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Quality Improvements for Rockchip-IP PCIe

RFC PATCH Superseded Geraldo Nascimento 2 participants 8 messages Jun 13, 2025 – Jun 14, 2025

Subsystems (5)

v3 of 9 Superseded Latest is v9 →

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#0 lore raw

v3 cover Quality Improvements for Rockchip-IP PCIe

During a 30-day debugging-run fighting quirky PCIe devices on RK3399 some quality improvements began to take form and this is my attempt at upstreaming it. It will ensure maximum chance of retraining to Gen2 5.0GT/s, on all four lanes and plus if anybody is debugging the PHY they'll now get real values from TEST_I[3:0] for every TEST_ADDR[4:0] without risk of locking up kernel like with present broken async strobe TEST_WRITE.

---
V2 -> V3: correctly clean-up with standard PCIe defines as per Bjorn's suggestion
V1 -> V2: use standard PCIe defines as suggested by Bjorn

Geraldo Nascimento (5):
PCI: rockchip-host: Use standard PCIe defines
PCI: rockchip: Drop unused custom registers and bitfields
PCI: rockchip-host: Set Target Link Speed before retraining
phy: rockchip-pcie: Enable all four lanes
phy: rockchip-pcie: Adjust read mask and write

 drivers/pci/controller/pcie-rockchip-host.c | 48 +++++++++++----------
 drivers/pci/controller/pcie-rockchip.h      | 11 +----
 drivers/phy/rockchip/phy-rockchip-pcie.c    | 16 ++++---
 3 files changed, 36 insertions(+), 39 deletions(-)
Signature · 1 line
2.49.0
#1 lore raw

RFC PATCH v3 1/5 PCI: rockchip-host: Use standard PCIe defines

Current code uses custom-defined register offsets and bitfields for standard PCIe registers. Change to using standard PCIe defines.

---
 drivers/pci/controller/pcie-rockchip-host.c | 44 ++++++++++-----------
 1 file changed, 22 insertions(+), 22 deletions(-)
drivers/pci/controller/pcie-rockchip-host.c +22 -22
index b9e7a8710cf0..65653218b9ab 100644
@@ -40,18 +40,18 @@ static void rockchip_pcie_enable_bw_int(struct rockchip_pcie *rockchip)
 {
 	u32 status;
 
-	status = rockchip_pcie_read(rockchip, PCIE_RC_CONFIG_LCS);
+	status = rockchip_pcie_read(rockchip, PCIE_RC_CONFIG_CR + PCI_EXP_LNKCTL);
 	status |= (PCI_EXP_LNKCTL_LBMIE | PCI_EXP_LNKCTL_LABIE);
-	rockchip_pcie_write(rockchip, status, PCIE_RC_CONFIG_LCS);
+	rockchip_pcie_write(rockchip, status, PCIE_RC_CONFIG_CR + PCI_EXP_LNKCTL);
 }
 
 static void rockchip_pcie_clr_bw_int(struct rockchip_pcie *rockchip)
 {
 	u32 status;
 
-	status = rockchip_pcie_read(rockchip, PCIE_RC_CONFIG_LCS);
+	status = rockchip_pcie_read(rockchip, PCIE_RC_CONFIG_CR + PCI_EXP_LNKCTL);
 	status |= (PCI_EXP_LNKSTA_LBMS | PCI_EXP_LNKSTA_LABS) << 16;
-	rockchip_pcie_write(rockchip, status, PCIE_RC_CONFIG_LCS);
+	rockchip_pcie_write(rockchip, status, PCIE_RC_CONFIG_CR + PCI_EXP_LNKCTL);
 }
 
 static void rockchip_pcie_update_txcredit_mui(struct rockchip_pcie *rockchip)
@@ -269,7 +269,7 @@ static void rockchip_pcie_set_power_limit(struct rockchip_pcie *rockchip)
 	scale = 3; /* 0.001x */
 	curr = curr / 1000; /* convert to mA */
 	power = (curr * 3300) / 1000; /* milliwatt */
-	while (power > PCIE_RC_CONFIG_DCR_CSPL_LIMIT) {
+	while (power > FIELD_MAX(PCI_EXP_DEVCAP_PWR_VAL)) {
 		if (!scale) {
 			dev_warn(rockchip->dev, "invalid power supply\n");
 			return;
@@ -278,10 +278,10 @@ static void rockchip_pcie_set_power_limit(struct rockchip_pcie *rockchip)
 		power = power / 10;
 	}
 
