From: Damien Le Moal <dlemoal@kernel.org>
To: "Manivannan Sadhasivam" <manivannan.sadhasivam@linaro.org>,
"Lorenzo Pieralisi" <lpieralisi@kernel.org>,
"Kishon Vijay Abraham I" <kishon@kernel.org>,
"Shawn Lin" <shawn.lin@rock-chips.com>,
"Krzysztof Wilczyński" <kw@linux.com>,
"Bjorn Helgaas" <bhelgaas@google.com>,
"Heiko Stuebner" <heiko@sntech.de>,
linux-pci@vger.kernel.org, "Rob Herring" <robh@kernel.org>,
"Krzysztof Kozlowski" <krzysztof.kozlowski+dt@linaro.org>,
"Conor Dooley" <conor+dt@kernel.org>,
devicetree@vger.kernel.org
Cc: linux-rockchip@lists.infradead.org,
linux-arm-kernel@lists.infradead.org,
Rick Wertenbroek <rick.wertenbroek@gmail.com>,
Wilfred Mallawa <wilfred.mallawa@wdc.com>,
Niklas Cassel <cassel@kernel.org>
Subject: [PATCH v2 16/18] PCI: rockchip-ep: Improve link training
Date: Sat, 30 Mar 2024 13:19:26 +0900 [thread overview]
Message-ID: <20240330041928.1555578-17-dlemoal@kernel.org> (raw)
In-Reply-To: <20240330041928.1555578-1-dlemoal@kernel.org>
The Rockchip rk339 technical reference manual describe the endpoint mode
link training process clearly and states that:
Insure link training completion and success by observing link_st field
in PCIe Client BASIC_STATUS1 register change to 2'b11. If both side
support PCIe Gen2 speed, re-train can be Initiated by asserting the
Retrain Link field in Link Control and Status Register. The software
should insure the BASIC_STATUS0[negotiated_speed] changes to "1", that
indicates re-train to Gen2 successfully.
This procedure is very similar to what is done for the root-port mode in
rockchip_pcie_host_init_port().
Implement this link training procedure for the endpoint mode as well.
Given that the rk3399 SoC does not have an interrupt signaling link
status changes, training is implemented as a delayed work which is
rescheduled until the link training completes or the endpoint controller
is stopped. The link training work is first scheduled in
rockchip_pcie_ep_start() when the endpoint function is started. Link
training completion is signaled to the function using pci_epc_linkup().
Accordingly, the linkup_notifier field of the rockchip pci_epc_features
structure is changed to true.
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
---
drivers/pci/controller/pcie-rockchip-ep.c | 79 ++++++++++++++++++++++-
drivers/pci/controller/pcie-rockchip.h | 11 ++++
2 files changed, 89 insertions(+), 1 deletion(-)
diff --git a/drivers/pci/controller/pcie-rockchip-ep.c b/drivers/pci/controller/pcie-rockchip-ep.c
index 2767e8f1771d..4006e7dee71a 100644
--- a/drivers/pci/controller/pcie-rockchip-ep.c
+++ b/drivers/pci/controller/pcie-rockchip-ep.c
@@ -16,6 +16,8 @@
#include <linux/platform_device.h>
#include <linux/pci-epf.h>
#include <linux/sizes.h>
+#include <linux/workqueue.h>
+#include <linux/iopoll.h>
#include "pcie-rockchip.h"
@@ -48,6 +50,7 @@ struct rockchip_pcie_ep {
u64 irq_pci_addr;
u8 irq_pci_fn;
u8 irq_pending;
+ struct delayed_work link_training;
};
static void rockchip_pcie_clear_ep_ob_atu(struct rockchip_pcie *rockchip,
@@ -467,6 +470,8 @@ static int rockchip_pcie_ep_start(struct pci_epc *epc)
PCIE_CLIENT_CONF_ENABLE,
PCIE_CLIENT_CONFIG);
+ schedule_delayed_work(&ep->link_training, 0);
+
return 0;
}
@@ -475,6 +480,8 @@ static void rockchip_pcie_ep_stop(struct pci_epc *epc)
struct rockchip_pcie_ep *ep = epc_get_drvdata(epc);
struct rockchip_pcie *rockchip = &ep->rockchip;
+ cancel_delayed_work_sync(&ep->link_training);
+
/* Stop link training and disable configuration */
rockchip_pcie_write(rockchip,
PCIE_CLIENT_CONF_DISABLE |
@@ -482,8 +489,77 @@ static void rockchip_pcie_ep_stop(struct pci_epc *epc)
PCIE_CLIENT_CONFIG);
}
+static void rockchip_pcie_ep_retrain_link(struct rockchip_pcie *rockchip)
+{
+ u32 status;
+
+ status = rockchip_pcie_read(rockchip, PCIE_EP_CONFIG_LCS);
+ status |= PCI_EXP_LNKCTL_RL;
+ rockchip_pcie_write(rockchip, status, PCIE_EP_CONFIG_LCS);
+}
+
+static bool rockchip_pcie_ep_link_up(struct rockchip_pcie *rockchip)
+{
+ u32 val = rockchip_pcie_read(rockchip, PCIE_CLIENT_BASIC_STATUS1);
+
+ return PCIE_LINK_UP(val);
+}
+
+static void rockchip_pcie_ep_link_training(struct work_struct *work)
+{
+ struct rockchip_pcie_ep *ep =
