[PATCH net-next 2/2] amd-xgbe: add support for P100a platform
From: Raju Rangoju
Date: Sun Mar 01 2026 - 23:47:37 EST
Add hardware support for the AMD P100a platform featuring the ethernet
controller PCI device ID 0x1122.
Platform-specific changes include:
1. PCI device ID and register configuration:
- Add XGBE_P100a_PCI_DEVICE_ID (0x1122) for recognition
- Configure platform-specific XPCS window registers
- Disable CDR workaround and RRC for this platform
2. XPCS window offset calculation fix:
The P100a platform uses a different memory mapping scheme for XPCS
register access. The offset calculation differs between platforms:
- Older platforms (YC): offset = base + (addr & mask)
The address is masked first, then added to the window base.
- P100a: offset = (base + addr) & mask
The full address is added to base first, then masked.
This is critical because using the wrong calculation causes register
reads/writes to access incorrect addresses, leading to incorrect
behaviour.
3. 2.5G speed mode handling:
P100a uses XGMII mode (ss=0x06) for 2.5G instead of GMII mode
(ss=0x02) used by older platforms. The MAC version check determines
which mode to use.
4. Port speed bits extended:
Extend XP_PROP_0_PORT_SPEEDS from 5 bits to 6 bits to support the
additional 5G speed capability.
5. Rx adaptation disabled:
Rx adaptation is disabled for P100a (MAC version 0x33) as this
feature requires further development for this platform.
6. Rate change command for 2.5G:
Use XGBE_MB_SUBCMD_2_5G_KX subcommand for 2.5G mode on P100a
instead of XGBE_MB_SUBCMD_NONE used on older platforms.
Signed-off-by: Raju Rangoju <Raju.Rangoju@xxxxxxx>
---
drivers/net/ethernet/amd/xgbe/xgbe-common.h | 4 ++-
drivers/net/ethernet/amd/xgbe/xgbe-dev.c | 33 +++++++++++++++++++--
drivers/net/ethernet/amd/xgbe/xgbe-pci.c | 8 +++++
drivers/net/ethernet/amd/xgbe/xgbe-phy-v2.c | 22 ++++++++++++--
drivers/net/ethernet/amd/xgbe/xgbe.h | 6 +++-
5 files changed, 65 insertions(+), 8 deletions(-)
diff --git a/drivers/net/ethernet/amd/xgbe/xgbe-common.h b/drivers/net/ethernet/amd/xgbe/xgbe-common.h
index 711f295eb777..57cd8d2e1ad7 100644
--- a/drivers/net/ethernet/amd/xgbe/xgbe-common.h
+++ b/drivers/net/ethernet/amd/xgbe/xgbe-common.h
@@ -832,6 +832,8 @@
#define PCS_V2_YC_WINDOW_SELECT 0x18064
#define PCS_V3_RN_WINDOW_DEF 0xf8078
#define PCS_V3_RN_WINDOW_SELECT 0xf807c
+#define PCS_P100a_WINDOW_DEF 0x8060
+#define PCS_P100a_WINDOW_SELECT 0x8080
#define PCS_RN_SMN_BASE_ADDR 0x11e00000
#define PCS_RN_PORT_ADDR_SIZE 0x100000
@@ -968,7 +970,7 @@
#define XP_PROP_0_PORT_MODE_INDEX 8
#define XP_PROP_0_PORT_MODE_WIDTH 4
#define XP_PROP_0_PORT_SPEEDS_INDEX 22
-#define XP_PROP_0_PORT_SPEEDS_WIDTH 5
+#define XP_PROP_0_PORT_SPEEDS_WIDTH 6
#define XP_PROP_1_MAX_RX_DMA_INDEX 24
