From: Hans Zhang <18255117159@163.com>
To: Shawn Lin <shawn.lin@rock-chips.com>,
bhelgaas@google.com, lpieralisi@kernel.org,
kwilczynski@kernel.org, mani@kernel.org, hans.zhang@cixtech.com
Cc: robh@kernel.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/2] PCI: cadence: Add debugfs property to provide LTSSM status of the PCIe link
Date: Tue, 17 Mar 2026 23:34:36 +0800 [thread overview]
Message-ID: <697466ce-5cbd-4d2e-95dc-c46e854f9e94@163.com> (raw)
In-Reply-To: <65b00ea8-1936-18ae-115b-3e356bd1cbaa@rock-chips.com>
On 2026/3/17 14:31, Shawn Lin wrote:
> 在 2026/03/15 星期日 23:55, Hans Zhang 写道:
>> Add the debugfs property to provide a view of the current link's LTSSM
>> status from the Root Port device.
>>
>> Test example:
>> # cat /sys/kernel/debug/cdns_pcie_a0c0000.pcie/ltssm_status
>> L0_STATE (0x29)
>>
>> Signed-off-by: Hans Zhang <18255117159@163.com>
>> ---
>> Documentation/ABI/testing/debugfs-cdns-pcie | 5 +
>> drivers/pci/controller/cadence/Kconfig | 9 +
>> drivers/pci/controller/cadence/Makefile | 1 +
>> .../controller/cadence/pcie-cadence-debugfs.c | 211 ++++++++++++++++++
>> .../pci/controller/cadence/pcie-cadence-ep.c | 2 +
>> .../cadence/pcie-cadence-host-hpa.c | 8 +-
>> .../controller/cadence/pcie-cadence-host.c | 8 +-
>> drivers/pci/controller/cadence/pcie-cadence.h | 145 ++++++++++++
>> 8 files changed, 387 insertions(+), 2 deletions(-)
>> create mode 100644 Documentation/ABI/testing/debugfs-cdns-pcie
>> create mode 100644 drivers/pci/controller/cadence/pcie-cadence-
>> debugfs.c
>>
>> diff --git a/Documentation/ABI/testing/debugfs-cdns-pcie b/
>> Documentation/ABI/testing/debugfs-cdns-pcie
>> new file mode 100644
>> index 000000000000..4118303e75f3
>> --- /dev/null
>> +++ b/Documentation/ABI/testing/debugfs-cdns-pcie
>> @@ -0,0 +1,5 @@
>> +What: /sys/kernel/debug/cdns_pcie_<dev>/ltssm_status
>> +Date: January 2026
>
> March?
>
Hi Shawn,
Thank you very much for your review comments. Because this patch was
released to my local environment quite early, it was released a long
time ago and has not been sent out yet. Will change.
>> +Contact: Hans Zhang <18255117159@163.com>
>> +Description: (RO) Read will return the current PCIe LTSSM state in
>> both
>> + string and raw value.
>> diff --git a/drivers/pci/controller/cadence/Kconfig b/drivers/pci/
>> controller/cadence/Kconfig
>> index 9e651d545973..b277c5f6e196 100644
>> --- a/drivers/pci/controller/cadence/Kconfig
>> +++ b/drivers/pci/controller/cadence/Kconfig
>> @@ -6,6 +6,15 @@ menu "Cadence-based PCIe controllers"
>> config PCIE_CADENCE
>> tristate
>> +config PCIE_CADENCE_DEBUGFS
>> + bool "Cadence PCIe debugfs entries"
>> + depends on DEBUG_FS
>> + depends on PCIE_CADENCE_HOST || PCIE_CADENCE_EP
>> + help
>> + Say Y here to enable debugfs entries for the PCIe controller.
>> These
>> + entries provide various debug features related to the
>> controller and
>> + the LTSSM status of link can be displayed.
