Re: [PATCH v2 2/2] bus: mhi: host: pci_generic: Add edl callback to enter EDL

From: Jeffrey Hugo
Date: Thu Apr 11 2024 - 10:46:30 EST


On 4/10/2024 9:15 PM, Qiang Yu wrote:
Add mhi_pci_generic_edl_trigger as edl_trigger for some devices (eg. SDX65)
to enter EDL mode by writing the 0xEDEDEDED cookie to the channel 91
doorbell register and forcing an SOC reset afterwards.

Signed-off-by: Qiang Yu <quic_qianyu@xxxxxxxxxxx>
---
drivers/bus/mhi/host/pci_generic.c | 50 ++++++++++++++++++++++++++++++++++++++
1 file changed, 50 insertions(+)

diff --git a/drivers/bus/mhi/host/pci_generic.c b/drivers/bus/mhi/host/pci_generic.c
index 51639bf..a529815 100644
--- a/drivers/bus/mhi/host/pci_generic.c
+++ b/drivers/bus/mhi/host/pci_generic.c
@@ -27,12 +27,23 @@
#define PCI_VENDOR_ID_THALES 0x1269
#define PCI_VENDOR_ID_QUECTEL 0x1eac
+#define MHI_EDL_DB 91
+#define MHI_EDL_COOKIE 0xEDEDEDED
+
+/* Device can enter EDL by first setting edl cookie then issuing inband reset*/
+#define MHI_PCI_GENERIC_EDL_TRIGGER BIT(0)
+
+#define CHDBOFF 0x18

This is already in drivers/bus/mhi/common.h why duplicate it here?

+#define CHDBOFF_CHDBOFF_MASK 0xFFFFFFFF
+#define CHDBOFF_CHDBOFF_SHIFT 0
+
/**
* struct mhi_pci_dev_info - MHI PCI device specific information
* @config: MHI controller configuration
* @name: name of the PCI module
* @fw: firmware path (if any)
* @edl: emergency download mode firmware path (if any)
+ * @edl_trigger: each bit represents a different way to enter EDL
* @bar_num: PCI base address register to use for MHI MMIO register space
* @dma_data_width: DMA transfer word size (32 or 64 bits)
* @mru_default: default MRU size for MBIM network packets
@@ -44,6 +55,7 @@ struct mhi_pci_dev_info {
const char *name;
const char *fw;
const char *edl;
+ unsigned int edl_trigger;
unsigned int bar_num;
unsigned int dma_data_width;
unsigned int mru_default;
@@ -292,6 +304,7 @@ static const struct mhi_pci_dev_info mhi_qcom_sdx75_info = {
.name = "qcom-sdx75m",
.fw = "qcom/sdx75m/xbl.elf",
.edl = "qcom/sdx75m/edl.mbn",
+ .edl_trigger = MHI_PCI_GENERIC_EDL_TRIGGER,
.config = &modem_qcom_v2_mhiv_config,
.bar_num = MHI_PCI_DEFAULT_BAR_NUM,
.dma_data_width = 32,
@@ -302,6 +315,7 @@ static const struct mhi_pci_dev_info mhi_qcom_sdx65_info = {
.name = "qcom-sdx65m",
.fw = "qcom/sdx65m/xbl.elf",
.edl = "qcom/sdx65m/edl.mbn",
+ .edl_trigger = MHI_PCI_GENERIC_EDL_TRIGGER,
.config = &modem_qcom_v1_mhiv_config,
.bar_num = MHI_PCI_DEFAULT_BAR_NUM,
.dma_data_width = 32,
@@ -312,6 +326,7 @@ static const struct mhi_pci_dev_info mhi_qcom_sdx55_info = {
.name = "qcom-sdx55m",
.fw = "qcom/sdx55m/sbl1.mbn",
.edl = "qcom/sdx55m/edl.mbn",
+ .edl_trigger = MHI_PCI_GENERIC_EDL_TRIGGER,
.config = &modem_qcom_v1_mhiv_config,
.bar_num = MHI_PCI_DEFAULT_BAR_NUM,
.dma_data_width = 32,
@@ -928,6 +943,38 @@ static void health_check(struct timer_list *t)
mod_timer(&mhi_pdev->health_check_timer, jiffies + HEALTH_CHECK_PERIOD);
}
+static int mhi_pci_generic_edl_trigger(struct mhi_controller *mhi_cntrl)
+{
+ int ret;
+ u32 val;
+ void __iomem *edl_db;
+ void __iomem *base = mhi_cntrl->regs;

It looks like this file follows reverse christmas tree, but this function does not. you should fix it.

+
+ ret = mhi_device_get_sync(mhi_cntrl->mhi_dev);
+ if (ret) {
+ dev_err(mhi_cntrl->cntrl_dev, "Wake up device fail before trigger EDL\n");
+ return ret;
+ }
+
+ pm_wakeup_event(&mhi_cntrl->mhi_dev->dev, 0);
+ mhi_cntrl->runtime_get(mhi_cntrl);
+
+ mhi_cntrl->read_reg(mhi_cntrl, base + CHDBOFF, &val);
+ val = (val & CHDBOFF_CHDBOFF_MASK) >> CHDBOFF_CHDBOFF_SHIFT;
+
+ edl_db = base + val + (8 * MHI_EDL_DB);
+
+ mhi_cntrl->write_reg(mhi_cntrl, edl_db + 4, upper_32_bits(MHI_EDL_COOKIE));
+ mhi_cntrl->write_reg(mhi_cntrl, edl_db, lower_32_bits(MHI_EDL_COOKIE));
+
+ mhi_soc_reset(mhi_cntrl);
+
+ mhi_cntrl->runtime_put(mhi_cntrl);
+ mhi_device_put(mhi_cntrl->mhi_dev);
+
+ return 0;
+}
+
static int mhi_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
{
const struct mhi_pci_dev_info *info = (struct mhi_pci_dev_info *) id->driver_data;
@@ -962,6 +1009,9 @@ static int mhi_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
mhi_cntrl->runtime_put = mhi_pci_runtime_put;
mhi_cntrl->mru = info->mru_default;
+ if (info->edl_trigger & MHI_PCI_GENERIC_EDL_TRIGGER)
+ mhi_cntrl->edl_trigger = mhi_pci_generic_edl_trigger;
+
if (info->sideband_wake) {
mhi_cntrl->wake_get = mhi_pci_wake_get_nop;
mhi_cntrl->wake_put = mhi_pci_wake_put_nop;