+ container_of(work, struct rockchip_pcie_ep, link_training.work);
+ struct rockchip_pcie *rockchip = &ep->rockchip;
+ struct device *dev = rockchip->dev;
+ u32 val;
+ int ret;
+
+ /* Enable Gen1 training and wait for its completion */
+ ret = readl_poll_timeout(rockchip->apb_base + PCIE_CORE_CTRL,
+ val, PCIE_LINK_TRAINING_DONE(val), 50,
+ LINK_TRAIN_TIMEOUT);
+ if (ret)
+ goto again;
+
+ /* Make sure that the link is up */
+ ret = readl_poll_timeout(rockchip->apb_base + PCIE_CLIENT_BASIC_STATUS1,
+ val, PCIE_LINK_UP(val), 50,
+ LINK_TRAIN_TIMEOUT);
+ if (ret)
+ goto again;
+
+ /* Check the current speed */
+ val = rockchip_pcie_read(rockchip, PCIE_CORE_CTRL);
+ if (!PCIE_LINK_IS_GEN2(val) && rockchip->link_gen == 2) {
+ /* Enable retrain for gen2 */
+ rockchip_pcie_ep_retrain_link(rockchip);
+ readl_poll_timeout(rockchip->apb_base + PCIE_CORE_CTRL,
+ val, PCIE_LINK_IS_GEN2(val), 50,
+ LINK_TRAIN_TIMEOUT);
+ }
+
+ /* Check again that the link is up */
+ if (!rockchip_pcie_ep_link_up(rockchip))
+ goto again;
+
+ val = rockchip_pcie_read(rockchip, PCIE_CLIENT_BASIC_STATUS0);
+ dev_info(dev,
+ "Link UP (Negociated speed: %sGT/s, width: x%lu)\n",
+ (val & PCIE_CLIENT_NEG_LINK_SPEED) ? "5" : "2.5",
+ ((val & PCIE_CLIENT_NEG_LINK_WIDTH_MASK) >>
+ PCIE_CLIENT_NEG_LINK_WIDTH_SHIFT) << 1);
+
+ /* Notify the function */
+ pci_epc_linkup(ep->epc);
+
+ return;
+
+again:
+ schedule_delayed_work(&ep->link_training, msecs_to_jiffies(5));
+}
+
static const struct pci_epc_features rockchip_pcie_epc_features = {
- .linkup_notifier = false,
+ .linkup_notifier = true,
.msi_capable = true,
.msix_capable = false,
.align = ROCKCHIP_PCIE_AT_SIZE_ALIGN,
@@ -644,6 +720,7 @@ static int rockchip_pcie_ep_probe(struct platform_device *pdev)
rockchip = &ep->rockchip;
rockchip->is_rc = false;
rockchip->dev = dev;
+ INIT_DELAYED_WORK(&ep->link_training, rockchip_pcie_ep_link_training);
epc = devm_pci_epc_create(dev, &rockchip_pcie_epc_ops);
if (IS_ERR(epc)) {
diff --git a/drivers/pci/controller/pcie-rockchip.h b/drivers/pci/controller/pcie-rockchip.h
index 0263f158ee8d..3963b7097a91 100644
--- a/drivers/pci/controller/pcie-rockchip.h
+++ b/drivers/pci/controller/pcie-rockchip.h
@@ -26,6 +26,7 @@
#define MAX_LANE_NUM 4
#define MAX_REGION_LIMIT 32
#define MIN_EP_APERTURE 28
+#define LINK_TRAIN_TIMEOUT (5000 * USEC_PER_MSEC)
#define PCIE_CLIENT_BASE 0x0
#define PCIE_CLIENT_CONFIG (PCIE_CLIENT_BASE + 0x00)
@@ -50,6 +51,10 @@
#define PCIE_CLIENT_DEBUG_LTSSM_MASK GENMASK(5, 0)
#define PCIE_CLIENT_DEBUG_LTSSM_L1 0x18
#define PCIE_CLIENT_DEBUG_LTSSM_L2 0x19
+#define PCIE_CLIENT_BASIC_STATUS0 (PCIE_CLIENT_BASE + 0x44)
+#define PCIE_CLIENT_NEG_LINK_WIDTH_MASK GENMASK(7, 6)
+#define PCIE_CLIENT_NEG_LINK_WIDTH_SHIFT 6
+#define PCIE_CLIENT_NEG_LINK_SPEED BIT(5)
#define PCIE_CLIENT_BASIC_STATUS1 (PCIE_CLIENT_BASE + 0x48)
#define PCIE_CLIENT_LINK_STATUS_UP 0x00300000
#define PCIE_CLIENT_LINK_STATUS_MASK 0x00300000
@@ -87,6 +92,8 @@
#define PCIE_CORE_CTRL_MGMT_BASE 0x900000
#define PCIE_CORE_CTRL (PCIE_CORE_CTRL_MGMT_BASE + 0x000)
+#define PCIE_CORE_PL_CONF_LS_MASK 0x00000001
+#define PCIE_CORE_PL_CONF_LS_READY 0x00000001
#define PCIE_CORE_PL_CONF_SPEED_5G 0x00000008
#define PCIE_CORE_PL_CONF_SPEED_MASK 0x00000018
#define PCIE_CORE_PL_CONF_LANE_MASK 0x00000006
@@ -144,6 +151,7 @@
#define PCIE_RC_CONFIG_BASE 0xa00000
#define PCIE_EP_CONFIG_BASE 0xa00000
#define PCIE_EP_CONFIG_DID_VID (PCIE_EP_CONFIG_BASE + 0x00)
+#define PCIE_EP_CONFIG_LCS (PCIE_EP_CONFIG_BASE + 0xd0)
#define PCIE_RC_CONFIG_RID_CCR (PCIE_RC_CONFIG_BASE + 0x08)
#define PCIE_RC_CONFIG_DCR (PCIE_RC_CONFIG_BASE + 0xc4)
#define PCIE_RC_CONFIG_DCR_CSPL_SHIFT 18
@@ -155,6 +163,7 @@
#define PCIE_RC_CONFIG_LINK_CAP (PCIE_RC_CONFIG_BASE + 0xcc)
#define PCIE_RC_CONFIG_LINK_CAP_L0S BIT(10)
#define PCIE_RC_CONFIG_LCS (PCIE_RC_CONFIG_BASE + 0xd0)
+#define PCIE_EP_CONFIG_LCS (PCIE_EP_CONFIG_BASE + 0xd0)
#define PCIE_RC_CONFIG_L1_SUBSTATE_CTRL2 (PCIE_RC_CONFIG_BASE + 0x90c)
#define PCIE_RC_CONFIG_THP_CAP (PCIE_RC_CONFIG_BASE + 0x274)
#define PCIE_RC_CONFIG_THP_CAP_NEXT_MASK GENMASK(31, 20)
@@ -192,6 +201,8 @@
#define ROCKCHIP_VENDOR_ID 0x1d87
#define PCIE_LINK_IS_L2(x) \
(((x) & PCIE_CLIENT_DEBUG_LTSSM_MASK) == PCIE_CLIENT_DEBUG_LTSSM_L2)
