[PATCH V2] cxl: Export library to support IBM XSL
Andrew Donnellan
andrew.donnellan at au1.ibm.com
Fri Jun 16 17:13:03 AEST 2017
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 <clombard at linux.vnet.ibm.com>
For the parts of this I wrote:
Signed-off-by: Andrew Donnellan <andrew.donnellan at 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.donnellan at au1.ibm.com IBM Australia Limited
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