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ntb: Adding split BAR support for Haswell platforms

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On the Haswell platform, a split BAR option to allow creation of 2
32bit BARs (4 and 5) from the 64bit BAR 4. Adding support for this
new option.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
This commit is contained in:
Dave Jiang 2014-08-28 13:53:23 -07:00 committed by Jon Mason
parent 069684e888
commit ab760a0c56
3 changed files with 210 additions and 60 deletions
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225
drivers/ntb/ntb_hw.c
View file

@ -84,8 +84,8 @@ static struct dentry *debugfs_dir;
#define BWD_LINK_RECOVERY_TIME 500
/* Translate memory window 0,1 to BAR 2,4 */
#define MW_TO_BAR(mw) (mw * NTB_MAX_NUM_MW + 2)
/* Translate memory window 0,1,2 to BAR 2,4,5 */
#define MW_TO_BAR(mw) (mw == 0 ? 2 : (mw == 1 ? 4 : 5))
static const struct pci_device_id ntb_pci_tbl[] = {
{PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_B2B_BWD)},
@ -506,8 +506,14 @@ void ntb_set_mw_addr(struct ntb_device *ndev, unsigned int mw, u64 addr)
case NTB_BAR_23:
writeq(addr, ndev->reg_ofs.bar2_xlat);
break;
case NTB_BAR_45:
writeq(addr, ndev->reg_ofs.bar4_xlat);
case NTB_BAR_4:
if (ndev->split_bar)
writel(addr, ndev->reg_ofs.bar4_xlat);
else
writeq(addr, ndev->reg_ofs.bar4_xlat);
break;
case NTB_BAR_5:
writel(addr, ndev->reg_ofs.bar5_xlat);
break;
}
}
@ -729,6 +735,9 @@ static int ntb_xeon_setup(struct ntb_device *ndev)
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;
if (ndev->split_bar)
ndev->reg_ofs.bar5_xlat =
ndev->reg_base + SNB_SBAR5XLAT_OFFSET;
ndev->limits.max_spads = SNB_MAX_B2B_SPADS;
/* There is a Xeon hardware errata related to writes to
@ -738,15 +747,16 @@ static int ntb_xeon_setup(struct ntb_device *ndev)
* scratch pad registers on the remote system.
*/
if (ndev->wa_flags & WA_SNB_ERR) {
if (!ndev->mw[1].bar_sz)
if (!ndev->mw[ndev->limits.max_mw - 1].bar_sz)
return -EINVAL;
ndev->limits.max_mw = SNB_ERRATA_MAX_MW;
ndev->limits.max_db_bits = SNB_MAX_DB_BITS;
ndev->reg_ofs.spad_write = ndev->mw[1].vbase +
SNB_SPAD_OFFSET;
ndev->reg_ofs.rdb = ndev->mw[1].vbase +
SNB_PDOORBELL_OFFSET;
ndev->reg_ofs.spad_write =
ndev->mw[ndev->limits.max_mw - 1].vbase +
SNB_SPAD_OFFSET;
ndev->reg_ofs.rdb =
ndev->mw[ndev->limits.max_mw - 1].vbase +
SNB_PDOORBELL_OFFSET;
/* Set the Limit register to 4k, the minimum size, to
* prevent an illegal access
@ -759,9 +769,9 @@ static int ntb_xeon_setup(struct ntb_device *ndev)
* the driver defaults, but write the Limit registers
* first just in case.
*/
} else {
ndev->limits.max_mw = SNB_MAX_MW;
ndev->limits.max_mw = SNB_ERRATA_MAX_MW;
} else {
/* HW Errata on bit 14 of b2bdoorbell register. Writes
* will not be mirrored to the remote system. Shrink
* the number of bits by one, since bit 14 is the last
@ -774,7 +784,8 @@ static int ntb_xeon_setup(struct ntb_device *ndev)
SNB_B2B_DOORBELL_OFFSET;
/* Disable the Limit register, just incase it is set to
* something silly
* something silly. A 64bit write should handle it
* regardless of whether it has a split BAR or not.
*/
writeq(0, ndev->reg_base + SNB_PBAR4LMT_OFFSET);
/* HW errata on the Limit registers. They can only be
@ -783,6 +794,10 @@ static int ntb_xeon_setup(struct ntb_device *ndev)
* the driver defaults, but write the Limit registers
* first just in case.