+#define PCIE_LINK_TRAINING_DONE(x) \
+ (((x) & PCIE_CORE_PL_CONF_LS_MASK) == PCIE_CORE_PL_CONF_LS_READY)
#define PCIE_LINK_UP(x) \
(((x) & PCIE_CLIENT_LINK_STATUS_MASK) == PCIE_CLIENT_LINK_STATUS_UP)
#define PCIE_LINK_IS_GEN2(x) \
--
2.44.0
WARNING: multiple messages have this Message-ID (diff)
From: Damien Le Moal <dlemoal@kernel.org>
To: "Manivannan Sadhasivam" <manivannan.sadhasivam@linaro.org>,
"Lorenzo Pieralisi" <lpieralisi@kernel.org>,
"Kishon Vijay Abraham I" <kishon@kernel.org>,
"Shawn Lin" <shawn.lin@rock-chips.com>,
"Krzysztof Wilczyński" <kw@linux.com>,
"Bjorn Helgaas" <bhelgaas@google.com>,
"Heiko Stuebner" <heiko@sntech.de>,
linux-pci@vger.kernel.org, "Rob Herring" <robh@kernel.org>,
"Krzysztof Kozlowski" <krzysztof.kozlowski+dt@linaro.org>,
"Conor Dooley" <conor+dt@kernel.org>,
devicetree@vger.kernel.org
Cc: linux-rockchip@lists.infradead.org,
linux-arm-kernel@lists.infradead.org,
Rick Wertenbroek <rick.wertenbroek@gmail.com>,
Wilfred Mallawa <wilfred.mallawa@wdc.com>,
Niklas Cassel <cassel@kernel.org>
Subject: [PATCH v2 16/18] PCI: rockchip-ep: Improve link training
Date: Sat, 30 Mar 2024 13:19:26 +0900 [thread overview]
Message-ID: <20240330041928.1555578-17-dlemoal@kernel.org> (raw)
In-Reply-To: <20240330041928.1555578-1-dlemoal@kernel.org>
The Rockchip rk339 technical reference manual describe the endpoint mode
link training process clearly and states that:
Insure link training completion and success by observing link_st field
in PCIe Client BASIC_STATUS1 register change to 2'b11. If both side
support PCIe Gen2 speed, re-train can be Initiated by asserting the
Retrain Link field in Link Control and Status Register. The software
should insure the BASIC_STATUS0[negotiated_speed] changes to "1", that
indicates re-train to Gen2 successfully.
This procedure is very similar to what is done for the root-port mode in
rockchip_pcie_host_init_port().
Implement this link training procedure for the endpoint mode as well.
Given that the rk3399 SoC does not have an interrupt signaling link
status changes, training is implemented as a delayed work which is
rescheduled until the link training completes or the endpoint controller
is stopped. The link training work is first scheduled in
rockchip_pcie_ep_start() when the endpoint function is started. Link
training completion is signaled to the function using pci_epc_linkup().
Accordingly, the linkup_notifier field of the rockchip pci_epc_features
structure is changed to true.
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
---
drivers/pci/controller/pcie-rockchip-ep.c | 79 ++++++++++++++++++++++-
drivers/pci/controller/pcie-rockchip.h | 11 ++++
2 files changed, 89 insertions(+), 1 deletion(-)
diff --git a/drivers/pci/controller/pcie-rockchip-ep.c b/drivers/pci/controller/pcie-rockchip-ep.c
index 2767e8f1771d..4006e7dee71a 100644
--- a/drivers/pci/controller/pcie-rockchip-ep.c
+++ b/drivers/pci/controller/pcie-rockchip-ep.c
@@ -16,6 +16,8 @@
#include <linux/platform_device.h>
#include <linux/pci-epf.h>
#include <linux/sizes.h>
+#include <linux/workqueue.h>
+#include <linux/iopoll.h>
#include "pcie-rockchip.h"
@@ -48,6 +50,7 @@ struct rockchip_pcie_ep {
u64 irq_pci_addr;
u8 irq_pci_fn;
u8 irq_pending;
+ struct delayed_work link_training;
};
static void rockchip_pcie_clear_ep_ob_atu(struct rockchip_pcie *rockchip,
@@ -467,6 +470,8 @@ static int rockchip_pcie_ep_start(struct pci_epc *epc)
PCIE_CLIENT_CONF_ENABLE,
PCIE_CLIENT_CONFIG);
+ schedule_delayed_work(&ep->link_training, 0);
+
return 0;
}
@@ -475,6 +480,8 @@ static void rockchip_pcie_ep_stop(struct pci_epc *epc)
struct rockchip_pcie_ep *ep = epc_get_drvdata(epc);
struct rockchip_pcie *rockchip = &ep->rockchip;
+ cancel_delayed_work_sync(&ep->link_training);
+
/* Stop link training and disable configuration */
rockchip_pcie_write(rockchip,
PCIE_CLIENT_CONF_DISABLE |
@@ -482,8 +489,77 @@ static void rockchip_pcie_ep_stop(struct pci_epc *epc)
PCIE_CLIENT_CONFIG);
}
+static void rockchip_pcie_ep_retrain_link(struct rockchip_pcie *rockchip)
+{
+ u32 status;
+
+ status = rockchip_pcie_read(rockchip, PCIE_EP_CONFIG_LCS);
+ status |= PCI_EXP_LNKCTL_RL;
+ rockchip_pcie_write(rockchip, status, PCIE_EP_CONFIG_LCS);
