diff options
| -rw-r--r-- | arch/powerpc/include/asm/vas.h | 45 | ||||
| -rw-r--r-- | arch/powerpc/platforms/powernv/vas-window.c | 283 | ||||
| -rw-r--r-- | arch/powerpc/platforms/powernv/vas.h | 14 |
3 files changed, 341 insertions, 1 deletions
diff --git a/arch/powerpc/include/asm/vas.h b/arch/powerpc/include/asm/vas.h index 7dcf3bded343..18c59c3ade3d 100644 --- a/arch/powerpc/include/asm/vas.h +++ b/arch/powerpc/include/asm/vas.h @@ -50,4 +50,49 @@ enum vas_cop_type { VAS_COP_TYPE_MAX, }; +/* + * Receive window attributes specified by the (in-kernel) owner of window. + */ +struct vas_rx_win_attr { + void *rx_fifo; + int rx_fifo_size; + int wcreds_max; + + bool pin_win; + bool rej_no_credit; + bool tx_wcred_mode; + bool rx_wcred_mode; + bool tx_win_ord_mode; + bool rx_win_ord_mode; + bool data_stamp; + bool nx_win; + bool fault_win; + bool user_win; + bool notify_disable; + bool intr_disable; + bool notify_early; + + int lnotify_lpid; + int lnotify_pid; + int lnotify_tid; + u32 pswid; + + int tc_mode; +}; + +/* + * Helper to initialize receive window attributes to defaults for an + * NX window. + */ +void vas_init_rx_win_attr(struct vas_rx_win_attr *rxattr, enum vas_cop_type cop); + +/* + * Open a VAS receive window for the instance of VAS identified by @vasid + * Use @attr to initialize the attributes of the window. + * + * Return a handle to the window or ERR_PTR() on error. + */ +struct vas_window *vas_rx_win_open(int vasid, enum vas_cop_type cop, + struct vas_rx_win_attr *attr); + #endif /* __ASM_POWERPC_VAS_H */ diff --git a/arch/powerpc/platforms/powernv/vas-window.c b/arch/powerpc/platforms/powernv/vas-window.c index bfc9dba24b65..783c8c6585d4 100644 --- a/arch/powerpc/platforms/powernv/vas-window.c +++ b/arch/powerpc/platforms/powernv/vas-window.c @@ -14,6 +14,8 @@ #include <linux/slab.h> #include <linux/io.h> #include <linux/log2.h> +#include <linux/rcupdate.h> +#include <linux/cred.h> #include "vas.h" @@ -531,7 +533,7 @@ void vas_window_free(struct vas_window *window) vas_release_window_id(&vinst->ida, winid); } -struct vas_window *vas_window_alloc(struct vas_instance *vinst) +static struct vas_window *vas_window_alloc(struct vas_instance *vinst) { int winid; struct vas_window *window; @@ -558,6 +560,285 @@ out_free: return ERR_PTR(-ENOMEM); } +/* + * Get the VAS receive window associated with NX engine identified + * by @cop and if applicable, @pswid. + * + * See also function header of set_vinst_win(). + */ +struct vas_window *get_vinst_rxwin(struct vas_instance *vinst, + enum vas_cop_type cop, u32 pswid) +{ + struct vas_window *rxwin; + + mutex_lock(&vinst->mutex); + + if (cop == VAS_COP_TYPE_842 || cop == VAS_COP_TYPE_842_HIPRI) + rxwin = vinst->rxwin[cop] ?: ERR_PTR(-EINVAL); + else + rxwin = ERR_PTR(-EINVAL); + + if (!IS_ERR(rxwin)) + atomic_inc(&rxwin->num_txwins); + + mutex_unlock(&vinst->mutex); + + return rxwin; +} + +/* + * We have two tables of windows in a VAS instance. The first one, + * ->windows[], contains all the windows in the instance and allows + * looking up a window by its id. It is used to look up send windows + * during fault handling and receive windows when pairing user space + * send/receive windows. + * + * The second table, ->rxwin[], contains receive windows that are + * associated with NX engines. This table has VAS_COP_TYPE_MAX + * entries and is used to look up a receive window by its + * coprocessor type. + * + * Here, we save @window in the ->windows[] table. If it is a receive + * window, we also save the window in the ->rxwin[] table. + */ +static void set_vinst_win(struct vas_instance *vinst, + struct vas_window *window) +{ + int id = window->winid; + + mutex_lock(&vinst->mutex); + + /* + * There should only be one receive window for a coprocessor type + * unless