>> +
>> config PCIE_CADENCE_HOST
>> tristate
>> depends on OF
>> diff --git a/drivers/pci/controller/cadence/Makefile b/drivers/pci/
>> controller/cadence/Makefile
>> index b8ec1cecfaa8..2cdc4617e0c2 100644
>> --- a/drivers/pci/controller/cadence/Makefile
>> +++ b/drivers/pci/controller/cadence/Makefile
>> @@ -4,6 +4,7 @@ pcie-cadence-host-mod-y := pcie-cadence-host-common.o
>> pcie-cadence-host.o pcie-c
>> pcie-cadence-ep-mod-y := pcie-cadence-ep.o
>> obj-$(CONFIG_PCIE_CADENCE) = pcie-cadence-mod.o
>> +obj-$(CONFIG_PCIE_CADENCE_DEBUGFS) += pcie-cadence-debugfs.o
>> obj-$(CONFIG_PCIE_CADENCE_HOST) += pcie-cadence-host-mod.o
>> obj-$(CONFIG_PCIE_CADENCE_EP) += pcie-cadence-ep-mod.o
>> obj-$(CONFIG_PCIE_CADENCE_PLAT) += pcie-cadence-plat.o
>> diff --git a/drivers/pci/controller/cadence/pcie-cadence-debugfs.c b/
>> drivers/pci/controller/cadence/pcie-cadence-debugfs.c
>> new file mode 100644
>> index 000000000000..568c7af6e18f
>> --- /dev/null
>> +++ b/drivers/pci/controller/cadence/pcie-cadence-debugfs.c
>> @@ -0,0 +1,211 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * PCIe controller driver for CIX's sky1 SoCs
>> + *
>> + * Copyright 2026 Cix Technology Group Co., Ltd.
>> + * Author: Hans Zhang <hans.zhang@cixtech.com>
>> + */
>> +
>> +#include <linux/debugfs.h>
>> +
>> +#include "pcie-cadence.h"
>> +
>> +#define CDNS_DEBUGFS_BUF_MAX 128
>> +
>> +static const char *ltssm_status_string(enum cdns_pcie_ltssm ltssm)
>> +{
>> + const char *str;
>> +
>> + switch (ltssm) {
>> +#define DW_PCIE_LTSSM_NAME(n) case n: str = #n; break
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_DETECT_QUIET);
>
> Seriously? Synopsys code in cdns driver?
The Synopsys code was also one that I submitted, but I forgot to make
any modifications. Will change.
>
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_DETECT_QUIET_ENTRY);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_DETECT_ACTIVE);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_DETECT_ACTIVE_1);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_DETECT_ACTIVE_2);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_DETECT_ACTIVE_3);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_RCVR_DETECTED_ST);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_RCVR_DETECTED_1);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_POLLING_ACTIVE);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_POLLING_ACTIVE_1);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_POLLING_ACTIVE_2);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_POLLING_ACTIVE_3);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_POLLING_COMPLIANCE);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_POLLING_COMPLIANCE_1);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_POLLING_CONFIG);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_POLLING_CONFIG_1);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_POLLING_CONFIG_2);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_CONFIG_LW_START_RC);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_CONFIG_LW_START_RC_1);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_CONFIG_LW_START_RC_2);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_CONFIG_LW_ACC_RC);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_CONFIG_LANENUM_WAIT_RC);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_CONFIG_LANENUM_WAIT_RC_1);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_CONFIG_LANENUM_ACC_RC);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_CONFIG_LW_START_EP);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_CONFIG_LW_START_EP_1);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_CONFIG_LW_START_EP_2);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_CONFIG_LW_ACC_EP);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_CONFIG_LANENUM_WAIT_EP);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_CONFIG_LANENUM_WAIT_EP_1);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_CONFIG_LANENUM_ACC_EP);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_CONFIG_LANENUM_ACC_EP_1);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_DUMMY_STATE_1);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_CONFIG_COMPLETE);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_CONFIG_COMPLETE_1);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_CONFIG_COMPLETE_2);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_CONFIG_IDLE);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_CONFIG_IDLE_1);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_DUMMY_STATE_2);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_DUMMY_STATE_3);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_DUMMY_STATE_4);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_L0_STATE);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_RECOVERY_RCVR_LOCK);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_RECOVERY_RCVR_LOCK_1);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_RECOVERY_RCVR_CFG);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_RECOVERY_RCVR_CFG_1);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_RECOVERY_IDLE);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_RECOVERY_IDLE_1);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_DISABLE_LINK);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_DISABLE_LINK_1);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_DISABLE_LINK_2);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_DISABLE_LINK_3);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_DISABLE_LINK_4);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_DISABLE_LINK_5);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_DISABLE_LINK_6);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_DISABLE_LINK_7);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_HOT_RESET);