+}
+
+static bool rockchip_pcie_ep_link_up(struct rockchip_pcie *rockchip)
+{
+ u32 val = rockchip_pcie_read(rockchip, PCIE_CLIENT_BASIC_STATUS1);
+
+ return PCIE_LINK_UP(val);
+}
+
+static void rockchip_pcie_ep_link_training(struct work_struct *work)
+{
+ struct rockchip_pcie_ep *ep =
+ container_of(work, struct rockchip_pcie_ep, link_training.work);
+ struct rockchip_pcie *rockchip = &ep->rockchip;
+ struct device *dev = rockchip->dev;
+ u32 val;
+ int ret;
+
+ /* Enable Gen1 training and wait for its completion */
+ ret = readl_poll_timeout(rockchip->apb_base + PCIE_CORE_CTRL,
+ val, PCIE_LINK_TRAINING_DONE(val), 50,
+ LINK_TRAIN_TIMEOUT);
+ if (ret)
+ goto again;
+
+ /* Make sure that the link is up */
+ ret = readl_poll_timeout(rockchip->apb_base + PCIE_CLIENT_BASIC_STATUS1,
+ val, PCIE_LINK_UP(val), 50,
+ LINK_TRAIN_TIMEOUT);
+ if (ret)
+ goto again;
+
+ /* Check the current speed */
+ val = rockchip_pcie_read(rockchip, PCIE_CORE_CTRL);
+ if (!PCIE_LINK_IS_GEN2(val) && rockchip->link_gen == 2) {
+ /* Enable retrain for gen2 */
+ rockchip_pcie_ep_retrain_link(rockchip);
+ readl_poll_timeout(rockchip->apb_base + PCIE_CORE_CTRL,
+ val, PCIE_LINK_IS_GEN2(val), 50,
+ LINK_TRAIN_TIMEOUT);
+ }
+
+ /* Check again that the link is up */
+ if (!rockchip_pcie_ep_link_up(rockchip))
+ goto again;
+
+ val = rockchip_pcie_read(rockchip, PCIE_CLIENT_BASIC_STATUS0);
+ dev_info(dev,
+ "Link UP (Negociated speed: %sGT/s, width: x%lu)\n",
+ (val & PCIE_CLIENT_NEG_LINK_SPEED) ? "5" : "2.5",
+ ((val & PCIE_CLIENT_NEG_LINK_WIDTH_MASK) >>
+ PCIE_CLIENT_NEG_LINK_WIDTH_SHIFT) << 1);
+
+ /* Notify the function */
+ pci_epc_linkup(ep->epc);
+
+ return;
+
+again:
+ schedule_delayed_work(&ep->link_training, msecs_to_jiffies(5));
+}
+
static const struct pci_epc_features rockchip_pcie_epc_features = {
- .linkup_notifier = false,
+ .linkup_notifier = true,
.msi_capable = true,
.msix_capable = false,
.align = ROCKCHIP_PCIE_AT_SIZE_ALIGN,
@@ -644,6 +720,7 @@ static int rockchip_pcie_ep_probe(struct platform_device *pdev)
rockchip = &ep->rockchip;
rockchip->is_rc = false;
rockchip->dev = dev;
+ INIT_DELAYED_WORK(&ep->link_training, rockchip_pcie_ep_link_training);
epc = devm_pci_epc_create(dev, &rockchip_pcie_epc_ops);
if (IS_ERR(epc)) {
diff --git a/drivers/pci/controller/pcie-rockchip.h b/drivers/pci/controller/pcie-rockchip.h
index 0263f158ee8d..3963b7097a91 100644
--- a/drivers/pci/controller/pcie-rockchip.h
+++ b/drivers/pci/controller/pcie-rockchip.h
@@ -26,6 +26,7 @@
#define MAX_LANE_NUM 4
#define MAX_REGION_LIMIT 32
#define MIN_EP_APERTURE 28
+#define LINK_TRAIN_TIMEOUT (5000 * USEC_PER_MSEC)
#define PCIE_CLIENT_BASE 0x0
#define PCIE_CLIENT_CONFIG (PCIE_CLIENT_BASE + 0x00)
@@ -50,6 +51,10 @@
#define PCIE_CLIENT_DEBUG_LTSSM_MASK GENMASK(5, 0)
#define PCIE_CLIENT_DEBUG_LTSSM_L1 0x18
#define PCIE_CLIENT_DEBUG_LTSSM_L2 0x19
+#define PCIE_CLIENT_BASIC_STATUS0 (PCIE_CLIENT_BASE + 0x44)
+#define PCIE_CLIENT_NEG_LINK_WIDTH_MASK GENMASK(7, 6)
+#define PCIE_CLIENT_NEG_LINK_WIDTH_SHIFT 6
+#define PCIE_CLIENT_NEG_LINK_SPEED BIT(5)
#define PCIE_CLIENT_BASIC_STATUS1 (PCIE_CLIENT_BASE + 0x48)
#define PCIE_CLIENT_LINK_STATUS_UP 0x00300000
#define PCIE_CLIENT_LINK_STATUS_MASK 0x00300000
@@ -87,6 +92,8 @@
#define PCIE_CORE_CTRL_MGMT_BASE 0x900000
#define PCIE_CORE_CTRL (PCIE_CORE_CTRL_MGMT_BASE + 0x000)
+#define PCIE_CORE_PL_CONF_LS_MASK 0x00000001
+#define PCIE_CORE_PL_CONF_LS_READY 0x00000001
#define PCIE_CORE_PL_CONF_SPEED_5G 0x00000008
#define PCIE_CORE_PL_CONF_SPEED_MASK 0x00000018
#define PCIE_CORE_PL_CONF_LANE_MASK 0x00000006
@@ -144,6 +151,7 @@
#define PCIE_RC_CONFIG_BASE 0xa00000
#define PCIE_EP_CONFIG_BASE 0xa00000
#define PCIE_EP_CONFIG_DID_VID (PCIE_EP_CONFIG_BASE + 0x00)
+#define PCIE_EP_CONFIG_LCS (PCIE_EP_CONFIG_BASE + 0xd0)
#define PCIE_RC_CONFIG_RID_CCR (PCIE_RC_CONFIG_BASE + 0x08)
#define PCIE_RC_CONFIG_DCR (PCIE_RC_CONFIG_BASE + 0xc4)
#define PCIE_RC_CONFIG_DCR_CSPL_SHIFT 18
@@ -155,6 +163,7 @@
#define PCIE_RC_CONFIG_LINK_CAP (PCIE_RC_CONFIG_BASE + 0xcc)
#define PCIE_RC_CONFIG_LINK_CAP_L0S BIT(10)
#define PCIE_RC_CONFIG_LCS (PCIE_RC_CONFIG_BASE + 0xd0)
+#define PCIE_EP_CONFIG_LCS (PCIE_EP_CONFIG_BASE + 0xd0)
