On 14/06/17 23:29, Christophe Lombard wrote:
This patch exports a in-kernel 'library' API which can be called by
other drivers to help interacting with an IBM XSL on a POWER9 system.
The XSL (Translation Service Layer) is a stripped down version of the
PSL (Power Service Layer) used in some cards such as the Mellanox CX5.
Like the PSL, it implements the CAIA architecture, but has a number
of differences, mostly in it's implementation dependent registers.
The XSL also uses a special DMA cxl mode, which uses a slightly
different init sequence for the CAPP and PHB.
Changelog[v2]
- Rebase to latest upstream.
- Return -EFAULT in case of NULL pointer in cxllib_handle_fault().
- Reverse parameters when copro_handle_mm_fault() is called.
Signed-off-by: Christophe Lombard <clomb...@linux.vnet.ibm.com>
For the parts of this I wrote:
Signed-off-by: Andrew Donnellan <andrew.donnel...@au1.ibm.com>
I'll skip the comments that Fred's already made, some minor comments below.
---
This applies on top of this patch:
http://patchwork.ozlabs.org/patch/775322/
---
arch/powerpc/include/asm/opal-api.h | 1 +
drivers/misc/cxl/Kconfig | 5 +
drivers/misc/cxl/Makefile | 2 +-
drivers/misc/cxl/cxl.h | 7 ++
drivers/misc/cxl/cxllib.c | 241 ++++++++++++++++++++++++++++++++++++
drivers/misc/cxl/fault.c | 25 ++--
drivers/misc/cxl/native.c | 16 ++-
drivers/misc/cxl/pci.c | 41 +++---
include/misc/cxllib.h | 132 ++++++++++++++++++++
9 files changed, 439 insertions(+), 31 deletions(-)
create mode 100644 drivers/misc/cxl/cxllib.c
create mode 100644 include/misc/cxllib.h
diff --git a/arch/powerpc/include/asm/opal-api.h
b/arch/powerpc/include/asm/opal-api.h
index cb3e624..3e0be78 100644
--- a/arch/powerpc/include/asm/opal-api.h
+++ b/arch/powerpc/include/asm/opal-api.h
@@ -877,6 +877,7 @@ enum {
OPAL_PHB_CAPI_MODE_SNOOP_OFF = 2,
OPAL_PHB_CAPI_MODE_SNOOP_ON = 3,
OPAL_PHB_CAPI_MODE_DMA = 4,
+ OPAL_PHB_CAPI_MODE_DMA_TVT1 = 5,
};
/* OPAL I2C request */
diff --git a/drivers/misc/cxl/Kconfig b/drivers/misc/cxl/Kconfig
index b75cf83..93397cb 100644
--- a/drivers/misc/cxl/Kconfig
+++ b/drivers/misc/cxl/Kconfig
@@ -11,11 +11,16 @@ config CXL_AFU_DRIVER_OPS
bool
default n
+config CXL_LIB
+ bool
+ default n
+
How necessary is this? Are there any drivers using cxllib that we're
trying to get in during this cycle?