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_HOT_RESET_1);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_HOT_RESET_2);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_HOT_RESET_3);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_L0S_ENTRY);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_L0S_1);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_L0S_2);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_L0S_3);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_L0S_4);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_L0S_5);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_WAIT_FOR_LINK_TX);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_TX_FTS_ENTRY);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_TX_FTS_1);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_TX_FTS_2);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_TX_ELEC_IDLE_ST);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_TX_ELEC_IDLE_1);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_TX_ELEC_IDLE_2);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_TX_ELEC_IDLE_3);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_RECOVERY_SPEED);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_RECOVERY_SPEED_1);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_RECOVERY_SPEED_2);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_RECOVERY_SPEED_3);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_POLLING_COMPLIANCE_GEN23);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_POLLING_COMPLIANCE_GEN23_1);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_POLLING_COMPLIANCE_GEN23_2);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_POLLING_COMPLIANCE_GEN23_3);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_POLLING_COMPLIANCE_GEN23_4);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_POLLING_COMPLIANCE_GEN23_5);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_POLLING_COMPLIANCE_GEN23_6);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_POLLING_COMPLIANCE_GEN23_7);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_POLLING_COMPLIANCE_GEN23_8);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_LOOPBACK_SLAVE_ENTRY);
>> +
>> DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_LOOPBACK_SLAVE_ENTRY_FROM_RECOVERY);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_LOOPBACK_SLAVE_EXIT_1);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_LOOPBACK_SLAVE_EXIT);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_LOOPBACK_SLAVE_GEN2_1);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_LOOPBACK_SLAVE_GEN2_2);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_LOOPBACK_SLAVE_GEN2_3);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_LOOPBACK_SLAVE_GEN2_4);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_LOOPBACK_SLAVE_GEN2_5);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_LOOPBACK_SLAVE_ACTIVE);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_L1_ENTRY);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_L1_1);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_L1_2);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_L1_3);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_L1_4);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_L1_IDLE);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_L1_EXIT);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_L2_ENTRY);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_L2_1);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_L2_2);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_L2_3);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_L2_4);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_L2_5);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_L2_IDLE);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_LOOPBACK_MASTER_ENTRY);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_LOOPBACK_MASTER_ENTRY_1);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_LOOPBACK_MASTER_ENTRY_2);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_LOOPBACK_MASTER_ENTRY_3);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_LOOPBACK_MASTER_ENTRY_4);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_LOOPBACK_MASTER_ENTRY_5);
>> +
>> DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_LOOPBACK_MASTER_ENTRY_FROM_RECOVERY);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_LOOPBACK_MASTER_ACTIVE);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_LOOPBACK_MASTER_EXIT);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_LOOPBACK_MASTER_EXIT_1);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_LOOPBACK_MASTER_EXIT_2);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_RECOVERY_EQUALIZATION_PHASE0);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_RECOVERY_EQUALIZATION_PHASE1);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_RECOVERY_EQUALIZATION_PHASE2_1);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_RECOVERY_EQUALIZATION_PHASE2_2);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_RECOVERY_EQUALIZATION_PHASE3_1);
>> + DW_PCIE_LTSSM_NAME(CDNS_PCIE_LTSSM_RECOVERY_EQUALIZATION_PHASE3_2);
>> + default:
>> + str = "CDNS_PCIE_LTSSM_UNKNOWN";
>> + break;
>> + }
>> +
>> + return str + strlen("CDNS_PCIE_LTSSM_");
>> +}
>> +
>> +static int ltssm_status_show(struct seq_file *s, void *v)
>> +{
>> + struct cdns_pcie *pci = s->private;
>> + enum cdns_pcie_ltssm ltssm;
>> + u32 reg;
>> +
>> + if (pci->is_hpa) {
>> + reg = cdns_pcie_hpa_readl(pci, REG_BANK_IP_REG,
>> + CDNS_PCIE_HPA_PHY_DBG_STS_REG0);
>> + ltssm = FIELD_GET(GENMASK(27, 20), reg);
>> + } else {
>> + reg = cdns_pcie_readl(pci, CDNS_PCIE_LM_BASE);
>> + ltssm = FIELD_GET(GENMASK(29, 24), reg);
>> + }
>
> What are these magic numbers? Please use macro with proper
> names.
