P9 supports PCI tunneled operations (atomics and as_notify). This patch adds support for tunneled operations on powernv, with a new API, to be called by device drivers:
pnv_pci_get_tunnel_ind() Tell driver the 16-bit ASN indication used by kernel. pnv_pci_set_tunnel_bar() Tell kernel the Tunnel BAR Response address used by driver. This function uses two new OPAL calls, as the PBCQ Tunnel BAR register is configured by skiboot. pnv_pci_get_as_notify_info() Return the ASN info of the thread to be woken up. Signed-off-by: Philippe Bergheaud <fe...@linux.vnet.ibm.com> --- Changelog: v2: Do not set the ASN indication. Get it from the device tree. v3: Make pnv_pci_get_phb_node() available when compiling without cxl. v4: Add pnv_pci_get_as_notify_info(). Rebase opal call numbers on skiboot 5.9.6. v5: pnv_pci_get_tunnel_ind(): - fix node reference count pnv_pci_get_as_notify_info(): - fail if task == NULL - read pid from mm->context.id - explain that thread.tidr require CONFIG_PPC64 v6: pnv_pci_get_tunnel_ind(): - check if radix is enabled, or else return an error pnv_pci_get_as_notify_info(): - remove a capi-specific comment, irrelevant for pci v7: pnv_pci_set_tunnel_bar(): - setting the tunnel bar more than once with the same value is not an error v8: No change This patch depends on the following skiboot patches: https://patchwork.ozlabs.org/patch/858324/ https://patchwork.ozlabs.org/patch/858325/ --- arch/powerpc/include/asm/opal-api.h | 4 +- arch/powerpc/include/asm/opal.h | 2 + arch/powerpc/include/asm/pnv-pci.h | 5 ++ arch/powerpc/platforms/powernv/opal-wrappers.S | 2 + arch/powerpc/platforms/powernv/pci-cxl.c | 8 -- arch/powerpc/platforms/powernv/pci.c | 107 +++++++++++++++++++++++++ 6 files changed, 119 insertions(+), 9 deletions(-) diff --git a/arch/powerpc/include/asm/opal-api.h b/arch/powerpc/include/asm/opal-api.h index 233c7504b1f2..b901f4d9f009 100644 --- a/arch/powerpc/include/asm/opal-api.h +++ b/arch/powerpc/include/asm/opal-api.h @@ -201,7 +201,9 @@ #define OPAL_SET_POWER_SHIFT_RATIO 155 #define OPAL_SENSOR_GROUP_CLEAR 156 #define OPAL_PCI_SET_P2P 157 -#define OPAL_LAST 157 +#define OPAL_PCI_GET_PBCQ_TUNNEL_BAR 159 +#define OPAL_PCI_SET_PBCQ_TUNNEL_BAR 160 +#define OPAL_LAST 160 /* Device tree flags */ diff --git a/arch/powerpc/include/asm/opal.h b/arch/powerpc/include/asm/opal.h index 0c545f7fc77b..8705e422b893 100644 --- a/arch/powerpc/include/asm/opal.h +++ b/arch/powerpc/include/asm/opal.h @@ -198,6 +198,8 @@ int64_t opal_unregister_dump_region(uint32_t id); int64_t opal_slw_set_reg(uint64_t cpu_pir, uint64_t sprn, uint64_t val); int64_t opal_config_cpu_idle_state(uint64_t state, uint64_t flag); int64_t opal_pci_set_phb_cxl_mode(uint64_t phb_id, uint64_t mode, uint64_t pe_number); +int64_t opal_pci_get_pbcq_tunnel_bar(uint64_t phb_id, uint64_t *addr); +int64_t opal_pci_set_pbcq_tunnel_bar(uint64_t phb_id, uint64_t addr); int64_t opal_ipmi_send(uint64_t interface, struct opal_ipmi_msg *msg, uint64_t msg_len); int64_t opal_ipmi_recv(uint64_t interface, struct opal_ipmi_msg *msg, diff --git a/arch/powerpc/include/asm/pnv-pci.h b/arch/powerpc/include/asm/pnv-pci.h index 3e5cf251ad9a..c69de3276b5e 100644 --- a/arch/powerpc/include/asm/pnv-pci.h +++ b/arch/powerpc/include/asm/pnv-pci.h @@ -29,6 +29,11 @@ extern int pnv_pci_set_power_state(uint64_t id, uint8_t state, extern int pnv_pci_set_p2p(struct pci_dev *initiator, struct pci_dev *target, u64 desc); +extern int pnv_pci_get_tunnel_ind(struct pci_dev *dev, uint64_t *ind); +extern int pnv_pci_set_tunnel_bar(struct pci_dev *dev, uint64_t addr, + int enable); +extern int pnv_pci_get_as_notify_info(struct task_struct *task, u32 *lpid, + u32 *pid, u32 *tid); int pnv_phb_to_cxl_mode(struct pci_dev *dev, uint64_t mode); int pnv_cxl_ioda_msi_setup(struct pci_dev *dev, unsigned int hwirq, unsigned int virq); diff --git a/arch/powerpc/platforms/powernv/opal-wrappers.S b/arch/powerpc/platforms/powernv/opal-wrappers.S index 6f4b00a2ac46..5da790fb7fef 100644 --- a/arch/powerpc/platforms/powernv/opal-wrappers.S +++ b/arch/powerpc/platforms/powernv/opal-wrappers.S @@ -320,3 +320,5 @@ OPAL_CALL(opal_set_powercap, OPAL_SET_POWERCAP); OPAL_CALL(opal_get_power_shift_ratio, OPAL_GET_POWER_SHIFT_RATIO); OPAL_CALL(opal_set_power_shift_ratio, OPAL_SET_POWER_SHIFT_RATIO); OPAL_CALL(opal_sensor_group_clear, OPAL_SENSOR_GROUP_CLEAR); +OPAL_CALL(opal_pci_get_pbcq_tunnel_bar, OPAL_PCI_GET_PBCQ_TUNNEL_BAR); +OPAL_CALL(opal_pci_set_pbcq_tunnel_bar, OPAL_PCI_SET_PBCQ_TUNNEL_BAR); diff --git a/arch/powerpc/platforms/powernv/pci-cxl.c b/arch/powerpc/platforms/powernv/pci-cxl.c index 94498a04558b..cee003de63af 100644 --- a/arch/powerpc/platforms/powernv/pci-cxl.c +++ b/arch/powerpc/platforms/powernv/pci-cxl.c @@ -16,14 +16,6 @@ #include "pci.h" -struct device_node *pnv_pci_get_phb_node(struct pci_dev *dev) -{ - struct pci_controller *hose = pci_bus_to_host(dev->bus); - - return of_node_get(hose->dn); -} -EXPORT_SYMBOL(pnv_pci_get_phb_node); - int pnv_phb_to_cxl_mode(struct pci_dev *dev, uint64_t mode) { struct pci_controller *hose = pci_bus_to_host(dev->bus); diff --git a/arch/powerpc/platforms/powernv/pci.c b/arch/powerpc/platforms/powernv/pci.c index 5422f4a6317c..ac454c6ef08c 100644 --- a/arch/powerpc/platforms/powernv/pci.c +++ b/arch/powerpc/platforms/powernv/pci.c @@ -18,6 +18,7 @@ #include <linux/io.h> #include <linux/msi.h> #include <linux/iommu.h> +#include <linux/sched/mm.h> #include <asm/sections.h> #include <asm/io.h> @@ -38,6 +39,7 @@ #include "pci.h" static DEFINE_MUTEX(p2p_mutex); +static DEFINE_MUTEX(tunnel_mutex); int pnv_pci_get_slot_id(struct device_node *np, uint64_t *id) { @@ -1092,6 +1094,111 @@ int pnv_pci_set_p2p(struct pci_dev *initiator, struct pci_dev *target, u64 desc) } EXPORT_SYMBOL_GPL(pnv_pci_set_p2p); +struct device_node *pnv_pci_get_phb_node(struct pci_dev *dev) +{ + struct pci_controller *hose = pci_bus_to_host(dev->bus); + + return of_node_get(hose->dn); +} +EXPORT_SYMBOL(pnv_pci_get_phb_node); + +int pnv_pci_get_tunnel_ind(struct pci_dev *dev, u64 *asnind) +{ + struct device_node *np; + const __be32 *prop; + + if (!radix_enabled()) + return -ENXIO; + + if (!(np = pnv_pci_get_phb_node(dev))) + return -ENXIO; + + prop = of_get_property(np, "ibm,phb-indications", NULL); + of_node_put(np); + + if (!prop || !prop[1]) + return -ENXIO; + + *asnind = (u64)be32_to_cpu(prop[1]); + return 0; +} +EXPORT_SYMBOL_GPL(pnv_pci_get_tunnel_ind); + +int pnv_pci_set_tunnel_bar(struct pci_dev *dev, u64 addr, int enable) +{ + __be64 val; + struct pci_controller *hose; + struct pnv_phb *phb; + u64 tunnel_bar; + int rc; + + if (!opal_check_token(OPAL_PCI_GET_PBCQ_TUNNEL_BAR)) + return -ENXIO; + if (!opal_check_token(OPAL_PCI_SET_PBCQ_TUNNEL_BAR)) + return -ENXIO; + + hose = pci_bus_to_host(dev->bus); + phb = hose->private_data; + + mutex_lock(&tunnel_mutex); + rc = opal_pci_get_pbcq_tunnel_bar(phb->opal_id, &val); + if (rc != OPAL_SUCCESS) { + rc = -EIO; + goto out; + } + tunnel_bar = be64_to_cpu(val); + if (enable) { + /* + * Only one device per PHB can use atomics. + * Our policy is first-come, first-served. + */ + if (tunnel_bar) { + if (tunnel_bar != addr) + rc = -EBUSY; + goto out; + } + } else { + /* + * The device that owns atomics and wants to release + * them must pass the same address with enable == 0. + */ + if (tunnel_bar != addr) { + rc = -EPERM; + goto out; + } + addr = 0x0ULL; + } + rc = opal_pci_set_pbcq_tunnel_bar(phb->opal_id, addr); + rc = opal_error_code(rc); +out: + mutex_unlock(&tunnel_mutex); + return rc; +} +EXPORT_SYMBOL_GPL(pnv_pci_set_tunnel_bar); + +#ifdef CONFIG_PPC64 /* for thread.tidr */ +int pnv_pci_get_as_notify_info(struct task_struct *task, u32 *lpid, u32 *pid, + u32 *tid) +{ + struct mm_struct *mm = NULL; + + if (task == NULL) + return -EINVAL; + + mm = get_task_mm(task); + if (mm == NULL) + return -EINVAL; + + *pid = mm->context.id; + mmput(mm); + + *tid = task->thread.tidr; + *lpid = mfspr(SPRN_LPID); + return 0; +} +EXPORT_SYMBOL_GPL(pnv_pci_get_as_notify_info); +#endif + void pnv_pci_shutdown(void) { struct pci_controller *hose; -- 2.15.1