its a user (FTW) window. + */ + if (!window->user_win && !window->tx_win) { + WARN_ON_ONCE(vinst->rxwin[window->cop]); + vinst->rxwin[window->cop] = window; + } + + WARN_ON_ONCE(vinst->windows[id] != NULL); + vinst->windows[id] = window; + + mutex_unlock(&vinst->mutex); +} + +/* + * Clear this window from the table(s) of windows for this VAS instance. + * See also function header of set_vinst_win(). + */ +void clear_vinst_win(struct vas_window *window) +{ + int id = window->winid; + struct vas_instance *vinst = window->vinst; + + mutex_lock(&vinst->mutex); + + if (!window->user_win && !window->tx_win) { + WARN_ON_ONCE(!vinst->rxwin[window->cop]); + vinst->rxwin[window->cop] = NULL; + } + + WARN_ON_ONCE(vinst->windows[id] != window); + vinst->windows[id] = NULL; + + mutex_unlock(&vinst->mutex); +} + +static void init_winctx_for_rxwin(struct vas_window *rxwin, + struct vas_rx_win_attr *rxattr, + struct vas_winctx *winctx) +{ + /* + * We first zero (memset()) all fields and only set non-zero fields. + * Following fields are 0/false but maybe deserve a comment: + * + * ->notify_os_intr_reg In powerNV, send intrs to HV + * ->notify_disable False for NX windows + * ->intr_disable False for Fault Windows + * ->xtra_write False for NX windows + * ->notify_early NA for NX windows + * ->rsvd_txbuf_count NA for Rx windows + * ->lpid, ->pid, ->tid NA for Rx windows + */ + + memset(winctx, 0, sizeof(struct vas_winctx)); + + winctx->rx_fifo = rxattr->rx_fifo; + winctx->rx_fifo_size = rxattr->rx_fifo_size; + winctx->wcreds_max = rxattr->wcreds_max ?: VAS_WCREDS_DEFAULT; + winctx->pin_win = rxattr->pin_win; + + winctx->nx_win = rxattr->nx_win; + winctx->fault_win = rxattr->fault_win; + winctx->rx_word_mode = rxattr->rx_win_ord_mode; + winctx->tx_word_mode = rxattr->tx_win_ord_mode; + winctx->rx_wcred_mode = rxattr->rx_wcred_mode; + winctx->tx_wcred_mode = rxattr->tx_wcred_mode; + + if (winctx->nx_win) { + winctx->data_stamp = true; + winctx->intr_disable = true; + winctx->pin_win = true; + + WARN_ON_ONCE(winctx->fault_win); + WARN_ON_ONCE(!winctx->rx_word_mode); + WARN_ON_ONCE(!winctx->tx_word_mode); + WARN_ON_ONCE(winctx->notify_after_count); + } else if (winctx->fault_win) { + winctx->notify_disable = true; + } else if (winctx->user_win) { + /* + * Section 1.8.1 Low Latency Core-Core Wake up of + * the VAS workbook: + * + * - disable credit checks ([tr]x_wcred_mode = false) + * - disable FIFO writes + * - enable ASB_Notify, disable interrupt + */ + winctx->fifo_disable = true; + winctx->intr_disable = true; + winctx->rx_fifo = NULL; + } + + winctx->lnotify_lpid = rxattr->lnotify_lpid; + winctx->lnotify_pid = rxattr->lnotify_pid; + winctx->lnotify_tid = rxattr->lnotify_tid; + winctx->pswid = rxattr->pswid; + winctx->dma_type = VAS_DMA_TYPE_INJECT; + winctx->tc_mode = rxattr->tc_mode; + + winctx->min_scope = VAS_SCOPE_LOCAL; + winctx->max_scope = VAS_SCOPE_VECTORED_GROUP; +} + +static bool rx_win_args_valid(enum vas_cop_type cop, + struct vas_rx_win_attr *attr) +{ + dump_rx_win_attr(attr); + + if (cop >= VAS_COP_TYPE_MAX) + return false; + + if (cop != VAS_COP_TYPE_FTW && + attr->rx_fifo_size < VAS_RX_FIFO_SIZE_MIN) + return false; + + if (attr->rx_fifo_size > VAS_RX_FIFO_SIZE_MAX) + return false; + + if (attr->nx_win) { + /* cannot be fault or user window if it is nx */ + if (attr->fault_win || attr->user_win) + return false; + /* + * Section 3.1.4.32: NX Windows must not disable notification, + * and must not enable interrupts or early notification. + */ + if (attr->notify_disable || !attr->intr_disable || + attr->notify_early) + return false; + } else if (attr->fault_win) { + /* cannot be both fault and user window */ + if (attr->user_win) + return false; + + /* + * Section 3.1.4.32: Fault windows must disable notification + * but