-	status = rockchip_pcie_read(rockchip, PCIE_RC_CONFIG_DCR);
-	status |= (power << PCIE_RC_CONFIG_DCR_CSPL_SHIFT) |
-		  (scale << PCIE_RC_CONFIG_DCR_CPLS_SHIFT);
-	rockchip_pcie_write(rockchip, status, PCIE_RC_CONFIG_DCR);
+	status = rockchip_pcie_read(rockchip, PCIE_RC_CONFIG_CR + PCI_EXP_DEVCAP);
+	status |= FIELD_PREP(PCI_EXP_DEVCAP_PWR_VAL, power);
+	status |= FIELD_PREP(PCI_EXP_DEVCAP_PWR_SCL, scale);
+	rockchip_pcie_write(rockchip, status, PCIE_RC_CONFIG_CR + PCI_EXP_DEVCAP);
 }
 
 /**
@@ -309,14 +309,14 @@ static int rockchip_pcie_host_init_port(struct rockchip_pcie *rockchip)
 	rockchip_pcie_set_power_limit(rockchip);
 
 	/* Set RC's clock architecture as common clock */
-	status = rockchip_pcie_read(rockchip, PCIE_RC_CONFIG_LCS);
+	status = rockchip_pcie_read(rockchip, PCIE_RC_CONFIG_CR + PCI_EXP_LNKCTL);
 	status |= PCI_EXP_LNKSTA_SLC << 16;
-	rockchip_pcie_write(rockchip, status, PCIE_RC_CONFIG_LCS);
+	rockchip_pcie_write(rockchip, status, PCIE_RC_CONFIG_CR + PCI_EXP_LNKCTL);
 
 	/* Set RC's RCB to 128 */
-	status = rockchip_pcie_read(rockchip, PCIE_RC_CONFIG_LCS);
+	status = rockchip_pcie_read(rockchip, PCIE_RC_CONFIG_CR + PCI_EXP_LNKCTL);
 	status |= PCI_EXP_LNKCTL_RCB;
-	rockchip_pcie_write(rockchip, status, PCIE_RC_CONFIG_LCS);
+	rockchip_pcie_write(rockchip, status, PCIE_RC_CONFIG_CR + PCI_EXP_LNKCTL);
 
 	/* Enable Gen1 training */
 	rockchip_pcie_write(rockchip, PCIE_CLIENT_LINK_TRAIN_ENABLE,
@@ -341,9 +341,9 @@ static int rockchip_pcie_host_init_port(struct rockchip_pcie *rockchip)
 		 * Enable retrain for gen2. This should be configured only after
 		 * gen1 finished.
 		 */
-		status = rockchip_pcie_read(rockchip, PCIE_RC_CONFIG_LCS);
+		status = rockchip_pcie_read(rockchip, PCIE_RC_CONFIG_CR + PCI_EXP_LNKCTL);
 		status |= PCI_EXP_LNKCTL_RL;
-		rockchip_pcie_write(rockchip, status, PCIE_RC_CONFIG_LCS);
+		rockchip_pcie_write(rockchip, status, PCIE_RC_CONFIG_CR + PCI_EXP_LNKCTL);
 
 		err = readl_poll_timeout(rockchip->apb_base + PCIE_CORE_CTRL,
 					 status, PCIE_LINK_IS_GEN2(status), 20,
@@ -380,15 +380,15 @@ static int rockchip_pcie_host_init_port(struct rockchip_pcie *rockchip)
 
 	/* Clear L0s from RC's link cap */
 	if (of_property_read_bool(dev->of_node, "aspm-no-l0s")) {
-		status = rockchip_pcie_read(rockchip, PCIE_RC_CONFIG_LINK_CAP);
-		status &= ~PCIE_RC_CONFIG_LINK_CAP_L0S;
-		rockchip_pcie_write(rockchip, status, PCIE_RC_CONFIG_LINK_CAP);
+		status = rockchip_pcie_read(rockchip, PCIE_RC_CONFIG_CR + PCI_EXP_LNKCAP);
+		status &= ~PCI_EXP_LNKCAP_ASPM_L0S;
+		rockchip_pcie_write(rockchip, status, PCIE_RC_CONFIG_CR + PCI_EXP_LNKCAP);
 	}
 