config CXL
tristate "Support for IBM Coherent Accelerators (CXL)"
depends on PPC_POWERNV && PCI_MSI && EEH
select CXL_BASE
select CXL_AFU_DRIVER_OPS
+ select CXL_LIB
default m
help
Select this option to enable driver support for IBM Coherent
diff --git a/drivers/misc/cxl/Makefile b/drivers/misc/cxl/Makefile
index c14fd6b..0b5fd74 100644
--- a/drivers/misc/cxl/Makefile
+++ b/drivers/misc/cxl/Makefile
@@ -3,7 +3,7 @@ ccflags-$(CONFIG_PPC_WERROR) += -Werror
cxl-y += main.o file.o irq.o fault.o native.o
cxl-y += context.o sysfs.o pci.o trace.o
-cxl-y += vphb.o phb.o api.o
+cxl-y += vphb.o phb.o api.o cxllib.o
cxl-$(CONFIG_PPC_PSERIES) += flash.o guest.o of.o hcalls.o
cxl-$(CONFIG_DEBUG_FS) += debugfs.o
obj-$(CONFIG_CXL) += cxl.o
diff --git a/drivers/misc/cxl/cxl.h b/drivers/misc/cxl/cxl.h
index a03f8e7..81e01f0 100644
--- a/drivers/misc/cxl/cxl.h
+++ b/drivers/misc/cxl/cxl.h
@@ -1010,6 +1010,8 @@ static inline void cxl_debugfs_add_afu_regs_psl8(struct
cxl_afu *afu, struct den
void cxl_handle_fault(struct work_struct *work);
void cxl_prefault(struct cxl_context *ctx, u64 wed);
+int cxl_handle_page_fault(bool kernel_context, struct mm_struct *mm,
+ u64 dsisr, u64 dar);
struct cxl *get_cxl_adapter(int num);
int cxl_alloc_sst(struct cxl_context *ctx);
@@ -1061,6 +1063,11 @@ int cxl_afu_slbia(struct cxl_afu *afu);
int cxl_data_cache_flush(struct cxl *adapter);
int cxl_afu_disable(struct cxl_afu *afu);
int cxl_psl_purge(struct cxl_afu *afu);
+int cxl_calc_capp_routing(struct pci_dev *dev, u64 *chipid,
+ u32 *phb_index, u64 *capp_unit_id);
+int cxl_slot_is_switched(struct pci_dev *dev);
+int cxl_get_xsl9_dsnctl(u64 capp_unit_id, u64 *reg);
+u64 cxl_calculate_sr(bool master, bool kernel, bool real_mode, bool p9);
void cxl_native_irq_dump_regs_psl9(struct cxl_context *ctx);
void cxl_native_irq_dump_regs_psl8(struct cxl_context *ctx);
diff --git a/drivers/misc/cxl/cxllib.c b/drivers/misc/cxl/cxllib.c
new file mode 100644
index 0000000..63b6280
--- /dev/null
+++ b/drivers/misc/cxl/cxllib.c
@@ -0,0 +1,241 @@
+/*
+ * Copyright 2016 IBM Corp.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/hugetlb.h>
+#include <linux/sched/mm.h>
+#include "cxl.h"
+#include <misc/cxllib.h>
+#include <asm/pnv-pci.h>
+
+#define CXL_INVALID_DRA ~0ull
+#define CXL_DUMMY_READ_SIZE 128
+#define CXL_DUMMY_READ_ALIGN 8
+#define CXL_CAPI_WINDOW_START 0x2000000000000ull
+#define CXL_CAPI_WINDOW_LOG_SIZE 48
+#define CXL_XSL_CONFIG_CURRENT_VERSION CXL_XSL_CONFIG_VERSION1
+
+
+bool cxllib_slot_is_supported(struct pci_dev *dev, unsigned long flags)
+{
+ int rc;
+ u32 phb_index;
+ u64 chip_id, capp_unit_id;
+
+ /* Currently none supported */
"No flags currently supported" would be clearer
+ if (flags)
+ return false;
+
+ if (!cpu_has_feature(CPU_FTR_HVMODE))
+ return false;
+
+ if (!cxl_is_power9())
+ return false;
+
+ if (cxl_slot_is_switched(dev))
+ return false;
+
+ /* on p9, some pci slots are not connected to a CAPP unit */
+ rc = cxl_calc_capp_routing(dev, &chip_id, &phb_index, &capp_unit_id);
+ if (rc)
+ return false;
+
+ return true;
+}
+EXPORT_SYMBOL_GPL(cxllib_slot_is_supported);
+
+static DEFINE_MUTEX(dra_mutex);
+static u64 dummy_read_addr = CXL_INVALID_DRA;
+
+int allocate_dummy_read_buf(void)
static?
+{
+ u64 buf, vaddr;
+ size_t buf_size;
+
+ /*
+ * Dummy read buffer is 128-byte long, aligned on a
+ * 256-byte boundary and we need the physical address.