#define XP_PROP_1_MAX_RX_DMA_WIDTH 5
#define XP_PROP_1_MAX_RX_QUEUES_INDEX 8
diff --git a/drivers/net/ethernet/amd/xgbe/xgbe-dev.c b/drivers/net/ethernet/amd/xgbe/xgbe-dev.c
index 1a91ec455bee..f1357619097e 100644
--- a/drivers/net/ethernet/amd/xgbe/xgbe-dev.c
+++ b/drivers/net/ethernet/amd/xgbe/xgbe-dev.c
@@ -718,7 +718,7 @@ static void xgbe_disable_ecc_sec(struct xgbe_prv_data *pdata,
static int xgbe_set_speed(struct xgbe_prv_data *pdata, int speed)
{
- unsigned int ss;
+ unsigned int ss, ver;
switch (speed) {
case SPEED_10:
@@ -728,7 +728,12 @@ static int xgbe_set_speed(struct xgbe_prv_data *pdata, int speed)
ss = XGBE_MAC_SS_1G;
break;
case SPEED_2500:
- ss = XGBE_MAC_SS_2_5G_GMII;
+ /* P100a uses XGMII mode for 2.5G, older platforms use GMII */
+ ver = XGMAC_GET_BITS(pdata->hw_feat.version, MAC_VR, SNPSVER);
+ if (ver == XGBE_MAC_VER_33)
+ ss = XGBE_MAC_SS_2_5G_XGMII;
+ else
+ ss = XGBE_MAC_SS_2_5G_GMII;
break;
case SPEED_10000:
ss = XGBE_MAC_SS_10G;
@@ -1070,6 +1075,8 @@ static void xgbe_get_pcs_index_and_offset(struct xgbe_prv_data *pdata,
unsigned int *index,
unsigned int *offset)
{
+ unsigned int ver;
+
/* The PCS registers are accessed using mmio. The underlying
* management interface uses indirect addressing to access the MMD
* register sets. This requires accessing of the PCS register in two
@@ -1081,7 +1088,27 @@ static void xgbe_get_pcs_index_and_offset(struct xgbe_prv_data *pdata,
*/
mmd_address <<= 1;
*index = mmd_address & ~pdata->xpcs_window_mask;
- *offset = pdata->xpcs_window + (mmd_address & pdata->xpcs_window_mask);
+
+ ver = XGMAC_GET_BITS(pdata->hw_feat.version, MAC_VR, SNPSVER);
+
+ /* The P100a platform uses a different memory mapping scheme for XPCS
+ * register access. The offset calculation differs between platforms:
+ *
+ * For P100a platforms: The offset is calculated by adding the
+ * mmd_address to the xpcs_window and then applying the xpcs_window_mask
+ * For older platforms: The offset is calculated by applying the
+ * xpcs_window_mask to the mmd_address and then adding it to the
+ * xpcs_window.
+ *
+ * This is critical because using the wrong calculation causes register
+ * accesses to target the wrong registers, leading to incorrect behavior
+ */
+ if (ver == XGBE_MAC_VER_33)
+ *offset = (pdata->xpcs_window + mmd_address) &
+ pdata->xpcs_window_mask;
+ else
+ *offset = pdata->xpcs_window +
+ (mmd_address & pdata->xpcs_window_mask);
}
static int xgbe_read_mmd_regs_v3(struct xgbe_prv_data *pdata, int prtad,
diff --git a/drivers/net/ethernet/amd/xgbe/xgbe-pci.c b/drivers/net/ethernet/amd/xgbe/xgbe-pci.c
index e3e1dca9856a..f54a5040a493 100644
--- a/drivers/net/ethernet/amd/xgbe/xgbe-pci.c
+++ b/drivers/net/ethernet/amd/xgbe/xgbe-pci.c
@@ -168,6 +168,14 @@ static int xgbe_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