-	status = rockchip_pcie_read(rockchip, PCIE_RC_CONFIG_DCSR);
-	status &= ~PCIE_RC_CONFIG_DCSR_MPS_MASK;
-	status |= PCIE_RC_CONFIG_DCSR_MPS_256;
-	rockchip_pcie_write(rockchip, status, PCIE_RC_CONFIG_DCSR);
+	status = rockchip_pcie_read(rockchip, PCIE_RC_CONFIG_CR + PCI_EXP_DEVCTL);
+	status &= ~PCI_EXP_DEVCTL_PAYLOAD;
+	status |= PCI_EXP_DEVCTL_PAYLOAD_256B;
+	rockchip_pcie_write(rockchip, status, PCIE_RC_CONFIG_CR + PCI_EXP_DEVCTL);
 
 	return 0;
 err_power_off_phy:
Signature · 1 line
2.49.0
#2 lore raw

Re: [RFC PATCH v3 1/5] PCI: rockchip-host: Use standard PCIe defines

kernel test robot noticed the following build errors:

Hi Geraldo,

[This is a private test report for your RFC patch.] kernel test robot noticed the following build errors:

[auto build test ERROR on rockchip/for-next]
[also build test ERROR on pci/next pci/for-linus mani-mhi/mhi-next linus/master v6.16-rc1 next-20250613] [If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Geraldo-Nascimento/PCI-rockchip-host-Use-standard-PCIe-defines/20250613-132302
base:   https://git.kernel.org/pub/scm/linux/kernel/git/mmind/linux-rockchip.git for-next
patch link:    https://lore.kernel.org/r/fc88993a561fcc9a9960c038bbc8b0b717924888.1749791474.git.geraldogabriel%40gmail.com
patch subject: [RFC PATCH v3 1/5] PCI: rockchip-host: Use standard PCIe defines
config: s390-randconfig-002-20250614 (https://download.01.org/0day-ci/archive/20250614/[email protected]/config)
compiler: s390-linux-gcc (GCC) 10.5.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250614/[email protected]/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <[email protected]>
| Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/

All errors (new ones prefixed by >>):

drivers/pci/controller/pcie-rockchip-host.c: In function 'rockchip_pcie_enable_bw_int':
drivers/pci/controller/pcie-rockchip-host.c:43:40: error: 'PCIE_RC_CONFIG_CR' undeclared (first use in this function); did you mean 'PCIE_RC_CONFIG_DCR'?

      43 |  status = rockchip_pcie_read(rockchip, PCIE_RC_CONFIG_CR + PCI_EXP_LNKCTL);
         |                                        ^~~~~~~~~~~~~~~~~
         |                                        PCIE_RC_CONFIG_DCR
   drivers/pci/controller/pcie-rockchip-host.c:43:40: note: each undeclared identifier is reported only once for each function it appears in
   drivers/pci/controller/pcie-rockchip-host.c: In function 'rockchip_pcie_clr_bw_int':
   drivers/pci/controller/pcie-rockchip-host.c:52:40: error: 'PCIE_RC_CONFIG_CR' undeclared (first use in this function); did you mean 'PCIE_RC_CONFIG_DCR'?
      52 |  status = rockchip_pcie_read(rockchip, PCIE_RC_CONFIG_CR + PCI_EXP_LNKCTL);
         |                                        ^~~~~~~~~~~~~~~~~
         |                                        PCIE_RC_CONFIG_DCR
   drivers/pci/controller/pcie-rockchip-host.c: In function 'rockchip_pcie_set_power_limit':
>> drivers/pci/controller/pcie-rockchip-host.c:272:17: error: implicit declaration of function 'FIELD_MAX' [-Werror=implicit-function-declaration]
     272 |  while (power > FIELD_MAX(PCI_EXP_DEVCAP_PWR_VAL)) {
         |                 ^~~~~~~~~
   drivers/pci/controller/pcie-rockchip-host.c:281:40: error: 'PCIE_RC_CONFIG_CR' undeclared (first use in this function); did you mean 'PCIE_RC_CONFIG_DCR'?
     281 |  status = rockchip_pcie_read(rockchip, PCIE_RC_CONFIG_CR + PCI_EXP_DEVCAP);
         |                                        ^~~~~~~~~~~~~~~~~
         |                                        PCIE_RC_CONFIG_DCR
>> drivers/pci/controller/pcie-rockchip-host.c:282:12: error: implicit declaration of function 'FIELD_PREP' [-Werror=implicit-function-declaration]
     282 |  status |= FIELD_PREP(PCI_EXP_DEVCAP_PWR_VAL, power);
         |            ^~~~~~~~~~
   drivers/pci/controller/pcie-rockchip-host.c: In function 'rockchip_pcie_host_init_port':
   drivers/pci/controller/pcie-rockchip-host.c:312:40: error: 'PCIE_RC_CONFIG_CR' undeclared (first use in this function); did you mean 'PCIE_RC_CONFIG_DCR'?
     312 |  status = rockchip_pcie_read(rockchip, PCIE_RC_CONFIG_CR + PCI_EXP_LNKCTL);
         |                                        ^~~~~~~~~~~~~~~~~
         |                                        PCIE_RC_CONFIG_DCR