+ */
+ buf_size = CXL_DUMMY_READ_SIZE + (1ull << CXL_DUMMY_READ_ALIGN);
+ buf = (u64) kzalloc(buf_size, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ vaddr = (buf + (1ull << CXL_DUMMY_READ_ALIGN) - 1) &
+ (~0ull << CXL_DUMMY_READ_ALIGN);
+
+ WARN((vaddr + CXL_DUMMY_READ_SIZE) > (buf + buf_size),
+ "Dummy read buffer alignment issue");
+ dummy_read_addr = virt_to_phys((void *) vaddr);
+ return 0;
+}
+
+int cxllib_get_xsl_config(struct pci_dev *dev, struct cxllib_xsl_config *cfg)
+{
+ int rc;
+ u32 phb_index;
+ u64 chip_id, capp_unit_id;
+
+ if (!cpu_has_feature(CPU_FTR_HVMODE))
+ return -EINVAL;
+
+ mutex_lock(&dra_mutex);
+ if (dummy_read_addr == CXL_INVALID_DRA) {
+ rc = allocate_dummy_read_buf();
+ if (rc) {
+ mutex_unlock(&dra_mutex);
+ return rc;
+ }
+ }
+ mutex_unlock(&dra_mutex);
+
+ rc = cxl_calc_capp_routing(dev, &chip_id, &phb_index, &capp_unit_id);
+ if (rc)
+ return rc;
+
+ rc = cxl_get_xsl9_dsnctl(capp_unit_id, &cfg->dsnctl);
+ if (rc)
+ return rc;
+ if (cpu_has_feature(CPU_FTR_POWER9_DD1)) {
+ /* workaround for DD1 - nbwind = capiind */
+ cfg->dsnctl |= ((u64)0x02 << (63-47));
+ }
+
+ cfg->version = CXL_XSL_CONFIG_CURRENT_VERSION;
+ cfg->log_bar_size = CXL_CAPI_WINDOW_LOG_SIZE;
+ cfg->bar_addr = CXL_CAPI_WINDOW_START;
+ cfg->dra = dummy_read_addr;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(cxllib_get_xsl_config);
+
+
+int cxllib_switch_phb_mode(struct pci_dev *dev, enum cxllib_mode mode,
+ unsigned long flags)
+{
+ int rc = 0;
+
+ if (!cpu_has_feature(CPU_FTR_HVMODE))
+ return -EINVAL;
+
+ switch (mode) {
+ case CXL_MODE_PCI:
+ /*
+ * We currently don't support going back to PCI mode
+ * However, we'll turn the invalidations off, so that
+ * the CX5 firmware doesn't have to ack them and can do
+ * things like reset, etc.. with no worries.
+ * So always return EPERM (can't go back to PCI) or
+ * EBUSY if we couldn't even turn off snooping
+ */
This comment shouldn't be CX5 specific
+ rc = pnv_phb_to_cxl_mode(dev, OPAL_PHB_CAPI_MODE_SNOOP_OFF);
+ if (rc)
+ rc = -EBUSY;
+ else
+ rc = -EPERM;
+ break;
+ case CXL_MODE_CXL:
+ /* DMA only supported on TVT1 for the time being */
+ if (flags != CXL_MODE_DMA_TVT1)
+ return -EINVAL;
+ rc = pnv_phb_to_cxl_mode(dev, OPAL_PHB_CAPI_MODE_DMA_TVT1);
+ if (rc)
+ return rc;
+ rc = pnv_phb_to_cxl_mode(dev, OPAL_PHB_CAPI_MODE_SNOOP_ON);
+ break;
+ default:
+ rc = -EINVAL;
+ }
+ return rc;
+}
+EXPORT_SYMBOL_GPL(cxllib_switch_phb_mode);
+
+
+int cxllib_set_device_dma(struct pci_dev *dev, unsigned long flags)