*/
if (ndev->split_bar)
ndev->limits.max_mw = HSX_SPLITBAR_MAX_MW;
else
ndev->limits.max_mw = SNB_MAX_MW;
}
/* The Xeon errata workaround requires setting SBAR Base
@ -796,8 +811,18 @@ static int ntb_xeon_setup(struct ntb_device *ndev)
writeq(SNB_MBAR01_DSD_ADDR, ndev->reg_base +
SNB_PBAR4XLAT_OFFSET);
else {
writeq(SNB_MBAR45_DSD_ADDR, ndev->reg_base +
SNB_PBAR4XLAT_OFFSET);
if (ndev->split_bar) {
writel(SNB_MBAR4_DSD_ADDR,
ndev->reg_base +
SNB_PBAR4XLAT_OFFSET);
writel(SNB_MBAR5_DSD_ADDR,
ndev->reg_base +
SNB_PBAR5XLAT_OFFSET);
} else
writeq(SNB_MBAR4_DSD_ADDR,
ndev->reg_base +
SNB_PBAR4XLAT_OFFSET);
/* B2B_XLAT_OFFSET is a 64bit register, but can
* only take 32bit writes
*/
@ -811,8 +836,14 @@ static int ntb_xeon_setup(struct ntb_device *ndev)
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);
if (ndev->split_bar) {
writel(SNB_MBAR4_USD_ADDR, ndev->reg_base +
SNB_SBAR4BASE_OFFSET);
writel(SNB_MBAR5_USD_ADDR, ndev->reg_base +
SNB_SBAR5BASE_OFFSET);
} else
writeq(SNB_MBAR4_USD_ADDR, ndev->reg_base +
SNB_SBAR4BASE_OFFSET);
} else {
writeq(SNB_MBAR23_USD_ADDR, ndev->reg_base +
SNB_PBAR2XLAT_OFFSET);
@ -820,9 +851,20 @@ static int ntb_xeon_setup(struct ntb_device *ndev)
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
if (ndev->split_bar) {
writel(SNB_MBAR4_USD_ADDR,
ndev->reg_base +
SNB_PBAR4XLAT_OFFSET);
writel(SNB_MBAR5_USD_ADDR,
ndev->reg_base +
SNB_PBAR5XLAT_OFFSET);
} else
writeq(SNB_MBAR4_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,
@ -834,8 +876,15 @@ static int ntb_xeon_setup(struct ntb_device *ndev)
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);
if (ndev->split_bar) {
writel(SNB_MBAR4_DSD_ADDR, ndev->reg_base +
SNB_SBAR4BASE_OFFSET);
writel(SNB_MBAR5_DSD_ADDR, ndev->reg_base +
SNB_SBAR5BASE_OFFSET);
} else
writeq(SNB_MBAR4_DSD_ADDR, ndev->reg_base +
SNB_SBAR4BASE_OFFSET);
}
break;
case NTB_CONN_RP:
@ -865,7 +914,12 @@ static int ntb_xeon_setup(struct ntb_device *ndev)
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;
if (ndev->split_bar) {
ndev->reg_ofs.bar5_xlat =
ndev->reg_base + SNB_SBAR5XLAT_OFFSET;
ndev->limits.max_mw = HSX_SPLITBAR_MAX_MW;
} else
ndev->limits.max_mw = SNB_MAX_MW;
break;
case NTB_CONN_TRANSPARENT:
if (ndev->wa_flags & WA_SNB_ERR) {
@ -892,7 +946,12 @@ static int ntb_xeon_setup(struct ntb_device *ndev)
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;
if (ndev->split_bar) {
ndev->reg_ofs.bar5_xlat =
ndev->reg_base + SNB_PBAR5XLAT_OFFSET;
ndev->limits.max_mw = HSX_SPLITBAR_MAX_MW;
} else
ndev->limits.max_mw = SNB_MAX_MW;
break;
default:
/*
@ -1499,7 +1558,11 @@ static void ntb_hw_link_up(struct ntb_device *ndev)
ntb_cntl = readl(ndev->reg_ofs.lnk_cntl);
ntb_cntl &= ~(NTB_CNTL_LINK_DISABLE | NTB_CNTL_CFG_LOCK);
ntb_cntl |= NTB_CNTL_P2S_BAR23_SNOOP | NTB_CNTL_S2P_BAR23_SNOOP;
ntb_cntl |= NTB_CNTL_P2S_BAR45_SNOOP | NTB_CNTL_S2P_BAR45_SNOOP;