rdev = pci_get_domain_bus_and_slot(0, 0, PCI_DEVFN(0, 0));
if (rdev && rdev->vendor == PCI_VENDOR_ID_AMD) {
switch (rdev->device) {
+ case XGBE_P100a_PCI_DEVICE_ID:
+ pdata->xpcs_window_def_reg = PCS_P100a_WINDOW_DEF;
+ pdata->xpcs_window_sel_reg = PCS_P100a_WINDOW_SELECT;
+
+ /* P100a devices do not need rrc and cdr workaround */
+ pdata->vdata->an_cdr_workaround = 0;
+ pdata->vdata->enable_rrc = 0;
+ break;
case XGBE_RV_PCI_DEVICE_ID:
pdata->xpcs_window_def_reg = PCS_V2_RV_WINDOW_DEF;
pdata->xpcs_window_sel_reg = PCS_V2_RV_WINDOW_SELECT;
diff --git a/drivers/net/ethernet/amd/xgbe/xgbe-phy-v2.c b/drivers/net/ethernet/amd/xgbe/xgbe-phy-v2.c
index c63ddb12237e..1dbfa9d4360d 100644
--- a/drivers/net/ethernet/amd/xgbe/xgbe-phy-v2.c
+++ b/drivers/net/ethernet/amd/xgbe/xgbe-phy-v2.c
@@ -2132,7 +2132,11 @@ static bool enable_rx_adap(struct xgbe_prv_data *pdata, enum xgbe_mode mode)
/* Rx-Adaptation is not supported on older platforms(< 0x30H) */
ver = XGMAC_GET_BITS(pdata->hw_feat.version, MAC_VR, SNPSVER);
- if (ver < 0x30)
+ if (ver < XGBE_MAC_VER_30)
+ return false;
+
+ /* Rx adaptation not yet supported on P100a */
+ if (ver == XGBE_MAC_VER_33)
return false;
/* Re-driver models 4223 && 4227 do not support Rx-Adaptation */
@@ -2258,12 +2262,24 @@ static void xgbe_phy_kr_mode(struct xgbe_prv_data *pdata)
static void xgbe_phy_kx_2500_mode(struct xgbe_prv_data *pdata)
{
+ unsigned int ver;
+
struct xgbe_phy_data *phy_data = pdata->phy_data;
xgbe_phy_set_redrv_mode(pdata);
- /* 2.5G/KX */
- xgbe_phy_perform_ratechange(pdata, XGBE_MB_CMD_SET_2_5G, XGBE_MB_SUBCMD_NONE);
+ ver = XGMAC_GET_BITS(pdata->hw_feat.version, MAC_VR, SNPSVER);
+
+ /*
+ * P100a uses XGMII mode for 2.5G which requires the 2.5G_KX subcommand.
+ * Older platforms use GMII mode.
+ */
+ if (ver == XGBE_MAC_VER_33)
+ xgbe_phy_perform_ratechange(pdata, XGBE_MB_CMD_SET_2_5G,
+ XGBE_MB_SUBCMD_2_5G_KX);
+ else
+ xgbe_phy_perform_ratechange(pdata, XGBE_MB_CMD_SET_2_5G,
+ XGBE_MB_SUBCMD_NONE);
phy_data->cur_mode = XGBE_MODE_KX_2500;
diff --git a/drivers/net/ethernet/amd/xgbe/xgbe.h b/drivers/net/ethernet/amd/xgbe/xgbe.h
index 32cab96e013c..f1b2954017e6 100644
--- a/drivers/net/ethernet/amd/xgbe/xgbe.h
+++ b/drivers/net/ethernet/amd/xgbe/xgbe.h
@@ -262,6 +262,7 @@
#define XGBE_RV_PCI_DEVICE_ID 0x15d0
#define XGBE_YC_PCI_DEVICE_ID 0x14b5
#define XGBE_RN_PCI_DEVICE_ID 0x1630
+#define XGBE_P100a_PCI_DEVICE_ID 0x1122
/* Generic low and high masks */
#define XGBE_GEN_HI_MASK GENMASK(31, 16)
@@ -577,7 +578,10 @@ enum xgbe_mb_subcmd {
XGBE_MB_SUBCMD_10MBITS = 0,
XGBE_MB_SUBCMD_100MBITS,
XGBE_MB_SUBCMD_1G_SGMII,
- XGBE_MB_SUBCMD_1G_KX
+ XGBE_MB_SUBCMD_1G_KX,
+
+ /* 2.5GbE Mode subcommands */
+ XGBE_MB_SUBCMD_2_5G_KX = 1
};
struct xgbe_phy {
--
2.34.1