Will Change.
Best regards,
Hans
>
>> +
>> + seq_printf(s, "%s (0x%02x)\n", ltssm_status_string(ltssm), ltssm);
>> +
>> + return 0;
>> +}
>> +
>> +static int ltssm_status_open(struct inode *inode, struct file *file)
>> +{
>> + return single_open(file, ltssm_status_show, inode->i_private);
>> +}
>> +
>> +static const struct file_operations cdns_pcie_ltssm_status_ops = {
>> + .open = ltssm_status_open,
>> + .read = seq_read,
>> +};
>> +
>> +static void cdns_pcie_ltssm_debugfs_init(struct cdns_pcie *pci,
>> struct dentry *dir)
>> +{
>> + debugfs_create_file("ltssm_status", 0444, dir, pci,
>> + &cdns_pcie_ltssm_status_ops);
>> +}
>> +
>> +void cdns_pcie_debugfs_deinit(struct cdns_pcie *pci)
>> +{
>> + if (!pci->debug_dir)
>> + return;
>> +
>> + debugfs_remove_recursive(pci->debug_dir);
>> +}
>> +
>> +void cdns_pcie_debugfs_init(struct cdns_pcie *pci)
>> +{
>> + char dirname[CDNS_DEBUGFS_BUF_MAX];
>> + struct device *dev = pci->dev;
>> +
>> + /* Create main directory for each platform driver. */
>> + snprintf(dirname, CDNS_DEBUGFS_BUF_MAX, "cdns_pcie_%s",
>> dev_name(dev));
>> + pci->debug_dir = debugfs_create_dir(dirname, NULL);
>> +
>> + cdns_pcie_ltssm_debugfs_init(pci, pci->debug_dir);
>> +}
>> diff --git a/drivers/pci/controller/cadence/pcie-cadence-ep.c b/
>> drivers/pci/controller/cadence/pcie-cadence-ep.c
>> index c0e1194a936b..7849f63f53ab 100644
>> --- a/drivers/pci/controller/cadence/pcie-cadence-ep.c
>> +++ b/drivers/pci/controller/cadence/pcie-cadence-ep.c
>> @@ -761,6 +761,8 @@ int cdns_pcie_ep_setup(struct cdns_pcie_ep *ep)
>> pci_epc_init_notify(epc);
>> + cdns_pcie_debugfs_init(pcie);
>> +
>> return 0;
>> free_epc_mem:
>> diff --git a/drivers/pci/controller/cadence/pcie-cadence-host-hpa.c b/
>> drivers/pci/controller/cadence/pcie-cadence-host-hpa.c
>> index 0f540bed58e8..38bd74d9e071 100644
>> --- a/drivers/pci/controller/cadence/pcie-cadence-host-hpa.c
>> +++ b/drivers/pci/controller/cadence/pcie-cadence-host-hpa.c
>> @@ -360,7 +360,13 @@ int cdns_pcie_hpa_host_setup(struct cdns_pcie_rc
>> *rc)
>> if (!bridge->ops)
>> bridge->ops = &cdns_pcie_hpa_host_ops;
>> - return pci_host_probe(bridge);