ntb_cntl |= NTB_CNTL_P2S_BAR4_SNOOP | NTB_CNTL_S2P_BAR4_SNOOP;
if (ndev->split_bar)
ntb_cntl |= NTB_CNTL_P2S_BAR5_SNOOP |
NTB_CNTL_S2P_BAR5_SNOOP;
writel(ntb_cntl, ndev->reg_ofs.lnk_cntl);
}
}
@ -1516,14 +1579,26 @@ static void ntb_hw_link_down(struct ntb_device *ndev)
/* Bring NTB link down */
ntb_cntl = readl(ndev->reg_ofs.lnk_cntl);
ntb_cntl &= ~(NTB_CNTL_P2S_BAR23_SNOOP | NTB_CNTL_S2P_BAR23_SNOOP);
ntb_cntl &= ~(NTB_CNTL_P2S_BAR45_SNOOP | NTB_CNTL_S2P_BAR45_SNOOP);
ntb_cntl &= ~(NTB_CNTL_P2S_BAR4_SNOOP | NTB_CNTL_S2P_BAR4_SNOOP);
if (ndev->split_bar)
ntb_cntl &= ~(NTB_CNTL_P2S_BAR5_SNOOP |
NTB_CNTL_S2P_BAR5_SNOOP);
ntb_cntl |= NTB_CNTL_LINK_DISABLE | NTB_CNTL_CFG_LOCK;
writel(ntb_cntl, ndev->reg_ofs.lnk_cntl);
}
static void ntb_max_mw_detect(struct ntb_device *ndev)
{
if (ndev->split_bar)
ndev->limits.max_mw = HSX_SPLITBAR_MAX_MW;
else
ndev->limits.max_mw = SNB_MAX_MW;
}
static int ntb_xeon_detect(struct ntb_device *ndev)
{
int rc;
int rc, bars_mask;
u32 bars;
u8 ppd;
ndev->hw_type = SNB_HW;
@ -1537,6 +1612,8 @@ static int ntb_xeon_detect(struct ntb_device *ndev)
else
ndev->dev_type = NTB_DEV_DSD;
ndev->split_bar = (ppd & SNB_PPD_SPLIT_BAR) ? 1 : 0;
switch (ppd & SNB_PPD_CONN_TYPE) {
case NTB_CONN_B2B:
dev_info(&ndev->pdev->dev, "Conn Type = B2B\n");
@ -1555,12 +1632,25 @@ static int ntb_xeon_detect(struct ntb_device *ndev)
* NTB. We will just force correct here.
*/
ndev->dev_type = NTB_DEV_USD;
/*
* This is a way for transparent BAR to figure out if we
* are doing split BAR or not. There is no way for the hw
* on the transparent side to know and set the PPD.
*/
bars_mask = pci_select_bars(ndev->pdev, IORESOURCE_MEM);
bars = hweight32(bars_mask);
if (bars == (HSX_SPLITBAR_MAX_MW + 1))
ndev->split_bar = 1;
break;
default:
dev_err(&ndev->pdev->dev, "Unknown PPD %x\n", ppd);
return -ENODEV;
}
ntb_max_mw_detect(ndev);
return 0;
}
@ -1638,22 +1728,50 @@ static int ntb_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
if (rc)
goto err;
rc = pci_request_selected_regions(pdev, NTB_BAR_MASK, KBUILD_MODNAME);
if (rc)
ndev->mw = kcalloc(ndev->limits.max_mw, sizeof(struct ntb_mw),
GFP_KERNEL);
if (!ndev->mw) {
rc = -ENOMEM;
goto err1;
}
if (ndev->split_bar)
rc = pci_request_selected_regions(pdev, NTB_SPLITBAR_MASK,
KBUILD_MODNAME);
else
rc = pci_request_selected_regions(pdev, NTB_BAR_MASK,
KBUILD_MODNAME);
if (rc)
goto err2;
ndev->reg_base = pci_ioremap_bar(pdev, NTB_BAR_MMIO);
if (!ndev->reg_base) {
dev_warn(&pdev->dev, "Cannot remap BAR 0\n");
rc = -EIO;
goto err2;
goto err3;
}
for (i = 0; i < NTB_MAX_NUM_MW; i++) {
for (i = 0; i < ndev->limits.max_mw; i++) {
ndev->mw[i].bar_sz = pci_resource_len(pdev, MW_TO_BAR(i));
ndev->mw[i].vbase =
ioremap_wc(pci_resource_start(pdev, MW_TO_BAR(i)),
ndev->mw[i].bar_sz);
/*
* with the errata we need to steal last of the memory
* windows for workarounds and they point to MMIO registers.