+{
+ int rc;
+
+ if (flags)
+ return -EINVAL;
+
+ rc = dma_set_mask(&dev->dev, DMA_BIT_MASK(64));
+ return rc;
+}
+EXPORT_SYMBOL_GPL(cxllib_set_device_dma);
+
+
+int cxllib_get_PE_attributes(struct task_struct *task,
+ unsigned long translation_mode, struct cxllib_pe_attributes *attr)
+{
+ struct mm_struct *mm = NULL;
+
+ if (translation_mode != CXL_TRANSLATED_MODE &&
+ translation_mode != CXL_REAL_MODE)
+ return -EINVAL;
+
+ attr->sr = cxl_calculate_sr(false /* master */,
+ task == NULL /* kernel ctx */,
+ translation_mode == CXL_REAL_MODE,
+ true /* p9 */);
nitpicking: comments in the middle of a line feels slightly ugly to me :)
+ attr->lpid = mfspr(SPRN_LPID);
+ if (task) {
+ mm = get_task_mm(task);
+ if (mm == NULL)
+ return -EINVAL;
+ /*
+ * Caller is keeping a reference on mm_users for as long
+ * as XSL uses the memory context
+ */
+ attr->pid = mm->context.id;
+ mmput(mm);
+ } else {
+ attr->pid = 0;
+ }
+ attr->tid = 0;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(cxllib_get_PE_attributes);
+
+
+int cxllib_handle_fault(struct mm_struct *mm, u64 addr, u64 size, u64 flags)
+{
+ int rc;
+ u64 dar;
+ struct vm_area_struct *vma = NULL;
+ unsigned long page_size;
+
+ if (mm == NULL)
+ return -EFAULT;
+
+ down_read(&mm->mmap_sem);
+
+ for (dar = addr; dar < addr + size; dar += page_size) {
+ if (!vma || dar < vma->vm_start || dar > vma->vm_end) {
+ vma = find_vma(mm, addr);
+ if (!vma) {
+ pr_err("Can't find vma for addr %016llx\n",
addr);
+ rc = -EFAULT;
+ goto out;
+ }
+ /* get the size of the pages allocated */
+ page_size = vma_kernel_pagesize(vma);
+ }
+
+ rc = cxl_handle_page_fault(true, mm, flags, dar);
+ if (rc) {
+ pr_err("_cxl_handle_page_fault failed %d", rc);
Get rid of the initial underscore, that's just left over from an early
version of this code
+ rc = -EFAULT;
+ goto out;
+ }
+ }
+ rc = 0;
+out:
+ up_read(&mm->mmap_sem);
+ return rc;
+}
+EXPORT_SYMBOL_GPL(cxllib_handle_fault);
diff --git a/drivers/misc/cxl/fault.c b/drivers/misc/cxl/fault.c
index c79e39b..9db63f3 100644
--- a/drivers/misc/cxl/fault.c
+++ b/drivers/misc/cxl/fault.c
@@ -132,18 +132,16 @@ static int cxl_handle_segment_miss(struct cxl_context
*ctx,
return IRQ_HANDLED;
}
-static void cxl_handle_page_fault(struct cxl_context *ctx,
- struct mm_struct *mm, u64 dsisr, u64 dar)
+int cxl_handle_page_fault(bool kernel_context,
+ struct mm_struct *mm, u64 dsisr, u64 dar)
If we don't get rid of kernel_context per Fred, it would look cleaner to
move it to the end of the argument list.
