@@ -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 */
@@ -11,11 +11,16 @@ config CXL_AFU_DRIVER_OPS
bool
default n
+config CXL_LIB
+ bool
+ default n
+
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
@@ -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
@@ -1010,6 +1010,7 @@ 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_mm_fault(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 +1062,11 @@ 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);
new file mode 100644
@@ -0,0 +1,246 @@
+/*
+ * Copyright 2017 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 <asm/pnv-pci.h>
+#include <linux/hugetlb.h>
+#include <linux/sched/mm.h>
+#include <misc/cxllib.h>
+
+#include "cxl.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;
+
+ /* No flags currently supported */
+ 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;
+
+static int allocate_dummy_read_buf(void)
+{
+ 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 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
+ */
+ 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);
+
+/*
+ * When switching the PHB to capi mode, the TVT#1 entry for
+ * the Partitionable Endpoint is set in bypass mode, like
+ * in PCI mode.
+ * Configure the device dma to use TVT#1, which is done
+ * by calling dma_set_mask() with a mask large enough.
+ */
+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,
+ task == NULL,
+ translation_mode == CXL_REAL_MODE,
+ true);
+ 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_mm_fault(mm, flags, dar);
+ if (rc) {
+ pr_err("cxl_handle_mm_fault failed %d", rc);
+ rc = -EFAULT;
+ goto out;
+ }
+ }
+ rc = 0;
+out:
+ up_read(&mm->mmap_sem);
+ return rc;
+}
+EXPORT_SYMBOL_GPL(cxllib_handle_fault);
@@ -132,18 +132,15 @@ 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_mm_fault(struct mm_struct *mm, u64 dsisr, u64 dar)
{
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 +153,7 @@ 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 (mm || (REGION_ID(dar) == USER_REGION_ID))
access &= ~_PAGE_PRIVILEGED;
if (dsisr & DSISR_NOHPTE)
@@ -166,8 +163,23 @@ 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;
+}
+
+static int cxl_handle_page_fault(struct cxl_context *ctx,
+ struct mm_struct *mm,
+ u64 dsisr, u64 dar)
+{
+ trace_cxl_pte_miss(ctx, dsisr, dar);
+
+ if (cxl_handle_mm_fault(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);
+ }
+
+ return IRQ_HANDLED;
}
/*
@@ -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);
@@ -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;
new file mode 100644
@@ -0,0 +1,133 @@
+/*
+ * Copyright 2017 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:
+ * task: task_struct for the context of the translation
+ * translation_mode: whether addresses should be translated
+ * Output:
+ * attr: attributes to fill up the Process Element structure from CAIA
+ */
+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 */
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. Signed-off-by: Christophe Lombard <clombard@linux.vnet.ibm.com> --- Changelog[v3] - Rebase to latest upstream. - cxl_handle_mm_fault() is now exported. Remove kernel context parameter - Update comments 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. --- arch/powerpc/include/asm/opal-api.h | 1 + drivers/misc/cxl/Kconfig | 5 + drivers/misc/cxl/Makefile | 2 +- drivers/misc/cxl/cxl.h | 6 + drivers/misc/cxl/cxllib.c | 246 ++++++++++++++++++++++++++++++++++++ drivers/misc/cxl/fault.c | 28 ++-- drivers/misc/cxl/native.c | 16 ++- drivers/misc/cxl/pci.c | 41 ++++-- include/misc/cxllib.h | 133 +++++++++++++++++++ 9 files changed, 450 insertions(+), 28 deletions(-) create mode 100644 drivers/misc/cxl/cxllib.c create mode 100644 include/misc/cxllib.h