*/
if ((ndev->wa_flags & WA_SNB_ERR) &&
(i == (ndev->limits.max_mw - 1))) {
ndev->mw[i].vbase =
ioremap_nocache(pci_resource_start(pdev,
MW_TO_BAR(i)),
ndev->mw[i].bar_sz);
} else {
ndev->mw[i].vbase =
ioremap_wc(pci_resource_start(pdev,
MW_TO_BAR(i)),
ndev->mw[i].bar_sz);
}
dev_info(&pdev->dev, "MW %d size %llu\n", i,
(unsigned long long) ndev->mw[i].bar_sz);
if (!ndev->mw[i].vbase) {
@ -1668,7 +1786,7 @@ static int ntb_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
if (rc) {
rc = pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
if (rc)
goto err3;
goto err4;
dev_warn(&pdev->dev, "Cannot DMA highmem\n");
}
@ -1677,22 +1795,22 @@ static int ntb_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
if (rc) {
rc = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(32));
if (rc)
goto err3;
goto err4;
dev_warn(&pdev->dev, "Cannot DMA consistent highmem\n");
}
rc = ntb_device_setup(ndev);
if (rc)
goto err3;
goto err4;
rc = ntb_create_callbacks(ndev);
if (rc)
goto err4;
goto err5;
rc = ntb_setup_interrupts(ndev);
if (rc)
goto err5;
goto err6;
/* The scratchpad registers keep the values between rmmod/insmod,
* blast them now
@ -1704,24 +1822,29 @@ static int ntb_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
rc = ntb_transport_init(pdev);
if (rc)
goto err6;
goto err7;
ntb_hw_link_up(ndev);
return 0;
err6:
err7:
ntb_free_interrupts(ndev);
err5:
err6:
ntb_free_callbacks(ndev);
err4:
err5:
ntb_device_free(ndev);
err3:
err4:
for (i--; i >= 0; i--)
iounmap(ndev->mw[i].vbase);
iounmap(ndev->reg_base);
err3:
if (ndev->split_bar)
pci_release_selected_regions(pdev, NTB_SPLITBAR_MASK);
else
pci_release_selected_regions(pdev, NTB_BAR_MASK);
err2:
pci_release_selected_regions(pdev, NTB_BAR_MASK);
kfree(ndev->mw);
err1:
pci_disable_device(pdev);
err:
@ -1745,11 +1868,19 @@ static void ntb_pci_remove(struct pci_dev *pdev)
ntb_free_callbacks(ndev);
ntb_device_free(ndev);
for (i = 0; i < NTB_MAX_NUM_MW; i++)
/* need to reset max_mw limits so we can unmap properly */
if (ndev->hw_type == SNB_HW)
ntb_max_mw_detect(ndev);
for (i = 0; i < ndev->limits.max_mw; i++)
iounmap(ndev->mw[i].vbase);
kfree(ndev->mw);
iounmap(ndev->reg_base);
pci_release_selected_regions(pdev, NTB_BAR_MASK);
if (ndev->split_bar)
pci_release_selected_regions(pdev, NTB_SPLITBAR_MASK);
else
pci_release_selected_regions(pdev, NTB_BAR_MASK);
pci_disable_device(pdev);
ntb_free_debugfs(ndev);
kfree(ndev);

14
drivers/ntb/ntb_hw.h
View file

@ -78,14 +78,16 @@ static inline void writeq(u64 val, void __iomem *addr)
#define NTB_BAR_MMIO 0
#define NTB_BAR_23 2
#define NTB_BAR_45 4
#define NTB_BAR_4 4
#define NTB_BAR_5 5
#define NTB_BAR_MASK ((1 << NTB_BAR_MMIO) | (1 << NTB_BAR_23) |\
(1 << NTB_BAR_45))
(1 << NTB_BAR_4))
#define NTB_SPLITBAR_MASK ((1 << NTB_BAR_MMIO) | (1 << NTB_BAR_23) |\
(1 << NTB_BAR_4) | (1 << NTB_BAR_5))
#define NTB_HB_TIMEOUT msecs_to_jiffies(1000)
#define NTB_MAX_NUM_MW 2
enum ntb_hw_event {
NTB_EVENT_SW_EVENT0 = 0,
NTB_EVENT_SW_EVENT1,
@ -115,7 +117,7 @@ struct ntb_device {
struct pci_dev *pdev;
struct msix_entry *msix_entries;