#define PCIE_RC_CONFIG_L1_SUBSTATE_CTRL2 (PCIE_RC_CONFIG_BASE + 0x90c)
#define PCIE_RC_CONFIG_THP_CAP (PCIE_RC_CONFIG_BASE + 0x274)
#define PCIE_RC_CONFIG_THP_CAP_NEXT_MASK GENMASK(31, 20)
@@ -192,6 +201,8 @@
#define ROCKCHIP_VENDOR_ID 0x1d87
#define PCIE_LINK_IS_L2(x) \
(((x) & PCIE_CLIENT_DEBUG_LTSSM_MASK) == PCIE_CLIENT_DEBUG_LTSSM_L2)
+#define PCIE_LINK_TRAINING_DONE(x) \
+ (((x) & PCIE_CORE_PL_CONF_LS_MASK) == PCIE_CORE_PL_CONF_LS_READY)
#define PCIE_LINK_UP(x) \
(((x) & PCIE_CLIENT_LINK_STATUS_MASK) == PCIE_CLIENT_LINK_STATUS_UP)
#define PCIE_LINK_IS_GEN2(x) \
--
2.44.0
_______________________________________________
Linux-rockchip mailing list
Linux-rockchip@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-rockchip
WARNING: multiple messages have this Message-ID (diff)
From: Damien Le Moal <dlemoal@kernel.org>
To: "Manivannan Sadhasivam" <manivannan.sadhasivam@linaro.org>,
"Lorenzo Pieralisi" <lpieralisi@kernel.org>,
"Kishon Vijay Abraham I" <kishon@kernel.org>,
"Shawn Lin" <shawn.lin@rock-chips.com>,
"Krzysztof Wilczyński" <kw@linux.com>,
"Bjorn Helgaas" <bhelgaas@google.com>,
"Heiko Stuebner" <heiko@sntech.de>,
linux-pci@vger.kernel.org, "Rob Herring" <robh@kernel.org>,
"Krzysztof Kozlowski" <krzysztof.kozlowski+dt@linaro.org>,
"Conor Dooley" <conor+dt@kernel.org>,
devicetree@vger.kernel.org
Cc: linux-rockchip@lists.infradead.org,
linux-arm-kernel@lists.infradead.org,
Rick Wertenbroek <rick.wertenbroek@gmail.com>,
Wilfred Mallawa <wilfred.mallawa@wdc.com>,
Niklas Cassel <cassel@kernel.org>
Subject: [PATCH v2 16/18] PCI: rockchip-ep: Improve link training
Date: Sat, 30 Mar 2024 13:19:26 +0900 [thread overview]
Message-ID: <20240330041928.1555578-17-dlemoal@kernel.org> (raw)
In-Reply-To: <20240330041928.1555578-1-dlemoal@kernel.org>
The Rockchip rk339 technical reference manual describe the endpoint mode
link training process clearly and states that:
Insure link training completion and success by observing link_st field
in PCIe Client BASIC_STATUS1 register change to 2'b11. If both side
support PCIe Gen2 speed, re-train can be Initiated by asserting the
Retrain Link field in Link Control and Status Register. The software
should insure the BASIC_STATUS0[negotiated_speed] changes to "1", that
indicates re-train to Gen2 successfully.
This procedure is very similar to what is done for the root-port mode in
rockchip_pcie_host_init_port().
Implement this link training procedure for the endpoint mode as well.
Given that the rk3399 SoC does not have an interrupt signaling link
status changes, training is implemented as a delayed work which is
rescheduled until the link training completes or the endpoint controller
is stopped. The link training work is first scheduled in
rockchip_pcie_ep_start() when the endpoint function is started. Link
training completion is signaled to the function using pci_epc_linkup().
Accordingly, the linkup_notifier field of the rockchip pci_epc_features
structure is changed to true.
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
---
drivers/pci/controller/pcie-rockchip-ep.c | 79 ++++++++++++++++++++++-
drivers/pci/controller/pcie-rockchip.h | 11 ++++
2 files changed, 89 insertions(+), 1 deletion(-)
diff --git a/drivers/pci/controller/pcie-rockchip-ep.c b/drivers/pci/controller/pcie-rockchip-ep.c
index 2767e8f1771d..4006e7dee71a 100644
--- a/drivers/pci/controller/pcie-rockchip-ep.c
+++ b/drivers/pci/controller/pcie-rockchip-ep.c
@@ -16,6 +16,8 @@
#include <linux/platform_device.h>
#include <linux/pci-epf.h>
#include <linux/sizes.h>
+#include <linux/workqueue.h>
+#include <linux/iopoll.h>
#include "pcie-rockchip.h"
@@ -48,6 +50,7 @@ struct rockchip_pcie_ep {
u64 irq_pci_addr;
u8 irq_pci_fn;
u8 irq_pending;
+ struct delayed_work link_training;
};
static void rockchip_pcie_clear_ep_ob_atu(struct rockchip_pcie *rockchip,
@@ -467,6 +470,8 @@ static int rockchip_pcie_ep_start(struct pci_epc *epc)
PCIE_CLIENT_CONF_ENABLE,
PCIE_CLIENT_CONFIG);
+ schedule_delayed_work(&ep->link_training, 0);
+
return 0;
}
@@ -475,6 +480,8 @@ static void rockchip_pcie_ep_stop(struct pci_epc *epc)
struct rockchip_pcie_ep *ep = epc_get_drvdata(epc);
struct rockchip_pcie *rockchip = &ep->rockchip;
+ cancel_delayed_work_sync(&ep->link_training);