cc1: some warnings being treated as errors

vim +/FIELD_MAX +272 drivers/pci/controller/pcie-rockchip-host.c

250
251 static void rockchip_pcie_set_power_limit(struct rockchip_pcie *rockchip)
252 {
253 int curr;
254 u32 status, scale, power;
255
256 if (IS_ERR(rockchip->vpcie3v3))
257 return;
258
259 /*
260 * Set RC's captured slot power limit and scale if
261 * vpcie3v3 available. The default values are both zero
262 * which means the software should set these two according
263 * to the actual power supply.
264 */
265 curr = regulator_get_current_limit(rockchip->vpcie3v3);
266 if (curr <= 0)
267 return;
268
269 scale = 3; /* 0.001x */
270 curr = curr / 1000; /* convert to mA */
271 power = (curr * 3300) / 1000; /* milliwatt */

 > 272		while (power > FIELD_MAX(PCI_EXP_DEVCAP_PWR_VAL)) {
   273			if (!scale) {
   274				dev_warn(rockchip->dev, "invalid power supply\n");
   275				return;
   276			}
   277			scale--;
   278			power = power / 10;
   279		}
   280	
   281		status = rockchip_pcie_read(rockchip, PCIE_RC_CONFIG_CR + PCI_EXP_DEVCAP);
 > 282		status |= FIELD_PREP(PCI_EXP_DEVCAP_PWR_VAL, power);

283 status |= FIELD_PREP(PCI_EXP_DEVCAP_PWR_SCL, scale);
284 rockchip_pcie_write(rockchip, status, PCIE_RC_CONFIG_CR + PCI_EXP_DEVCAP);
285 }
286

Signature · 2 lines
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
#3 lore raw

RFC PATCH v3 2/5 PCI: rockchip: Drop unused custom registers and bitfields

In reply to Geraldo Nascimento

Since we are now using standard PCIe defines, drop unused custom-defined ones and instead reference them by offset from Capabilities Register.

---
 drivers/pci/controller/pcie-rockchip.h | 11 +----------
 1 file changed, 1 insertion(+), 10 deletions(-)
drivers/pci/controller/pcie-rockchip.h +1 -10
index 5864a20323f2..f611599988d7 100644
@@ -155,16 +155,7 @@
 #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
-#define   PCIE_RC_CONFIG_DCR_CSPL_LIMIT		0xff
-#define   PCIE_RC_CONFIG_DCR_CPLS_SHIFT		26
-#define PCIE_RC_CONFIG_DCSR		(PCIE_RC_CONFIG_BASE + 0xc8)
-#define   PCIE_RC_CONFIG_DCSR_MPS_MASK		GENMASK(7, 5)
-#define   PCIE_RC_CONFIG_DCSR_MPS_256		(0x1 << 5)
-#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_RC_CONFIG_CR		(PCIE_RC_CONFIG_BASE + 0xc0)
 #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)
Signature · 1 line
2.49.0
#4 lore raw

RFC PATCH v3 3/5 PCI: rockchip-host: Set Target Link Speed before retraining

In reply to Geraldo Nascimento

Current code may fail Gen2 retraining if Target Link Speed is set to 2.5 GT/s in Link Control and Status Register 2. Set it to 5.0 GT/s accordingly.

---
 drivers/pci/controller/pcie-rockchip-host.c | 4 ++++
 1 file changed, 4 insertions(+)
drivers/pci/controller/pcie-rockchip-host.c +4 -0
index 65653218b9ab..68634ae8caaf 100644
@@ -341,6 +341,10 @@ static int rockchip_pcie_host_init_port(struct rockchip_pcie *rockchip)
 		 * Enable retrain for gen2. This should be configured only after
 		 * gen1 finished.
 		 */
+		status = rockchip_pcie_read(rockchip, PCIE_RC_CONFIG_CR + PCI_EXP_LNKCTL2);
+		status |= FIELD_PREP(PCI_EXP_LNKCTL2_TLS, PCI_EXP_LNKCTL2_TLS_5_0GT);
+		rockchip_pcie_write(rockchip, status, PCIE_RC_CONFIG_CR + PCI_EXP_LNKCTL2);
+
 		status = rockchip_pcie_read(rockchip, PCIE_RC_CONFIG_CR + PCI_EXP_LNKCTL);
 		status |= PCI_EXP_LNKCTL_RL;
 		rockchip_pcie_write(rockchip, status, PCIE_RC_CONFIG_CR + PCI_EXP_LNKCTL);
Signature · 1 line
2.49.0
#5 lore raw

Re: [RFC PATCH v3 3/5] PCI: rockchip-host: Set Target Link Speed before retraining

Quoted 14 lines · Geraldo Nascimento

Current code may fail Gen2 retraining if Target Link Speed is set to 2.5 GT/s in Link Control and Status Register 2. Set it to 5.0 GT/s accordingly.