not interrupts. + */ + if (!attr->notify_disable || attr->intr_disable) + return false; + + } else if (attr->user_win) { + /* + * User receive windows are only for fast-thread-wakeup + * (FTW). They don't need a FIFO and must disable interrupts + */ + if (attr->rx_fifo || attr->rx_fifo_size || !attr->intr_disable) + return false; + } else { + /* Rx window must be one of NX or Fault or User window. */ + return false; + } + + return true; +} + +void vas_init_rx_win_attr(struct vas_rx_win_attr *rxattr, enum vas_cop_type cop) +{ + memset(rxattr, 0, sizeof(*rxattr)); + + if (cop == VAS_COP_TYPE_842 || cop == VAS_COP_TYPE_842_HIPRI) { + rxattr->pin_win = true; + rxattr->nx_win = true; + rxattr->fault_win = false; + rxattr->intr_disable = true; + rxattr->rx_wcred_mode = true; + rxattr->tx_wcred_mode = true; + rxattr->rx_win_ord_mode = true; + rxattr->tx_win_ord_mode = true; + } else if (cop == VAS_COP_TYPE_FAULT) { + rxattr->pin_win = true; + rxattr->fault_win = true; + rxattr->notify_disable = true; + rxattr->rx_wcred_mode = true; + rxattr->tx_wcred_mode = true; + rxattr->rx_win_ord_mode = true; + rxattr->tx_win_ord_mode = true; + } else if (cop == VAS_COP_TYPE_FTW) { + rxattr->user_win = true; + rxattr->intr_disable = true; + + /* + * As noted in the VAS Workbook we disable credit checks. + * If we enable credit checks in the future, we must also + * implement a mechanism to return the user credits or new + * paste operations will fail. + */ + } +} +EXPORT_SYMBOL_GPL(vas_init_rx_win_attr); + +struct vas_window *vas_rx_win_open(int vasid, enum vas_cop_type cop, + struct vas_rx_win_attr *rxattr) +{ + struct vas_window *rxwin; + struct vas_winctx winctx; + struct vas_instance *vinst; + + if (!rx_win_args_valid(cop, rxattr)) + return ERR_PTR(-EINVAL); + + vinst = find_vas_instance(vasid); + if (!vinst) { + pr_devel("vasid %d not found!\n", vasid); + return ERR_PTR(-EINVAL); + } + pr_devel("Found instance %d\n", vasid); + + rxwin = vas_window_alloc(vinst); + if (IS_ERR(rxwin)) { + pr_devel("Unable to allocate memory for Rx window\n"); + return rxwin; + } + + rxwin->tx_win = false; + rxwin->nx_win = rxattr->nx_win; + rxwin->user_win = rxattr->user_win; + rxwin->cop = cop; + if (rxattr->user_win) + rxwin->pid = task_pid_vnr(current); + + init_winctx_for_rxwin(rxwin, rxattr, &winctx); + init_winctx_regs(rxwin, &winctx); + + set_vinst_win(vinst, rxwin); + + return rxwin; +} +EXPORT_SYMBOL_GPL(vas_rx_win_open); + /* stub for now */ int vas_win_close(struct vas_window *window) { diff --git a/arch/powerpc/platforms/powernv/vas.h b/arch/powerpc/platforms/powernv/vas.h index 60a3c3c1615b..d3e4f554a11c 100644 --- a/arch/powerpc/platforms/powernv/vas.h +++ b/arch/powerpc/platforms/powernv/vas.h @@ -289,6 +289,9 @@ enum vas_notify_after_count { /* * One per instance of VAS. Each instance will have a separate set of * receive windows, one per coprocessor type. + * + * See also function header of set_vinst_win() for details on ->windows[] + * and ->rxwin[] tables. */ struct vas_instance { int vas_id; @@ -393,6 +396,16 @@ extern struct vas_instance *find_vas_instance(int vasid); #define VREG(r) VREG_SFX(r, _OFFSET) #ifdef vas_debug +static inline void dump_rx_win_attr(struct vas_rx_win_attr *attr) +{ + pr_err("VAS: fault %d, notify %d, intr %d early %d\n", + attr->fault_win, attr->notify_disable, + attr->intr_disable, attr->notify_early); + + pr_err("VAS: rx_fifo_size %d, max value %d\n", + attr->rx_fifo_size, VAS_RX_FIFO_SIZE_MAX); +} + static inline void vas_log_write(struct vas_window *win, char *name, void *regptr, u64 val) { @@ -405,6 +418,7 @@ static inline void vas_log_write(struct vas_window *win, char *name, #else /* vas_debug */ #define vas_log_write(win, name, reg, val) +#define dump_rx_win_attr(attr) #endif /* vas_debug */ |