+
/* Stop link training and disable configuration */
rockchip_pcie_write(rockchip,
PCIE_CLIENT_CONF_DISABLE |
@@ -482,8 +489,77 @@ static void rockchip_pcie_ep_stop(struct pci_epc *epc)
PCIE_CLIENT_CONFIG);
}
+static void rockchip_pcie_ep_retrain_link(struct rockchip_pcie *rockchip)
+{
+ u32 status;
+
+ status = rockchip_pcie_read(rockchip, PCIE_EP_CONFIG_LCS);
+ status |= PCI_EXP_LNKCTL_RL;
+ rockchip_pcie_write(rockchip, status, PCIE_EP_CONFIG_LCS);
+}
+
+static bool rockchip_pcie_ep_link_up(struct rockchip_pcie *rockchip)
+{
+ u32 val = rockchip_pcie_read(rockchip, PCIE_CLIENT_BASIC_STATUS1);
+
+ return PCIE_LINK_UP(val);
+}
+
+static void rockchip_pcie_ep_link_training(struct work_struct *work)
+{
+ struct rockchip_pcie_ep *ep =
+ container_of(work, struct rockchip_pcie_ep, link_training.work);
+ struct rockchip_pcie *rockchip = &ep->rockchip;
+ struct device *dev = rockchip->dev;
+ u32 val;
+ int ret;
+
+ /* Enable Gen1 training and wait for its completion */
+ ret = readl_poll_timeout(rockchip->apb_base + PCIE_CORE_CTRL,
+ val, PCIE_LINK_TRAINING_DONE(val), 50,
+ LINK_TRAIN_TIMEOUT);
+ if (ret)
+ goto again;
+
+ /* Make sure that the link is up */
+ ret = readl_poll_timeout(rockchip->apb_base + PCIE_CLIENT_BASIC_STATUS1,
+ val, PCIE_LINK_UP(val), 50,
+ LINK_TRAIN_TIMEOUT);
+ if (ret)
+ goto again;
+
+ /* Check the current speed */
+ val = rockchip_pcie_read(rockchip, PCIE_CORE_CTRL);
+ if (!PCIE_LINK_IS_GEN2(val) && rockchip->link_gen == 2) {
+ /* Enable retrain for gen2 */
+ rockchip_pcie_ep_retrain_link(rockchip);
+ readl_poll_timeout(rockchip->apb_base + PCIE_CORE_CTRL,
+ val, PCIE_LINK_IS_GEN2(val), 50,
+ LINK_TRAIN_TIMEOUT);
+ }
+
+ /* Check again that the link is up */
+ if (!rockchip_pcie_ep_link_up(rockchip))
+ goto again;
+
+ val = rockchip_pcie_read(rockchip, PCIE_CLIENT_BASIC_STATUS0);
+ dev_info(dev,
+ "Link UP (Negociated speed: %sGT/s, width: x%lu)\n",
+ (val & PCIE_CLIENT_NEG_LINK_SPEED) ? "5" : "2.5",
+ ((val & PCIE_CLIENT_NEG_LINK_WIDTH_MASK) >>
+ PCIE_CLIENT_NEG_LINK_WIDTH_SHIFT) << 1);
+
+ /* Notify the function */
+ pci_epc_linkup(ep->epc);
+
+ return;
+
+again:
+ schedule_delayed_work(&ep->link_training, msecs_to_jiffies(5));
+}
+
static const struct pci_epc_features rockchip_pcie_epc_features = {
- .linkup_notifier = false,
+ .linkup_notifier = true,
.msi_capable = true,
.msix_capable = false,
.align = ROCKCHIP_PCIE_AT_SIZE_ALIGN,
@@ -644,6 +720,7 @@ static int rockchip_pcie_ep_probe(struct platform_device *pdev)
rockchip = &ep->rockchip;
rockchip->is_rc = false;
rockchip->dev = dev;
+ INIT_DELAYED_WORK(&ep->link_training, rockchip_pcie_ep_link_training);
epc = devm_pci_epc_create(dev, &rockchip_pcie_epc_ops);
if (IS_ERR(epc)) {
diff --git a/drivers/pci/controller/pcie-rockchip.h b/drivers/pci/controller/pcie-rockchip.h
index 0263f158ee8d..3963b7097a91 100644
--- a/drivers/pci/controller/pcie-rockchip.h
+++ b/drivers/pci/controller/pcie-rockchip.h
@@ -26,6 +26,7 @@
#define MAX_LANE_NUM 4
#define MAX_REGION_LIMIT 32
#define MIN_EP_APERTURE 28
+#define LINK_TRAIN_TIMEOUT (5000 * USEC_PER_MSEC)
#define PCIE_CLIENT_BASE 0x0
#define PCIE_CLIENT_CONFIG (PCIE_CLIENT_BASE + 0x00)
@@ -50,6 +51,10 @@
#define PCIE_CLIENT_DEBUG_LTSSM_MASK GENMASK(5, 0)
#define PCIE_CLIENT_DEBUG_LTSSM_L1 0x18
#define PCIE_CLIENT_DEBUG_LTSSM_L2 0x19
+#define PCIE_CLIENT_BASIC_STATUS0 (PCIE_CLIENT_BASE + 0x44)
+#define PCIE_CLIENT_NEG_LINK_WIDTH_MASK GENMASK(7, 6)
+#define PCIE_CLIENT_NEG_LINK_WIDTH_SHIFT 6
+#define PCIE_CLIENT_NEG_LINK_SPEED BIT(5)
#define PCIE_CLIENT_BASIC_STATUS1 (PCIE_CLIENT_BASE + 0x48)
#define PCIE_CLIENT_LINK_STATUS_UP 0x00300000
#define PCIE_CLIENT_LINK_STATUS_MASK 0x00300000
@@ -87,6 +92,8 @@
#define PCIE_CORE_CTRL_MGMT_BASE 0x900000
#define PCIE_CORE_CTRL (PCIE_CORE_CTRL_MGMT_BASE + 0x000)
+#define PCIE_CORE_PL_CONF_LS_MASK 0x00000001
+#define PCIE_CORE_PL_CONF_LS_READY 0x00000001
#define PCIE_CORE_PL_CONF_SPEED_5G 0x00000008
#define PCIE_CORE_PL_CONF_SPEED_MASK 0x00000018
#define PCIE_CORE_PL_CONF_LANE_MASK 0x00000006
@@ -144,6 +151,7 @@
#define PCIE_RC_CONFIG_BASE 0xa00000
#define PCIE_EP_CONFIG_BASE 0xa00000
#define PCIE_EP_CONFIG_DID_VID (PCIE_EP_CONFIG_BASE + 0x00)