{
unsigned flt = 0;
int result;
unsigned long access, flags, inv_flags = 0;
- trace_cxl_pte_miss(ctx, dsisr, dar);
-
if ((result = copro_handle_mm_fault(mm, dar, dsisr, &flt))) {
pr_devel("copro_handle_mm_fault failed: %#x\n", result);
- return cxl_ack_ae(ctx);
+ return result;
}
if (!radix_enabled()) {
@@ -156,7 +154,7 @@ static void cxl_handle_page_fault(struct cxl_context *ctx,
access |= _PAGE_WRITE;
access |= _PAGE_PRIVILEGED;
- if ((!ctx->kernel) || (REGION_ID(dar) == USER_REGION_ID))
+ if (!kernel_context || (REGION_ID(dar) == USER_REGION_ID))
access &= ~_PAGE_PRIVILEGED;
While we're here...
if (kernel_context && (REGION_ID(dar) != USER_REGION_ID))
access |= _PAGE_PRIVILEGED;
if (dsisr & DSISR_NOHPTE)
@@ -166,8 +164,7 @@ static void cxl_handle_page_fault(struct cxl_context *ctx,
hash_page_mm(mm, dar, access, 0x300, inv_flags);
local_irq_restore(flags);
}
- pr_devel("Page fault successfully handled for pe: %i!\n", ctx->pe);
- cxl_ops->ack_irq(ctx, CXL_PSL_TFC_An_R, 0);
+ return 0;
}
/*
@@ -261,9 +258,15 @@ void cxl_handle_fault(struct work_struct *fault_work)
if (cxl_is_segment_miss(ctx, dsisr))
cxl_handle_segment_miss(ctx, mm, dar);
- else if (cxl_is_page_fault(ctx, dsisr))
- cxl_handle_page_fault(ctx, mm, dsisr, dar);
- else
+ else if (cxl_is_page_fault(ctx, dsisr)) {
+ trace_cxl_pte_miss(ctx, dsisr, dar);
+ if (cxl_handle_page_fault(ctx->kernel, mm, dsisr, dar)) {
+ cxl_ack_ae(ctx);
+ } else {
+ pr_devel("Page fault successfully handled for pe: %i!\n",
ctx->pe);
+ cxl_ops->ack_irq(ctx, CXL_PSL_TFC_An_R, 0);
+ }
+ } else
WARN(1, "cxl_handle_fault has nothing to handle\n");
if (mm)
diff --git a/drivers/misc/cxl/native.c b/drivers/misc/cxl/native.c
index 2b2f889..4a82c31 100644
--- a/drivers/misc/cxl/native.c
+++ b/drivers/misc/cxl/native.c
@@ -586,17 +586,17 @@ static int activate_afu_directed(struct cxl_afu *afu)
#define set_endian(sr) ((sr) &= ~(CXL_PSL_SR_An_LE))
#endif
-static u64 calculate_sr(struct cxl_context *ctx)
+u64 cxl_calculate_sr(bool master, bool kernel, bool real_mode, bool p9)
{
u64 sr = 0;
set_endian(sr);
- if (ctx->master)
+ if (master)
sr |= CXL_PSL_SR_An_MP;
if (mfspr(SPRN_LPCR) & LPCR_TC)
sr |= CXL_PSL_SR_An_TC;
- if (ctx->kernel) {
- if (!ctx->real_mode)
+ if (kernel) {
+ if (!real_mode)
sr |= CXL_PSL_SR_An_R;
sr |= (mfmsr() & MSR_SF) | CXL_PSL_SR_An_HV;
} else {
@@ -608,7 +608,7 @@ static u64 calculate_sr(struct cxl_context *ctx)
if (!test_tsk_thread_flag(current, TIF_32BIT))
sr |= CXL_PSL_SR_An_SF;
}
- if (cxl_is_power9()) {
+ if (p9) {
if (radix_enabled())
sr |= CXL_PSL_SR_An_XLAT_ror;
else
@@ -617,6 +617,12 @@ static u64 calculate_sr(struct cxl_context *ctx)
return sr;
}
+static u64 calculate_sr(struct cxl_context *ctx)
+{
+ return cxl_calculate_sr(ctx->master, ctx->kernel, ctx->real_mode,
+ cxl_is_power9());
+}
+
static void update_ivtes_directed(struct cxl_context *ctx)
{