---
 drivers/pci/controller/pcie-rockchip-host.c | 4 ++++
 1 file changed, 4 insertions(+)
drivers/pci/controller/pcie-rockchip-host.c +0 -0
index 65653218b9ab..68634ae8caaf 100644

drivers/pci/controller/pcie-rockchip-host.c static int rockchip_pcie_host_init_port(struct rockchip_pcie *rockchip) · line 345

Quoted 5 lines
drivers/pci/controller/pcie-rockchip-host.c +2 -0
@@ -341,6 +341,10 @@ static int rockchip_pcie_host_init_port(struct rockchip_pcie *rockchip)
 		 * Enable retrain for gen2. This should be configured only after
 		 * gen1 finished.
 		 */
+		status = rockchip_pcie_read(rockchip, PCIE_RC_CONFIG_CR + PCI_EXP_LNKCTL2);
+		status |= FIELD_PREP(PCI_EXP_LNKCTL2_TLS, PCI_EXP_LNKCTL2_TLS_5_0GT);

Although this incidentally "works" for facilitating Gen2 training because mask clears 2.5 GT/s, this will shift the value 0x2 by the mask I think. This is clearly wrong, and instead we should use AND clearing plus OR'ing the 5.0GT/s value.

But I wait until at least Bjorn's review to send v4 with correction.

Geraldo Nascimento

#6 lore raw

RFC PATCH v3 4/5 phy: rockchip-pcie: Enable all four lanes

In reply to Geraldo Nascimento

Current code enables only Lane 0 because pwr_cnt will be incremented on first call to the function. Use for-loop to enable all 4 lanes through GRF.

---
 drivers/phy/rockchip/phy-rockchip-pcie.c | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)
drivers/phy/rockchip/phy-rockchip-pcie.c +7 -5
index bd44af36c67a..48bcc7d2b33b 100644
@@ -176,11 +176,13 @@ static int rockchip_pcie_phy_power_on(struct phy *phy)
 				   PHY_CFG_ADDR_MASK,
 				   PHY_CFG_ADDR_SHIFT));
 
-	regmap_write(rk_phy->reg_base,
-		     rk_phy->phy_data->pcie_laneoff,
-		     HIWORD_UPDATE(!PHY_LANE_IDLE_OFF,
-				   PHY_LANE_IDLE_MASK,
-				   PHY_LANE_IDLE_A_SHIFT + inst->index));
+	for (int i=0; i < PHY_MAX_LANE_NUM; i++) {
+		regmap_write(rk_phy->reg_base,
+			     rk_phy->phy_data->pcie_laneoff,
+			     HIWORD_UPDATE(!PHY_LANE_IDLE_OFF,
+					   PHY_LANE_IDLE_MASK,
+					   PHY_LANE_IDLE_A_SHIFT + i));
+	}
 
 	/*
 	 * No documented timeout value for phy operation below,
Signature · 1 line
2.49.0
#7 lore raw

RFC PATCH v3 5/5 phy: rockchip-pcie: Adjust read mask and write

In reply to Geraldo Nascimento

Section 17.6.10 of the RK3399 TRM "PCIe PIPE PHY registers Description" defines asynchronous strobe TEST_WRITE which should be enabled then disabled and seems to have been copy-pasted as of current. Adjust it. While at it, adjust read mask which should be the same as write mask.

---
 drivers/phy/rockchip/phy-rockchip-pcie.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
drivers/phy/rockchip/phy-rockchip-pcie.c +2 -2
index 48bcc7d2b33b..35d2523ee776 100644
@@ -30,9 +30,9 @@
 #define PHY_CFG_ADDR_SHIFT    1
 #define PHY_CFG_DATA_MASK     0xf
 #define PHY_CFG_ADDR_MASK     0x3f
-#define PHY_CFG_RD_MASK       0x3ff
+#define PHY_CFG_RD_MASK       0x3f
 #define PHY_CFG_WR_ENABLE     1
-#define PHY_CFG_WR_DISABLE    1
+#define PHY_CFG_WR_DISABLE    0
 #define PHY_CFG_WR_SHIFT      0
 #define PHY_CFG_WR_MASK       1
 #define PHY_CFG_PLL_LOCK      0x10
Signature · 1 line
2.49.0