+#define PCIE_EP_CONFIG_LCS (PCIE_EP_CONFIG_BASE + 0xd0)
#define PCIE_RC_CONFIG_RID_CCR (PCIE_RC_CONFIG_BASE + 0x08)
#define PCIE_RC_CONFIG_DCR (PCIE_RC_CONFIG_BASE + 0xc4)
#define PCIE_RC_CONFIG_DCR_CSPL_SHIFT 18
@@ -155,6 +163,7 @@
#define PCIE_RC_CONFIG_LINK_CAP (PCIE_RC_CONFIG_BASE + 0xcc)
#define PCIE_RC_CONFIG_LINK_CAP_L0S BIT(10)
#define PCIE_RC_CONFIG_LCS (PCIE_RC_CONFIG_BASE + 0xd0)
+#define PCIE_EP_CONFIG_LCS (PCIE_EP_CONFIG_BASE + 0xd0)
#define PCIE_RC_CONFIG_L1_SUBSTATE_CTRL2 (PCIE_RC_CONFIG_BASE + 0x90c)
#define PCIE_RC_CONFIG_THP_CAP (PCIE_RC_CONFIG_BASE + 0x274)
#define PCIE_RC_CONFIG_THP_CAP_NEXT_MASK GENMASK(31, 20)
@@ -192,6 +201,8 @@
#define ROCKCHIP_VENDOR_ID 0x1d87
#define PCIE_LINK_IS_L2(x) \
(((x) & PCIE_CLIENT_DEBUG_LTSSM_MASK) == PCIE_CLIENT_DEBUG_LTSSM_L2)
+#define PCIE_LINK_TRAINING_DONE(x) \
+ (((x) & PCIE_CORE_PL_CONF_LS_MASK) == PCIE_CORE_PL_CONF_LS_READY)
#define PCIE_LINK_UP(x) \
(((x) & PCIE_CLIENT_LINK_STATUS_MASK) == PCIE_CLIENT_LINK_STATUS_UP)
#define PCIE_LINK_IS_GEN2(x) \
--
2.44.0
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next prev parent reply other threads:[~2024-03-30 4:20 UTC|newest]
Thread overview: 162+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-03-30 4:19 [PATCH v2 00/18] Improve PCI memory mapping API Damien Le Moal
2024-03-30 4:19 ` Damien Le Moal
2024-03-30 4:19 ` Damien Le Moal
2024-03-30 4:19 ` [PATCH v2 01/18] PCI: endpoint: Introduce pci_epc_function_is_valid() Damien Le Moal
2024-03-30 4:19 ` Damien Le Moal
2024-03-30 4:19 ` Damien Le Moal
2024-04-03 6:46 ` Manivannan Sadhasivam
2024-04-03 6:46 ` Manivannan Sadhasivam
2024-04-03 6:46 ` Manivannan Sadhasivam
2024-04-05 13:33 ` Niklas Cassel
2024-04-05 13:33 ` Niklas Cassel
2024-04-05 13:33 ` Niklas Cassel
2024-03-30 4:19 ` [PATCH v2 02/18] PCI: endpoint: Introduce pci_epc_map_align() Damien Le Moal
2024-03-30 4:19 ` Damien Le Moal
2024-03-30 4:19 ` Damien Le Moal
2024-04-03 7:45 ` Manivannan Sadhasivam
2024-04-03 7:45 ` Manivannan Sadhasivam
2024-04-03 7:45 ` Manivannan Sadhasivam
2024-04-03 7:54 ` Damien Le Moal
2024-04-03 7:54 ` Damien Le Moal
2024-04-03 7:54 ` Damien Le Moal
2024-04-03 9:21 ` Manivannan Sadhasivam
2024-04-03 9:21 ` Manivannan Sadhasivam
2024-04-03 9:21 ` Manivannan Sadhasivam
2024-04-03 12:33 ` Kishon Vijay Abraham I
2024-04-03 12:33 ` Kishon Vijay Abraham I
2024-04-03 12:33 ` Kishon Vijay Abraham I
2024-04-04 2:43 ` Damien Le Moal
2024-04-04 2:43 ` Damien Le Moal
2024-04-04 2:43 ` Damien Le Moal
2024-04-05 12:20 ` Niklas Cassel
2024-04-05 12:20 ` Niklas Cassel
2024-04-05 12:20 ` Niklas Cassel
2024-04-05 12:43 ` Damien Le Moal
2024-04-05 12:43 ` Damien Le Moal
2024-04-05 12:43 ` Damien Le Moal
2024-04-05 15:18 ` Niklas Cassel
2024-04-05 15:18 ` Niklas Cassel
2024-04-05 15:18 ` Niklas Cassel
2024-04-10 11:57 ` Kishon Vijay Abraham I
2024-04-10 11:57 ` Kishon Vijay Abraham I
2024-04-10 11:57 ` Kishon Vijay Abraham I
2024-04-05 8:38 ` Dan Carpenter
2024-04-05 8:38 ` Dan Carpenter
2024-04-05 8:38 ` Dan Carpenter
2024-03-30 4:19 ` [PATCH v2 03/18] PCI: endpoint: Introduce pci_epc_mem_map()/unmap() Damien Le Moal
2024-03-30 4:19 ` Damien Le Moal
2024-03-30 4:19 ` Damien Le Moal
2024-04-03 9:48 ` Manivannan Sadhasivam
2024-04-03 9:48 ` Manivannan Sadhasivam
2024-04-03 9:48 ` Manivannan Sadhasivam
2024-04-05 14:10 ` Niklas Cassel
2024-04-05 14:10 ` Niklas Cassel
2024-04-05 14:10 ` Niklas Cassel
2024-03-30 4:19 ` [PATCH v2 04/18] PCI: endpoint: test: Use pci_epc_mem_map/unmap() Damien Le Moal
2024-03-30 4:19 ` Damien Le Moal
2024-03-30 4:19 ` Damien Le Moal
2024-04-05 13:37 ` Niklas Cassel
2024-04-05 13:37 ` Niklas Cassel
2024-04-05 13:37 ` Niklas Cassel
2024-03-30 4:19 ` [PATCH v2 05/18] PCI: endpoint: test: Synchronously cancel command handler work Damien Le Moal
2024-03-30 4:19 ` Damien Le Moal
2024-03-30 4:19 ` Damien Le Moal
2024-04-03 7:47 ` Manivannan Sadhasivam
2024-04-03 7:47 ` Manivannan Sadhasivam
2024-04-03 7:47 ` Manivannan Sadhasivam
2024-04-05 13:41 ` Niklas Cassel
2024-04-05 13:41 ` Niklas Cassel
2024-04-05 13:41 ` Niklas Cassel
2024-03-30 4:19 ` [PATCH v2 06/18] PCI: endpoint: test: Implement link_down event operation Damien Le Moal
2024-03-30 4:19 ` Damien Le Moal
2024-03-30 4:19 ` Damien Le Moal