bool need_update = (ctx->status == STARTED);
diff --git a/drivers/misc/cxl/pci.c b/drivers/misc/cxl/pci.c
index 1eb9859..d18b3d9 100644
--- a/drivers/misc/cxl/pci.c
+++ b/drivers/misc/cxl/pci.c
@@ -375,7 +375,7 @@ static u64 get_capp_unit_id(struct device_node *np, u32
phb_index)
return 0;
}
-static int calc_capp_routing(struct pci_dev *dev, u64 *chipid,
+int cxl_calc_capp_routing(struct pci_dev *dev, u64 *chipid,
u32 *phb_index, u64 *capp_unit_id)
{
int rc;
@@ -408,17 +408,9 @@ static int calc_capp_routing(struct pci_dev *dev, u64
*chipid,
return 0;
}
-static int init_implementation_adapter_regs_psl9(struct cxl *adapter, struct
pci_dev *dev)
+int cxl_get_xsl9_dsnctl(u64 capp_unit_id, u64 *reg)
{
- u64 xsl_dsnctl, psl_fircntl;
- u64 chipid;
- u32 phb_index;
- u64 capp_unit_id;
- int rc;
-
- rc = calc_capp_routing(dev, &chipid, &phb_index, &capp_unit_id);
- if (rc)
- return rc;
+ u64 xsl_dsnctl;
/*
* CAPI Identifier bits [0:7]
@@ -454,6 +446,27 @@ static int init_implementation_adapter_regs_psl9(struct
cxl *adapter, struct pci
xsl_dsnctl |= ((u64)0x04 << (63-55));
}
+ *reg = xsl_dsnctl;
+ return 0;
+}
+
+static int init_implementation_adapter_regs_psl9(struct cxl *adapter,
+ struct pci_dev *dev)
+{
+ u64 xsl_dsnctl, psl_fircntl;
+ u64 chipid;
+ u32 phb_index;
+ u64 capp_unit_id;
+ int rc;
+
+ rc = cxl_calc_capp_routing(dev, &chipid, &phb_index, &capp_unit_id);
+ if (rc)
+ return rc;
+
+ rc = cxl_get_xsl9_dsnctl(capp_unit_id, &xsl_dsnctl);
+ if (rc)
+ return rc;
+
cxl_p1_write(adapter, CXL_XSL9_DSNCTL, xsl_dsnctl);
/* Set fir_cntl to recommended value for production env */
@@ -505,7 +518,7 @@ static int init_implementation_adapter_regs_psl8(struct cxl
*adapter, struct pci
u64 capp_unit_id;
int rc;
- rc = calc_capp_routing(dev, &chipid, &phb_index, &capp_unit_id);
+ rc = cxl_calc_capp_routing(dev, &chipid, &phb_index, &capp_unit_id);
if (rc)
return rc;
@@ -538,7 +551,7 @@ static int init_implementation_adapter_regs_xsl(struct cxl
*adapter, struct pci_
u64 capp_unit_id;
int rc;
- rc = calc_capp_routing(dev, &chipid, &phb_index, &capp_unit_id);
+ rc = cxl_calc_capp_routing(dev, &chipid, &phb_index, &capp_unit_id);
if (rc)
return rc;
@@ -1897,7 +1910,7 @@ static void cxl_pci_remove_adapter(struct cxl *adapter)
#define CXL_MAX_PCIEX_PARENT 2
-static int cxl_slot_is_switched(struct pci_dev *dev)
+int cxl_slot_is_switched(struct pci_dev *dev)
{
struct device_node *np;
int depth = 0;
diff --git a/include/misc/cxllib.h b/include/misc/cxllib.h
new file mode 100644
index 0000000..d2f3358
--- /dev/null
+++ b/include/misc/cxllib.h
@@ -0,0 +1,132 @@
+/*
+ * Copyright 2016 IBM Corp.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#ifndef _MISC_CXLLIB_H
+#define _MISC_CXLLIB_H
+
+#include <linux/pci.h>
+#include <asm/reg.h>
+
+/*
+ * cxl driver exports a in-kernel 'library' API which can be called by
+ * other drivers to help interacting with an IBM XSL.