void __iomem *reg_base;
struct ntb_mw mw[NTB_MAX_NUM_MW];
struct ntb_mw *mw;
struct {
unsigned char max_mw;
unsigned char max_spads;
@ -128,6 +130,7 @@ struct ntb_device {
void __iomem *rdb;
void __iomem *bar2_xlat;
void __iomem *bar4_xlat;
void __iomem *bar5_xlat;
void __iomem *spad_write;
void __iomem *spad_read;
void __iomem *lnk_cntl;
@ -147,6 +150,7 @@ struct ntb_device {
unsigned char link_width;
unsigned char link_speed;
unsigned char link_status;
unsigned char split_bar;
struct delayed_work hb_timer;
unsigned long last_ts;

31
drivers/ntb/ntb_regs.h
View file

@ -57,6 +57,7 @@
#define SNB_MAX_DB_BITS 15
#define SNB_LINK_DB 15
#define SNB_DB_BITS_PER_VEC 5
#define HSX_SPLITBAR_MAX_MW 3
#define SNB_MAX_MW 2
#define SNB_ERRATA_MAX_MW 1
@ -72,15 +73,20 @@
#define SNB_PBAR2LMT_OFFSET 0x0000
#define SNB_PBAR4LMT_OFFSET 0x0008
#define SNB_PBAR5LMT_OFFSET 0x000C
#define SNB_PBAR2XLAT_OFFSET 0x0010
#define SNB_PBAR4XLAT_OFFSET 0x0018
#define SNB_PBAR5XLAT_OFFSET 0x001C
#define SNB_SBAR2LMT_OFFSET 0x0020
#define SNB_SBAR4LMT_OFFSET 0x0028
#define SNB_SBAR5LMT_OFFSET 0x002C
#define SNB_SBAR2XLAT_OFFSET 0x0030
#define SNB_SBAR4XLAT_OFFSET 0x0038
#define SNB_SBAR5XLAT_OFFSET 0x003C
#define SNB_SBAR0BASE_OFFSET 0x0040
#define SNB_SBAR2BASE_OFFSET 0x0048
#define SNB_SBAR4BASE_OFFSET 0x0050
#define SNB_SBAR5BASE_OFFSET 0x0054
#define SNB_NTBCNTL_OFFSET 0x0058
#define SNB_SBDF_OFFSET 0x005C
#define SNB_PDOORBELL_OFFSET 0x0060
@ -96,12 +102,18 @@
#define SNB_B2B_XLAT_OFFSETL 0x0144
#define SNB_B2B_XLAT_OFFSETU 0x0148
#define SNB_MBAR01_USD_ADDR 0x000000210000000CULL
#define SNB_MBAR23_USD_ADDR 0x000000410000000CULL
#define SNB_MBAR45_USD_ADDR 0x000000810000000CULL
#define SNB_MBAR01_DSD_ADDR 0x000000200000000CULL
#define SNB_MBAR23_DSD_ADDR 0x000000400000000CULL
#define SNB_MBAR45_DSD_ADDR 0x000000800000000CULL
/*
* The addresses are setup so the 32bit BARs can function. Thus
* the addresses are all in 32bit space
*/
#define SNB_MBAR01_USD_ADDR 0x000000002100000CULL
#define SNB_MBAR23_USD_ADDR 0x000000004100000CULL
#define SNB_MBAR4_USD_ADDR 0x000000008100000CULL
#define SNB_MBAR5_USD_ADDR 0x00000000A100000CULL
#define SNB_MBAR01_DSD_ADDR 0x000000002000000CULL
#define SNB_MBAR23_DSD_ADDR 0x000000004000000CULL
#define SNB_MBAR4_DSD_ADDR 0x000000008000000CULL
#define SNB_MBAR5_DSD_ADDR 0x00000000A000000CULL
#define BWD_MSIX_CNT 34
#define BWD_MAX_SPADS 16
@ -150,13 +162,16 @@
#define NTB_CNTL_LINK_DISABLE (1 << 1)
#define NTB_CNTL_S2P_BAR23_SNOOP (1 << 2)
#define NTB_CNTL_P2S_BAR23_SNOOP (1 << 4)
#define NTB_CNTL_S2P_BAR45_SNOOP (1 << 6)
#define NTB_CNTL_P2S_BAR45_SNOOP (1 << 8)
#define NTB_CNTL_S2P_BAR4_SNOOP (1 << 6)
#define NTB_CNTL_P2S_BAR4_SNOOP (1 << 8)
#define NTB_CNTL_S2P_BAR5_SNOOP (1 << 12)
#define NTB_CNTL_P2S_BAR5_SNOOP (1 << 14)
#define BWD_CNTL_LINK_DOWN (1 << 16)
#define NTB_PPD_OFFSET 0x00D4
#define SNB_PPD_CONN_TYPE 0x0003
#define SNB_PPD_DEV_TYPE 0x0010
#define SNB_PPD_SPLIT_BAR (1 << 6)
#define BWD_PPD_INIT_LINK 0x0008
#define BWD_PPD_CONN_TYPE 0x0300
#define BWD_PPD_DEV_TYPE 0x1000