2024-04-03 7:48 ` Manivannan Sadhasivam
2024-04-03 7:48 ` Manivannan Sadhasivam
2024-04-03 7:48 ` Manivannan Sadhasivam
2024-04-05 13:39 ` Niklas Cassel
2024-04-05 13:39 ` Niklas Cassel
2024-04-05 13:39 ` Niklas Cassel
2024-04-06 2:24 ` Manivannan Sadhasivam
2024-04-06 2:24 ` Manivannan Sadhasivam
2024-04-06 2:24 ` Manivannan Sadhasivam
2024-03-30 4:19 ` [PATCH v2 07/18] PCI: rockchip-ep: Fix address translation unit programming Damien Le Moal
2024-03-30 4:19 ` Damien Le Moal
2024-03-30 4:19 ` Damien Le Moal
2024-03-30 4:19 ` [PATCH v2 08/18] PCI: rockchip-ep: Use a macro to define EP controller .align feature Damien Le Moal
2024-03-30 4:19 ` Damien Le Moal
2024-03-30 4:19 ` Damien Le Moal
2024-03-30 4:19 ` [PATCH v2 09/18] PCI: rockchip-ep: Improve rockchip_pcie_ep_unmap_addr() Damien Le Moal
2024-03-30 4:19 ` Damien Le Moal
2024-03-30 4:19 ` Damien Le Moal
2024-03-30 4:19 ` [PATCH v2 10/18] PCI: rockchip-ep: Improve rockchip_pcie_ep_map_addr() Damien Le Moal
2024-03-30 4:19 ` Damien Le Moal
2024-03-30 4:19 ` Damien Le Moal
2024-03-30 4:19 ` [PATCH v2 11/18] PCI: rockchip-ep: Implement the map_align endpoint controller operation Damien Le Moal
2024-03-30 4:19 ` Damien Le Moal
2024-03-30 4:19 ` Damien Le Moal
2024-03-30 4:19 ` [PATCH v2 12/18] PCI: rockchip-ep: Refactor rockchip_pcie_ep_probe() memory allocations Damien Le Moal
2024-03-30 4:19 ` Damien Le Moal
2024-03-30 4:19 ` Damien Le Moal
2024-03-30 4:19 ` [PATCH v2 13/18] PCI: rockchip-ep: Refactor rockchip_pcie_ep_probe() MSI-X hiding Damien Le Moal
2024-03-30 4:19 ` Damien Le Moal
2024-03-30 4:19 ` Damien Le Moal
2024-03-30 4:19 ` [PATCH v2 14/18] PCI: rockchip-ep: Refactor endpoint link training enable Damien Le Moal
2024-03-30 4:19 ` Damien Le Moal
2024-03-30 4:19 ` Damien Le Moal
2024-03-30 4:19 ` [PATCH v2 15/18] PCI: rockship-ep: Introduce rockchip_pcie_ep_stop() Damien Le Moal
2024-03-30 4:19 ` Damien Le Moal
2024-03-30 4:19 ` Damien Le Moal
2024-03-30 4:19 ` Damien Le Moal [this message]
2024-03-30 4:19 ` [PATCH v2 16/18] PCI: rockchip-ep: Improve link training Damien Le Moal
2024-03-30 4:19 ` Damien Le Moal
2024-04-03 11:54 ` Rick Wertenbroek
2024-04-03 11:54 ` Rick Wertenbroek
2024-04-03 11:54 ` Rick Wertenbroek
2024-03-30 4:19 ` [PATCH v2 17/18] dt-bindings: pci: rockchip,rk3399-pcie-ep: Add ep-gpios property Damien Le Moal
2024-03-30 4:19 ` Damien Le Moal
2024-03-30 4:19 ` Damien Le Moal
2024-03-30 9:16 ` Krzysztof Kozlowski
2024-03-30 9:16 ` Krzysztof Kozlowski
2024-03-30 9:16 ` Krzysztof Kozlowski
2024-03-31 23:06 ` Damien Le Moal
2024-03-31 23:06 ` Damien Le Moal
2024-03-31 23:06 ` Damien Le Moal
2024-04-01 9:57 ` Krzysztof Kozlowski
2024-04-01 9:57 ` Krzysztof Kozlowski
2024-04-01 9:57 ` Krzysztof Kozlowski
2024-04-01 23:36 ` Damien Le Moal
2024-04-01 23:36 ` Damien Le Moal
2024-04-01 23:36 ` Damien Le Moal
2024-04-02 7:33 ` Krzysztof Kozlowski
2024-04-02 7:33 ` Krzysztof Kozlowski
2024-04-02 7:33 ` Krzysztof Kozlowski
2024-04-02 7:38 ` Damien Le Moal
2024-04-02 7:38 ` Damien Le Moal
2024-04-02 7:38 ` Damien Le Moal
2024-04-02 7:55 ` Damien Le Moal
2024-04-02 7:55 ` Damien Le Moal
2024-04-02 7:55 ` Damien Le Moal
2024-04-02 18:10 ` Krzysztof Kozlowski
2024-04-02 18:10 ` Krzysztof Kozlowski
2024-04-02 18:10 ` Krzysztof Kozlowski
2024-04-02 23:23 ` Damien Le Moal
2024-04-02 23:23 ` Damien Le Moal
2024-04-02 23:23 ` Damien Le Moal
2024-04-02 7:38 ` Damien Le Moal
2024-04-02 7:38 ` Damien Le Moal
2024-04-02 7:38 ` Damien Le Moal
2024-03-30 4:19 ` [PATCH v2 18/18] PCI: rockchip-ep: Handle PERST# signal in endpoint mode Damien Le Moal
2024-03-30 4:19 ` Damien Le Moal
2024-03-30 4:19 ` Damien Le Moal
2024-04-02 12:36 ` [PATCH v2 00/18] Improve PCI memory mapping API Rick Wertenbroek
2024-04-02 12:36 ` Rick Wertenbroek
2024-04-02 12:36 ` Rick Wertenbroek
2024-04-03 7:50 ` Manivannan Sadhasivam
2024-04-03 7:50 ` Manivannan Sadhasivam
2024-04-03 7:50 ` Manivannan Sadhasivam
2024-04-03 7:58 ` Damien Le Moal
2024-04-03 7:58 ` Damien Le Moal
2024-04-03 7:58 ` Damien Le Moal
2024-04-03 9:25 ` Manivannan Sadhasivam
2024-04-03 9:25 ` Manivannan Sadhasivam
2024-04-03 9:25 ` Manivannan Sadhasivam
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