>> + ret = pci_host_probe(bridge);
>> + if (ret)
>> + return ret;
>> +
>> + cdns_pcie_debugfs_init(pcie);
>> +
>> + return 0;
>> }
>> EXPORT_SYMBOL_GPL(cdns_pcie_hpa_host_setup);
>> diff --git a/drivers/pci/controller/cadence/pcie-cadence-host.c b/
>> drivers/pci/controller/cadence/pcie-cadence-host.c
>> index db3154c1eccb..23ca1e703953 100644
>> --- a/drivers/pci/controller/cadence/pcie-cadence-host.c
>> +++ b/drivers/pci/controller/cadence/pcie-cadence-host.c
>> @@ -416,7 +416,13 @@ int cdns_pcie_host_setup(struct cdns_pcie_rc *rc)
>> if (!bridge->ops)
>> bridge->ops = &cdns_pcie_host_ops;
>> - return pci_host_probe(bridge);
>> + ret = pci_host_probe(bridge);
>> + if (ret)
>> + return ret;
>> +
>> + cdns_pcie_debugfs_init(pcie);
>> +
>> + return 0;
>> }
>> EXPORT_SYMBOL_GPL(cdns_pcie_host_setup);
>> diff --git a/drivers/pci/controller/cadence/pcie-cadence.h b/drivers/
>> pci/controller/cadence/pcie-cadence.h
>> index c8cb19f7622f..6db98b7d24cb 100644
>> --- a/drivers/pci/controller/cadence/pcie-cadence.h
>> +++ b/drivers/pci/controller/cadence/pcie-cadence.h
>> @@ -42,6 +42,137 @@ enum cdns_pcie_reg_bank {
>> REG_BANKS_MAX,
>> };
>> +enum cdns_pcie_ltssm {
>> + CDNS_PCIE_LTSSM_DETECT_QUIET = 0,
>> + CDNS_PCIE_LTSSM_DETECT_QUIET_ENTRY = 1,
>> + CDNS_PCIE_LTSSM_DETECT_ACTIVE = 2,
>> + CDNS_PCIE_LTSSM_DETECT_ACTIVE_1 = 3,
>> + CDNS_PCIE_LTSSM_DETECT_ACTIVE_2 = 4,
>> + CDNS_PCIE_LTSSM_DETECT_ACTIVE_3 = 5,
>> + CDNS_PCIE_LTSSM_RCVR_DETECTED_ST = 6,
>> + CDNS_PCIE_LTSSM_RCVR_DETECTED_1 = 7,
>> + CDNS_PCIE_LTSSM_POLLING_ACTIVE = 8,
>> + CDNS_PCIE_LTSSM_POLLING_ACTIVE_1 = 9,
>> + CDNS_PCIE_LTSSM_POLLING_ACTIVE_2 = 10,
>> + CDNS_PCIE_LTSSM_POLLING_ACTIVE_3 = 11,
>> + CDNS_PCIE_LTSSM_POLLING_COMPLIANCE = 12,
>> + CDNS_PCIE_LTSSM_POLLING_COMPLIANCE_1 = 13,
>> + CDNS_PCIE_LTSSM_POLLING_CONFIG = 14,
>> + CDNS_PCIE_LTSSM_POLLING_CONFIG_1 = 15,
>> + CDNS_PCIE_LTSSM_POLLING_CONFIG_2 = 16,
>> + CDNS_PCIE_LTSSM_CONFIG_LW_START_RC = 17,
>> + CDNS_PCIE_LTSSM_CONFIG_LW_START_RC_1 = 18,
>> + CDNS_PCIE_LTSSM_CONFIG_LW_START_RC_2 = 19,
>> + CDNS_PCIE_LTSSM_CONFIG_LW_ACC_RC = 20,
>> + CDNS_PCIE_LTSSM_CONFIG_LANENUM_WAIT_RC = 21,
