From ed6c24eda97b6bdcd013dbd91cc5c8b02de507e9 Mon Sep 17 00:00:00 2001 From: Jon Mason Date: Mon, 15 Jul 2013 16:43:54 -0700 Subject: NTB: NTB-RP support Add support for Non-Transparent Bridge connected to a PCI-E Root Port on the remote system (also known as NTB-RP mode). This allows for a NTB enabled system to be connected to a non-NTB enabled system/slot. Modifications to the registers and BARs/MWs on the Secondary side by the remote system are reflected into registers on the Primary side for the local system. Similarly, modifications of registers and BARs/MWs on Primary side by the local system are reflected into registers on the Secondary side for the Remote System. This allows communication between the 2 sides via these registers and BARs/MWs. Note: there is not a fix for the Xeon Errata (that was already worked around in NTB-B2B mode) for NTB-RP mode. Due to this limitation, NTB-RP will not work on the Secondary side with the Xeon Errata workaround enabled. To get around this, disable the workaround via the xeon_errata_workaround=0 modparm. However, this can cause the hang described in the errata. Signed-off-by: Jon Mason --- drivers/ntb/ntb_hw.c | 262 ++++++++++++++++++++++++++++++------------------- drivers/ntb/ntb_regs.h | 5 +- 2 files changed, 163 insertions(+), 104 deletions(-) (limited to 'drivers/ntb') diff --git a/drivers/ntb/ntb_hw.c b/drivers/ntb/ntb_hw.c index 97b18ee..2f3ff73 100644 --- a/drivers/ntb/ntb_hw.c +++ b/drivers/ntb/ntb_hw.c @@ -69,7 +69,7 @@ module_param(xeon_errata_workaround, bool, 0644); MODULE_PARM_DESC(xeon_errata_workaround, "Workaround for the Xeon Errata"); enum { - NTB_CONN_CLASSIC = 0, + NTB_CONN_TRANSPARENT = 0, NTB_CONN_B2B, NTB_CONN_RP, }; @@ -509,7 +509,8 @@ static void ntb_link_event(struct ntb_device *ndev, int link_state) ndev->link_status = NTB_LINK_UP; event = NTB_EVENT_HW_LINK_UP; - if (ndev->hw_type == BWD_HW) + if (ndev->hw_type == BWD_HW || + ndev->conn_type == NTB_CONN_TRANSPARENT) status = readw(ndev->reg_ofs.lnk_stat); else { int rc = pci_read_config_word(ndev->pdev, @@ -649,119 +650,174 @@ static int ntb_xeon_setup(struct ntb_device *ndev) if (rc) return rc; - switch (val & SNB_PPD_CONN_TYPE) { - case NTB_CONN_B2B: - ndev->conn_type = NTB_CONN_B2B; - break; - case NTB_CONN_CLASSIC: - case NTB_CONN_RP: - default: - dev_err(&ndev->pdev->dev, "Only B2B supported at this time\n"); - return -EINVAL; - } - if (val & SNB_PPD_DEV_TYPE) ndev->dev_type = NTB_DEV_USD; else ndev->dev_type = NTB_DEV_DSD; - ndev->reg_ofs.ldb = ndev->reg_base + SNB_PDOORBELL_OFFSET; - ndev->reg_ofs.ldb_mask = ndev->reg_base + SNB_PDBMSK_OFFSET; - ndev->reg_ofs.bar2_xlat = ndev->reg_base + SNB_SBAR2XLAT_OFFSET; - ndev->reg_ofs.bar4_xlat = ndev->reg_base + SNB_SBAR4XLAT_OFFSET; - ndev->reg_ofs.lnk_cntl = ndev->reg_base + SNB_NTBCNTL_OFFSET; - ndev->reg_ofs.lnk_stat = ndev->reg_base + SNB_LINK_STATUS_OFFSET; - ndev->reg_ofs.spad_read = ndev->reg_base + SNB_SPAD_OFFSET; - ndev->reg_ofs.spci_cmd = ndev->reg_base + SNB_PCICMD_OFFSET; - - /* There is a Xeon hardware errata related to writes to - * SDOORBELL or B2BDOORBELL in conjunction with inbound access - * to NTB MMIO Space, which may hang the system. To workaround - * this use the second memory window to access the interrupt and - * scratch pad registers on the remote system. - */ - if (xeon_errata_workaround) { - if (!ndev->mw[1].bar_sz) - return -EINVAL; - - ndev->limits.max_mw = SNB_ERRATA_MAX_MW; - ndev->reg_ofs.spad_write = ndev->mw[1].vbase + - SNB_SPAD_OFFSET; - ndev->reg_ofs.rdb = ndev->mw[1].vbase + - SNB_PDOORBELL_OFFSET; - - /* Set the Limit register to 4k, the minimum size, to - * prevent an illegal access + switch (val & SNB_PPD_CONN_TYPE) { + case NTB_CONN_B2B: + dev_info(&ndev->pdev->dev, "Conn Type = B2B\n"); + ndev->conn_type = NTB_CONN_B2B; + ndev->reg_ofs.ldb = ndev->reg_base + SNB_PDOORBELL_OFFSET; + ndev->reg_ofs.ldb_mask = ndev->reg_base + SNB_PDBMSK_OFFSET; + ndev->reg_ofs.spad_read = ndev->reg_base + SNB_SPAD_OFFSET; + ndev->reg_ofs.bar2_xlat = ndev->reg_base + SNB_SBAR2XLAT_OFFSET; + ndev->reg_ofs.bar4_xlat = ndev->reg_base + SNB_SBAR4XLAT_OFFSET; + ndev->limits.max_spads = SNB_MAX_B2B_SPADS; + + /* There is a Xeon hardware errata related to writes to + * SDOORBELL or B2BDOORBELL in conjunction with inbound access + * to NTB MMIO Space, which may hang the system. To workaround + * this use the second memory window to access the interrupt and + * scratch pad registers on the remote system. */ - writeq(ndev->mw[1].bar_sz + 0x1000, ndev->reg_base + - SNB_PBAR4LMT_OFFSET); - } else { - ndev->limits.max_mw = SNB_MAX_MW; - ndev->reg_ofs.spad_write = ndev->reg_base + - SNB_B2B_SPAD_OFFSET; - ndev->reg_ofs.rdb = ndev->reg_base + - SNB_B2B_DOORBELL_OFFSET; + if (xeon_errata_workaround) { + if (!ndev->mw[1].bar_sz) + return -EINVAL; + + ndev->limits.max_mw = SNB_ERRATA_MAX_MW; + ndev->reg_ofs.spad_write = ndev->mw[1].vbase + + SNB_SPAD_OFFSET; + ndev->reg_ofs.rdb = ndev->mw[1].vbase + + SNB_PDOORBELL_OFFSET; + + /* Set the Limit register to 4k, the minimum size, to + * prevent an illegal access + */ + writeq(ndev->mw[1].bar_sz + 0x1000, ndev->reg_base + + SNB_PBAR4LMT_OFFSET); + } else { + ndev->limits.max_mw = SNB_MAX_MW; + ndev->reg_ofs.spad_write = ndev->reg_base + + SNB_B2B_SPAD_OFFSET; + ndev->reg_ofs.rdb = ndev->reg_base + + SNB_B2B_DOORBELL_OFFSET; + + /* Disable the Limit register, just incase it is set to + * something silly + */ + writeq(0, ndev->reg_base + SNB_PBAR4LMT_OFFSET); + } - /* Disable the Limit register, just incase it is set to - * something silly + /* The Xeon errata workaround requires setting SBAR Base + * addresses to known values, so that the PBAR XLAT can be + * pointed at SBAR0 of the remote system. */ - writeq(0, ndev->reg_base + SNB_PBAR4LMT_OFFSET); - } + if (ndev->dev_type == NTB_DEV_USD) { + writeq(SNB_MBAR23_DSD_ADDR, ndev->reg_base + + SNB_PBAR2XLAT_OFFSET); + if (xeon_errata_workaround) + writeq(SNB_MBAR01_DSD_ADDR, ndev->reg_base + + SNB_PBAR4XLAT_OFFSET); + else { + writeq(SNB_MBAR45_DSD_ADDR, ndev->reg_base + + SNB_PBAR4XLAT_OFFSET); + /* B2B_XLAT_OFFSET is a 64bit register, but can + * only take 32bit writes + */ + writel(SNB_MBAR01_DSD_ADDR & 0xffffffff, + ndev->reg_base + SNB_B2B_XLAT_OFFSETL); + writel(SNB_MBAR01_DSD_ADDR >> 32, + ndev->reg_base + SNB_B2B_XLAT_OFFSETU); + } - /* The Xeon errata workaround requires setting SBAR Base - * addresses to known values, so that the PBAR XLAT can be - * pointed at SBAR0 of the remote system. - */ - if (ndev->dev_type == NTB_DEV_USD) { - writeq(SNB_MBAR23_DSD_ADDR, ndev->reg_base + - SNB_PBAR2XLAT_OFFSET); - if (xeon_errata_workaround) + writeq(SNB_MBAR01_USD_ADDR, ndev->reg_base + + SNB_SBAR0BASE_OFFSET); + writeq(SNB_MBAR23_USD_ADDR, ndev->reg_base + + SNB_SBAR2BASE_OFFSET); + writeq(SNB_MBAR45_USD_ADDR, ndev->reg_base + + SNB_SBAR4BASE_OFFSET); + } else { + writeq(SNB_MBAR23_USD_ADDR, ndev->reg_base + + SNB_PBAR2XLAT_OFFSET); + if (xeon_errata_workaround) + writeq(SNB_MBAR01_USD_ADDR, ndev->reg_base + + SNB_PBAR4XLAT_OFFSET); + else { + writeq(SNB_MBAR45_USD_ADDR, ndev->reg_base + + SNB_PBAR4XLAT_OFFSET); + /* B2B_XLAT_OFFSET is a 64bit register, but can + * only take 32bit writes + */ + writel(SNB_MBAR01_DSD_ADDR & 0xffffffff, + ndev->reg_base + SNB_B2B_XLAT_OFFSETL); + writel(SNB_MBAR01_USD_ADDR >> 32, + ndev->reg_base + SNB_B2B_XLAT_OFFSETU); + } writeq(SNB_MBAR01_DSD_ADDR, ndev->reg_base + - SNB_PBAR4XLAT_OFFSET); - else { + SNB_SBAR0BASE_OFFSET); + writeq(SNB_MBAR23_DSD_ADDR, ndev->reg_base + + SNB_SBAR2BASE_OFFSET); writeq(SNB_MBAR45_DSD_ADDR, ndev->reg_base + - SNB_PBAR4XLAT_OFFSET); - /* B2B_XLAT_OFFSET is a 64bit register, but can - * only take 32bit writes - */ - writel(SNB_MBAR01_USD_ADDR & 0xffffffff, - ndev->reg_base + SNB_B2B_XLAT_OFFSETL); - writel(SNB_MBAR01_DSD_ADDR >> 32, - ndev->reg_base + SNB_B2B_XLAT_OFFSETU); + SNB_SBAR4BASE_OFFSET); } + break; + case NTB_CONN_RP: + dev_info(&ndev->pdev->dev, "Conn Type = RP\n"); + ndev->conn_type = NTB_CONN_RP; - writeq(SNB_MBAR01_USD_ADDR, ndev->reg_base + - SNB_SBAR0BASE_OFFSET); - writeq(SNB_MBAR23_USD_ADDR, ndev->reg_base + - SNB_SBAR2BASE_OFFSET); - writeq(SNB_MBAR45_USD_ADDR, ndev->reg_base + - SNB_SBAR4BASE_OFFSET); - } else { - writeq(SNB_MBAR23_USD_ADDR, ndev->reg_base + - SNB_PBAR2XLAT_OFFSET); - if (xeon_errata_workaround) - writeq(SNB_MBAR01_USD_ADDR, ndev->reg_base + - SNB_PBAR4XLAT_OFFSET); - else { - writeq(SNB_MBAR45_USD_ADDR, ndev->reg_base + - SNB_PBAR4XLAT_OFFSET); - /* B2B_XLAT_OFFSET is a 64bit register, but can - * only take 32bit writes - */ - writel(SNB_MBAR01_USD_ADDR & 0xffffffff, - ndev->reg_base + SNB_B2B_XLAT_OFFSETL); - writel(SNB_MBAR01_USD_ADDR >> 32, - ndev->reg_base + SNB_B2B_XLAT_OFFSETU); + if (xeon_errata_workaround) { + dev_err(&ndev->pdev->dev, + "NTB-RP disabled due to hardware errata. To disregard this warning and potentially lock-up the system, add the parameter 'xeon_errata_workaround=0'.\n"); + return -EINVAL; } - writeq(SNB_MBAR01_DSD_ADDR, ndev->reg_base + - SNB_SBAR0BASE_OFFSET); - writeq(SNB_MBAR23_DSD_ADDR, ndev->reg_base + - SNB_SBAR2BASE_OFFSET); - writeq(SNB_MBAR45_DSD_ADDR, ndev->reg_base + - SNB_SBAR4BASE_OFFSET); + + /* Scratch pads need to have exclusive access from the primary + * or secondary side. Halve the num spads so that each side can + * have an equal amount. + */ + ndev->limits.max_spads = SNB_MAX_COMPAT_SPADS / 2; + /* Note: The SDOORBELL is the cause of the errata. You REALLY + * don't want to touch it. + */ + ndev->reg_ofs.rdb = ndev->reg_base + SNB_SDOORBELL_OFFSET; + ndev->reg_ofs.ldb = ndev->reg_base + SNB_PDOORBELL_OFFSET; + ndev->reg_ofs.ldb_mask = ndev->reg_base + SNB_PDBMSK_OFFSET; + /* Offset the start of the spads to correspond to whether it is + * primary or secondary + */ + ndev->reg_ofs.spad_write = ndev->reg_base + SNB_SPAD_OFFSET + + ndev->limits.max_spads * 4; + ndev->reg_ofs.spad_read = ndev->reg_base + SNB_SPAD_OFFSET; + ndev->reg_ofs.bar2_xlat = ndev->reg_base + SNB_SBAR2XLAT_OFFSET; + ndev->reg_ofs.bar4_xlat = ndev->reg_base + SNB_SBAR4XLAT_OFFSET; + ndev->limits.max_mw = SNB_MAX_MW; + break; + case NTB_CONN_TRANSPARENT: + dev_info(&ndev->pdev->dev, "Conn Type = TRANSPARENT\n"); + ndev->conn_type = NTB_CONN_TRANSPARENT; + /* Scratch pads need to have exclusive access from the primary + * or secondary side. Halve the num spads so that each side can + * have an equal amount. + */ + ndev->limits.max_spads = SNB_MAX_COMPAT_SPADS / 2; + ndev->reg_ofs.rdb = ndev->reg_base + SNB_PDOORBELL_OFFSET; + ndev->reg_ofs.ldb = ndev->reg_base + SNB_SDOORBELL_OFFSET; + ndev->reg_ofs.ldb_mask = ndev->reg_base + SNB_SDBMSK_OFFSET; + ndev->reg_ofs.spad_write = ndev->reg_base + SNB_SPAD_OFFSET; + /* Offset the start of the spads to correspond to whether it is + * primary or secondary + */ + ndev->reg_ofs.spad_read = ndev->reg_base + SNB_SPAD_OFFSET + + ndev->limits.max_spads * 4; + ndev->reg_ofs.bar2_xlat = ndev->reg_base + SNB_PBAR2XLAT_OFFSET; + ndev->reg_ofs.bar4_xlat = ndev->reg_base + SNB_PBAR4XLAT_OFFSET; + + ndev->limits.max_mw = SNB_MAX_MW; + break; + default: + /* Most likely caused by the remote NTB-RP device not being + * configured + */ + dev_err(&ndev->pdev->dev, "Unknown PPD %x\n", val); + return -EINVAL; } - ndev->limits.max_spads = SNB_MAX_B2B_SPADS; + ndev->reg_ofs.lnk_cntl = ndev->reg_base + SNB_NTBCNTL_OFFSET; + ndev->reg_ofs.lnk_stat = ndev->reg_base + SNB_SLINK_STATUS_OFFSET; + ndev->reg_ofs.spci_cmd = ndev->reg_base + SNB_PCICMD_OFFSET; + ndev->limits.max_db_bits = SNB_MAX_DB_BITS; ndev->limits.msix_cnt = SNB_MSIX_CNT; ndev->bits_per_vector = SNB_DB_BITS_PER_VEC; @@ -865,8 +921,10 @@ static int ntb_device_setup(struct ntb_device *ndev) dev_info(&ndev->pdev->dev, "Device Type = %s\n", ndev->dev_type == NTB_DEV_USD ? "USD/DSP" : "DSD/USP"); - /* Enable Bus Master and Memory Space on the secondary side */ - writew(PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER, ndev->reg_ofs.spci_cmd); + if (ndev->conn_type == NTB_CONN_B2B) + /* Enable Bus Master and Memory Space on the secondary side */ + writew(PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER, + ndev->reg_ofs.spci_cmd); return 0; } @@ -1360,7 +1418,7 @@ static void ntb_pci_remove(struct pci_dev *pdev) /* Bring NTB link down */ ntb_cntl = readl(ndev->reg_ofs.lnk_cntl); - ntb_cntl |= NTB_LINK_DISABLE; + ntb_cntl |= NTB_CNTL_LINK_DISABLE; writel(ntb_cntl, ndev->reg_ofs.lnk_cntl); ntb_transport_free(ndev->ntb_transport); diff --git a/drivers/ntb/ntb_regs.h b/drivers/ntb/ntb_regs.h index 03a66ef..b4f4604 100644 --- a/drivers/ntb/ntb_regs.h +++ b/drivers/ntb/ntb_regs.h @@ -46,8 +46,6 @@ * Jon Mason */ -#define NTB_LINK_ENABLE 0x0000 -#define NTB_LINK_DISABLE 0x0002 #define NTB_LINK_STATUS_ACTIVE 0x2000 #define NTB_LINK_SPEED_MASK 0x000f #define NTB_LINK_WIDTH_MASK 0x03f0 @@ -65,6 +63,7 @@ #define SNB_PCICMD_OFFSET 0x0504 #define SNB_DEVCTRL_OFFSET 0x0598 +#define SNB_SLINK_STATUS_OFFSET 0x05A2 #define SNB_LINK_STATUS_OFFSET 0x01A2 #define SNB_PBAR2LMT_OFFSET 0x0000 @@ -147,6 +146,8 @@ #define BWD_LTSSMSTATEJMP_FORCEDETECT (1 << 2) #define BWD_IBIST_ERR_OFLOW 0x7FFF7FFF +#define NTB_CNTL_CFG_LOCK (1 << 0) +#define NTB_CNTL_LINK_DISABLE (1 << 1) #define NTB_CNTL_BAR23_SNOOP (1 << 2) #define NTB_CNTL_BAR45_SNOOP (1 << 6) #define BWD_CNTL_LINK_DOWN (1 << 16) -- cgit v1.1