+ */
+
+/*
+ * tells whether capi is supported on the PCIe slot where the
+ * device is seated
+ *
+ * Input:
+ * dev: device whose slot needs to be checked
+ * flags: 0 for the time being
+ */
+bool cxllib_slot_is_supported(struct pci_dev *dev, unsigned long flags);
+
+
+/*
+ * Returns the configuration parameters to be used by the XSL or device
+ *
+ * Input:
+ * dev: device, used to find PHB
+ * Output:
+ * struct cxllib_xsl_config:
+ * version
+ * capi BAR address, i.e. 0x2000000000000-0x2FFFFFFFFFFFF
+ * capi BAR size
+ * data send control (XSL_DSNCTL)
+ * dummy read address (XSL_DRA)
+ */
+#define CXL_XSL_CONFIG_VERSION1 1
+struct cxllib_xsl_config {
+ u32 version; /* format version for register encoding */
+ u32 log_bar_size;/* log size of the capi_window */
+ u64 bar_addr; /* address of the start of capi window */
+ u64 dsnctl; /* matches definition of XSL_DSNCTL */
+ u64 dra; /* real address that can be used for dummy read */
+};
+
+int cxllib_get_xsl_config(struct pci_dev *dev, struct cxllib_xsl_config *cfg);
+
+
+/*
+ * Activate capi for the pci host bridge associated with the device.
+ * Can be extended to deactivate once we know how to do it.
+ * Device must be ready to accept messages from the CAPP unit and
+ * respond accordingly (TLB invalidates, ...)
+ *
+ * PHB is switched to capi mode through calls to skiboot.
+ * CAPP snooping is activated
+ *
+ * Input:
+ * dev: device whose PHB should switch mode
+ * mode: mode to switch to i.e. CAPI or PCI
+ * flags: options related to the mode
+ */
+enum cxllib_mode {
+ CXL_MODE_CXL,
+ CXL_MODE_PCI,
+};
+
+#define CXL_MODE_NO_DMA 0
+#define CXL_MODE_DMA_TVT0 1
+#define CXL_MODE_DMA_TVT1 2
+
+int cxllib_switch_phb_mode(struct pci_dev *dev, enum cxllib_mode mode,
+ unsigned long flags);
+
+
+/*
+ * Set the device for capi DMA.
+ * Define its dma_ops and dma offset so that allocations will be using TVT#1
+ *
+ * Input:
+ * dev: device to set
+ * flags: options. CXL_MODE_DMA_TVT1 should be used
+ */
+int cxllib_set_device_dma(struct pci_dev *dev, unsigned long flags);
+
+
+
+/*
+ * Get the Process Element structure for the given thread
+ *
+ * Input:
+ * pid: points the struct pid for the given thread (i.e. linux pid)
+ * translation_mode: whether addresses should be translated
+ */
+struct cxllib_pe_attributes {
+ u64 sr;
+ u32 lpid;
+ u32 tid;
+ u32 pid;
+};
+#define CXL_TRANSLATED_MODE 0
+#define CXL_REAL_MODE 1
+
+int cxllib_get_PE_attributes(struct task_struct *task,
+ unsigned long translation_mode, struct cxllib_pe_attributes *attr);
+
+
+/*
+ * Handle memory fault.
+ * Fault in all the pages of the specified buffer for the permissions
+ * provided in ‘flags’
+ *
+ * Shouldn't be called from interrupt context
+ *
+ * Input:
+ * mm: struct mm for the thread faulting the pages
+ * addr: base address of the buffer to page in
+ * size: size of the buffer to page in
+ * flags: permission requested (DSISR_ISSTORE...)
+ */
+int cxllib_handle_fault(struct mm_struct *mm, u64 addr, u64 size, u64 flags);
+
+
+#endif /* _MISC_CXLLIB_H */
--
Andrew Donnellan OzLabs, ADL Canberra
andrew.donnel...@au1.ibm.com IBM Australia Limited