>> + CDNS_PCIE_LTSSM_CONFIG_LANENUM_WAIT_RC_1 = 22,
>> + CDNS_PCIE_LTSSM_CONFIG_LANENUM_ACC_RC = 23,
>> + CDNS_PCIE_LTSSM_CONFIG_LW_START_EP = 24,
>> + CDNS_PCIE_LTSSM_CONFIG_LW_START_EP_1 = 25,
>> + CDNS_PCIE_LTSSM_CONFIG_LW_START_EP_2 = 26,
>> + CDNS_PCIE_LTSSM_CONFIG_LW_ACC_EP = 27,
>> + CDNS_PCIE_LTSSM_CONFIG_LANENUM_WAIT_EP = 28,
>> + CDNS_PCIE_LTSSM_CONFIG_LANENUM_WAIT_EP_1 = 29,
>> + CDNS_PCIE_LTSSM_CONFIG_LANENUM_ACC_EP = 30,
>> + CDNS_PCIE_LTSSM_CONFIG_LANENUM_ACC_EP_1 = 31,
>> + CDNS_PCIE_LTSSM_DUMMY_STATE_1 = 32,
>> + CDNS_PCIE_LTSSM_CONFIG_COMPLETE = 33,
>> + CDNS_PCIE_LTSSM_CONFIG_COMPLETE_1 = 34,
>> + CDNS_PCIE_LTSSM_CONFIG_COMPLETE_2 = 35,
>> + CDNS_PCIE_LTSSM_CONFIG_IDLE = 36,
>> + CDNS_PCIE_LTSSM_CONFIG_IDLE_1 = 37,
>> + CDNS_PCIE_LTSSM_DUMMY_STATE_2 = 38,
>> + CDNS_PCIE_LTSSM_DUMMY_STATE_3 = 39,
>> + CDNS_PCIE_LTSSM_DUMMY_STATE_4 = 40,
>> + CDNS_PCIE_LTSSM_L0_STATE = 41,
>> + CDNS_PCIE_LTSSM_RECOVERY_RCVR_LOCK = 42,
>> + CDNS_PCIE_LTSSM_RECOVERY_RCVR_LOCK_1 = 43,
>> + CDNS_PCIE_LTSSM_RECOVERY_RCVR_CFG = 44,
>> + CDNS_PCIE_LTSSM_RECOVERY_RCVR_CFG_1 = 45,
>> + CDNS_PCIE_LTSSM_RECOVERY_IDLE = 46,
>> + CDNS_PCIE_LTSSM_RECOVERY_IDLE_1 = 47,
>> + CDNS_PCIE_LTSSM_DISABLE_LINK = 48,
>> + CDNS_PCIE_LTSSM_DISABLE_LINK_1 = 49,
>> + CDNS_PCIE_LTSSM_DISABLE_LINK_2 = 50,
>> + CDNS_PCIE_LTSSM_DISABLE_LINK_3 = 51,
>> + CDNS_PCIE_LTSSM_DISABLE_LINK_4 = 52,
>> + CDNS_PCIE_LTSSM_DISABLE_LINK_5 = 53,
>> + CDNS_PCIE_LTSSM_DISABLE_LINK_6 = 54,
>> + CDNS_PCIE_LTSSM_DISABLE_LINK_7 = 55,
>> + CDNS_PCIE_LTSSM_HOT_RESET = 56,
>> + CDNS_PCIE_LTSSM_HOT_RESET_1 = 57,
>> + CDNS_PCIE_LTSSM_HOT_RESET_2 = 58,
>> + CDNS_PCIE_LTSSM_HOT_RESET_3 = 59,
>> + CDNS_PCIE_LTSSM_L0S_ENTRY = 60,
>> + CDNS_PCIE_LTSSM_L0S_1 = 61,
>> + CDNS_PCIE_LTSSM_L0S_2 = 62,
>> + CDNS_PCIE_LTSSM_L0S_3 = 63,
>> + CDNS_PCIE_LTSSM_L0S_4 = 64,
>> + CDNS_PCIE_LTSSM_L0S_5 = 65,
>> + CDNS_PCIE_LTSSM_WAIT_FOR_LINK_TX = 66,
>> + CDNS_PCIE_LTSSM_TX_FTS_ENTRY = 67,
>> + CDNS_PCIE_LTSSM_TX_FTS_1 = 68,
>> + CDNS_PCIE_LTSSM_TX_FTS_2 = 69,
>> + CDNS_PCIE_LTSSM_TX_ELEC_IDLE_ST = 70,
>> + CDNS_PCIE_LTSSM_TX_ELEC_IDLE_1 = 71,
>> + CDNS_PCIE_LTSSM_TX_ELEC_IDLE_2 = 72,
