mhi_cntrl->wake_get = mhi_pci_wake_get_nop;
-	mhi_cntrl->wake_put = mhi_pci_wake_put_nop;
-	mhi_cntrl->wake_toggle = mhi_pci_wake_toggle_nop;
+
+	if (info->sideband_wake) {
+		mhi_cntrl->wake_get = mhi_pci_wake_get_nop;
+		mhi_cntrl->wake_put = mhi_pci_wake_put_nop;
+		mhi_cntrl->wake_toggle = mhi_pci_wake_toggle_nop;
+	}
 
 	err = mhi_pci_claim(mhi_cntrl, info->bar_num, DMA_BIT_MASK(info->dma_data_width));
 	if (err)
-- 
2.25.1

[PATCH 2/3] bus: mhi: core: Validate channel ID when processing command completions

[Manivannan Sadhasivam]

From: Bhaumik Bhatt <bbhatt@codeaurora.org>

MHI reads the channel ID from the event ring element sent by the
device which can be any value between 0 and 255. In order to
prevent any out of bound accesses, add a check against the maximum
number of channels supported by the controller and those channels
not configured yet so as to skip processing of that event ring
element.

Cc: stable@vger.kernel.org #5.10
Fixes: 1d3173a3bae7 ("bus: mhi: core: Add support for processing events from client device")
Signed-off-by: Bhaumik Bhatt <bbhatt@codeaurora.org>
Reviewed-by: Hemant Kumar <hemantk@codeaurora.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reviewed-by: Jeffrey Hugo <quic_jhugo@quicinc.com>
Link: https://lore.kernel.org/r/1624558141-11045-1-git-send-email-bbhatt@codeaurora.org
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
---
 drivers/bus/mhi/core/main.c | 17 ++++++++++++-----
 1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/drivers/bus/mhi/core/main.c b/drivers/bus/mhi/core/main.c
index 22acde118bc3..fc9196f11cb7 100644
--- a/drivers/bus/mhi/core/main.c
+++ b/drivers/bus/mhi/core/main.c
@@ -773,11 +773,18 @@ static void mhi_process_cmd_completion(struct mhi_controller *mhi_cntrl,
 	cmd_pkt = mhi_to_virtual(mhi_ring, ptr);
 
 	chan = MHI_TRE_GET_CMD_CHID(cmd_pkt);
-	mhi_chan = &mhi_cntrl->mhi_chan[chan];
-	write_lock_bh(&mhi_chan->lock);
-	mhi_chan->ccs = MHI_TRE_GET_EV_CODE(tre);
-	complete(&mhi_chan->completion);
-	write_unlock_bh(&mhi_chan->lock);
+
+	if (chan < mhi_cntrl->max_chan &&
+	    mhi_cntrl->mhi_chan[chan].configured) {
+		mhi_chan = &mhi_cntrl->mhi_chan[chan];
+		write_lock_bh(&mhi_chan->lock);
+		mhi_chan->ccs = MHI_TRE_GET_EV_CODE(tre);
+		complete(&mhi_chan->completion);
+		write_unlock_bh(&mhi_chan->lock);
+	} else {
+		dev_err(&mhi_cntrl->mhi_dev->dev,
+			"Completion packet for invalid channel ID: %d\n", chan);
+	}
 
 	mhi_del_ring_element(mhi_cntrl, mhi_ring);
 }
-- 
2.25.1

[PATCH 3/3] bus: mhi: pci_generic: Fix inbound IPCR channel

[Manivannan Sadhasivam]

From: Loic Poulain <loic.poulain@linaro.org>

The qrtr-mhi client driver assumes that inbound buffers are
automatically allocated and queued by the MHI core, but this
doesn't happen for mhi pci devices since IPCR inbound channel is
not flagged with auto_queue, causing unusable IPCR (qrtr)
feature. Fix that.

Cc: stable@vger.kernel.org #5.10
Fixes: 855a70c12021 ("bus: mhi: Add MHI PCI support for WWAN modems")
Signed-off-by: Loic Poulain <loic.poulain@linaro.org>
Reviewed-by: Hemant kumar <hemantk@codeaurora.org>
Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
Link: https://lore.kernel.org/r/1625736749-24947-1-git-send-email-loic.poulain@linaro.org
[mani: fixed a spelling mistake in commit description]
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
---
 drivers/bus/mhi/pci_generic.c | 18 +++++++++++++++++-
 1 file changed, 17 insertions(+), 1 deletion(-)

diff --git a/drivers/bus/mhi/pci_generic.c b/drivers/bus/mhi/pci_generic.c
index 3396cb30ebec..4dd1077354af 100644
--- a/drivers/bus/mhi/pci_generic.c
+++ b/drivers/bus/mhi/pci_generic.c
@@ -75,6 +75,22 @@ struct mhi_pci_dev_info {
 		.doorbell_mode_switch = false,		\
 	}
 
+#define MHI_CHANNEL_CONFIG_DL_AUTOQUEUE(ch_num, ch_name, el_count, ev_ring) \
+	{						\
+		.num = ch_num,				\
+		.name = ch_name,			\
+		.num_elements = el_count,		\
+		.event_ring = ev_ring,			\
+		.dir = DMA_FROM_DEVICE,			\
+		.ee_mask = BIT(MHI_EE_AMSS),		\
+		.pollcfg = 0,				\
+		.doorbell = MHI_DB_BRST_DISABLE,	\
+		.lpm_notify = false,			\
+		.offload_channel = false,		\
+		.doorbell_mode_switch = false,		\
+		.auto_queue = true,			\
+	}
+
 #define MHI_EVENT_CONFIG_CTRL(ev_ring, el_count) \
 	{					\
 		.num_elements = el_count,	\
@@ -213,7 +229,7 @@ static const struct mhi_channel_config modem_qcom_v1_mhi_channels[] = {
 	MHI_CHANNEL_CONFIG_UL(14, "QMI", 4, 0),
 	MHI_CHANNEL_CONFIG_DL(15, "QMI", 4, 0),
 	MHI_CHANNEL_CONFIG_UL(20, "IPCR", 8, 0),
-	MHI_CHANNEL_CONFIG_DL(21, "IPCR", 8, 0),
+	MHI_CHANNEL_CONFIG_DL_AUTOQUEUE(21, "IPCR", 8, 0),
 	MHI_CHANNEL_CONFIG_UL_FP(34, "FIREHOSE", 32, 0),
 	MHI_CHANNEL_CONFIG_DL_FP(35, "FIREHOSE", 32, 0),
 	MHI_CHANNEL_CONFIG_HW_UL(100, "IP_HW0", 128, 2),
-- 
2.25.1