>> + CDNS_PCIE_LTSSM_TX_ELEC_IDLE_3 = 73,
>> + CDNS_PCIE_LTSSM_RECOVERY_SPEED = 74,
>> + CDNS_PCIE_LTSSM_RECOVERY_SPEED_1 = 75,
>> + CDNS_PCIE_LTSSM_RECOVERY_SPEED_2 = 76,
>> + CDNS_PCIE_LTSSM_RECOVERY_SPEED_3 = 77,
>> + CDNS_PCIE_LTSSM_POLLING_COMPLIANCE_GEN23 = 78,
>> + CDNS_PCIE_LTSSM_POLLING_COMPLIANCE_GEN23_1 = 79,
>> + CDNS_PCIE_LTSSM_POLLING_COMPLIANCE_GEN23_2 = 80,
>> + CDNS_PCIE_LTSSM_POLLING_COMPLIANCE_GEN23_3 = 81,
>> + CDNS_PCIE_LTSSM_POLLING_COMPLIANCE_GEN23_4 = 82,
>> + CDNS_PCIE_LTSSM_POLLING_COMPLIANCE_GEN23_5 = 83,
>> + CDNS_PCIE_LTSSM_POLLING_COMPLIANCE_GEN23_6 = 84,
>> + CDNS_PCIE_LTSSM_POLLING_COMPLIANCE_GEN23_7 = 85,
>> + CDNS_PCIE_LTSSM_POLLING_COMPLIANCE_GEN23_8 = 86,
>> + CDNS_PCIE_LTSSM_LOOPBACK_SLAVE_ENTRY = 87,
>> + CDNS_PCIE_LTSSM_LOOPBACK_SLAVE_ENTRY_FROM_RECOVERY = 88,
>> + CDNS_PCIE_LTSSM_LOOPBACK_SLAVE_EXIT_1 = 89,
>> + CDNS_PCIE_LTSSM_LOOPBACK_SLAVE_EXIT = 90,
>> + CDNS_PCIE_LTSSM_LOOPBACK_SLAVE_GEN2_1 = 91,
>> + CDNS_PCIE_LTSSM_LOOPBACK_SLAVE_GEN2_2 = 92,
>> + CDNS_PCIE_LTSSM_LOOPBACK_SLAVE_GEN2_3 = 93,
>> + CDNS_PCIE_LTSSM_LOOPBACK_SLAVE_GEN2_4 = 94,
>> + CDNS_PCIE_LTSSM_LOOPBACK_SLAVE_GEN2_5 = 95,
>> + CDNS_PCIE_LTSSM_LOOPBACK_SLAVE_ACTIVE = 96,
>> + CDNS_PCIE_LTSSM_L1_ENTRY = 97,
>> + CDNS_PCIE_LTSSM_L1_1 = 98,
>> + CDNS_PCIE_LTSSM_L1_2 = 99,
>> + CDNS_PCIE_LTSSM_L1_3 = 100,
>> + CDNS_PCIE_LTSSM_L1_4 = 101,
>> + CDNS_PCIE_LTSSM_L1_IDLE = 102,
>> + CDNS_PCIE_LTSSM_L1_EXIT = 103,
>> + CDNS_PCIE_LTSSM_L2_ENTRY = 104,
>> + CDNS_PCIE_LTSSM_L2_1 = 105,
>> + CDNS_PCIE_LTSSM_L2_2 = 106,
>> + CDNS_PCIE_LTSSM_L2_3 = 107,
>> + CDNS_PCIE_LTSSM_L2_4 = 108,
>> + CDNS_PCIE_LTSSM_L2_5 = 109,
>> + CDNS_PCIE_LTSSM_L2_IDLE = 110,
>> + CDNS_PCIE_LTSSM_LOOPBACK_MASTER_ENTRY = 111,
>> + CDNS_PCIE_LTSSM_LOOPBACK_MASTER_ENTRY_1 = 112,
>> + CDNS_PCIE_LTSSM_LOOPBACK_MASTER_ENTRY_2 = 113,
>> + CDNS_PCIE_LTSSM_LOOPBACK_MASTER_ENTRY_3 = 114,
>> + CDNS_PCIE_LTSSM_LOOPBACK_MASTER_ENTRY_4 = 115,
>> + CDNS_PCIE_LTSSM_LOOPBACK_MASTER_ENTRY_5 = 116,
>> + CDNS_PCIE_LTSSM_LOOPBACK_MASTER_ENTRY_FROM_RECOVERY = 117,
>> + CDNS_PCIE_LTSSM_LOOPBACK_MASTER_ACTIVE = 118,
>> + CDNS_PCIE_LTSSM_LOOPBACK_MASTER_EXIT = 119,
>> + CDNS_PCIE_LTSSM_LOOPBACK_MASTER_EXIT_1 = 120,
>> + CDNS_PCIE_LTSSM_LOOPBACK_MASTER_EXIT_2 = 121,
>> + CDNS_PCIE_LTSSM_RECOVERY_EQUALIZATION_PHASE0 = 122,
>> + CDNS_PCIE_LTSSM_RECOVERY_EQUALIZATION_PHASE1 = 123,
>> + CDNS_PCIE_LTSSM_RECOVERY_EQUALIZATION_PHASE2_1 = 124,
>> + CDNS_PCIE_LTSSM_RECOVERY_EQUALIZATION_PHASE2_2 = 125,
>> + CDNS_PCIE_LTSSM_RECOVERY_EQUALIZATION_PHASE3_1 = 126,
>> + CDNS_PCIE_LTSSM_RECOVERY_EQUALIZATION_PHASE3_2 = 127,
>> +};
>> +
>> struct cdns_pcie_ops {
>> int (*start_link)(struct cdns_pcie *pcie);
>> void (*stop_link)(struct cdns_pcie *pcie);
>> @@ -87,6 +218,7 @@ struct cdns_plat_pcie_of_data {
>> * @ops: Platform-specific ops to control various inputs from
>> Cadence PCIe
>> * wrapper
>> * @cdns_pcie_reg_offsets: Register bank offsets for different SoC
>> + * @debug_dir: debugfs node
>> */
>> struct cdns_pcie {
>> void __iomem *reg_base;
>> @@ -100,6 +232,7 @@ struct cdns_pcie {
>> struct device_link **link;
>> const struct cdns_pcie_ops *ops;
>> const struct cdns_plat_pcie_of_data *cdns_pcie_reg_offsets;
>> + struct dentry *debug_dir;
>> };
>> /**
>> @@ -522,4 +655,16 @@ bool cdns_pcie_hpa_link_up(struct cdns_pcie *pcie);
>> extern const struct dev_pm_ops cdns_pcie_pm_ops;
>> +#ifdef CONFIG_PCIE_CADENCE_DEBUGFS
>> +void cdns_pcie_debugfs_deinit(struct cdns_pcie *pci);
>> +void cdns_pcie_debugfs_init(struct cdns_pcie *pci);
>> +#else
>> +static inline void cdns_pcie_debugfs_deinit(struct cdns_pcie *pci)
>> +{
>> +}
>> +static inline void cdns_pcie_debugfs_init(struct cdns_pcie *pci)
>> +{
>> +}
>> +#endif
>> +
>> #endif /* _PCIE_CADENCE_H */
>>
prev parent reply other threads:[~2026-03-17 15:35 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-03-15 15:55 [PATCH 0/2] Subject: [PATCH 0/2] PCI: cadence: Add LTSSM debugfs Hans Zhang
2026-03-15 15:55 ` [PATCH 1/2] PCI: cadence: Add HPA architecture flag Hans Zhang
2026-03-15 15:55 ` [PATCH 2/2] PCI: cadence: Add debugfs property to provide LTSSM status of the PCIe link Hans Zhang
2026-03-16 17:07 ` kernel test robot
2026-03-17 6:31 ` Shawn Lin
2026-03-17 15:34 ` Hans Zhang [this message]
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