Define an interface to open a VAS send window. This interface is
intended to be used the Nest Accelerator (NX) driver(s) to open
a send window and use it to submit compression/encryption requests
to a VAS receive window.
The receive window, identified by the [vasid, cop] parameters, must
already be open in VAS (i.e connected to an NX engine).
Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
---
Changelog[v6]:
- Add support for FTW windows
Changelog[v4]:
- [Ben Herrenschmidt] MMIO regions must be mapped non-cached and
paste regions must be mapped cached. Define/use map_paste_region().
Changelog [v3]:
- Distinguish between hardware PID (SPRN_PID) and Linux pid.
- Use macros rather than enum for threshold-control mode
- Set the pid of send window from attr (needed for user space
send windows).
- Ignore irq port setting for now. They are needed for user space
windows and will be added later
---
arch/powerpc/include/asm/vas.h | 42 ++++++++
arch/powerpc/platforms/powernv/vas-window.c | 157 +++++++++++++++++++++++++++-
2 files changed, 196 insertions(+), 3 deletions(-)
diff --git a/arch/powerpc/include/asm/vas.h b/arch/powerpc/include/asm/vas.h
index e1c5376..3fc6435 100644
--- a/arch/powerpc/include/asm/vas.h
+++ b/arch/powerpc/include/asm/vas.h
@@ -65,6 +65,29 @@ struct vas_rx_win_attr {
};
/*
+ * Window attributes specified by the in-kernel owner of a send window.
+ */
+struct vas_tx_win_attr {
+ enum vas_cop_type cop;
+ int wcreds_max;
+ int lpid;
+ int pidr; /* hardware PID (from SPRN_PID) */
+ int pid; /* linux process id */
+ int pswid;
+ int rsvd_txbuf_count;
+ int tc_mode;
+
+ bool user_win;
+ bool pin_win;
+ bool rej_no_credit;
+ bool rsvd_txbuf_enable;
+ bool tx_wcred_mode;
+ bool rx_wcred_mode;
+ bool tx_win_ord_mode;
+ bool rx_win_ord_mode;
+};
+
+/*
* Return a system-wide unique id for the VAS window @win.
*/
extern uint32_t vas_win_id(struct vas_window *win);
@@ -92,6 +115,25 @@ extern struct vas_window *vas_rx_win_open(int vasid, enum
vas_cop_type cop,
struct vas_rx_win_attr *attr);
/*
+ * Helper to initialize send window attributes to defaults for an NX window.
+ */
+extern void vas_init_tx_win_attr(struct vas_tx_win_attr *txattr,
+ enum vas_cop_type cop);
+
+/*
+ * Open a VAS send window for the instance of VAS identified by @vasid
+ * and the co-processor type @cop. Use @attr to initialize attributes
+ * of the window.
+ *
+ * Note: The instance of VAS must already have an open receive window for
+ * the coprocessor type @cop.
+ *
+ * Return a handle to the send window or ERR_PTR() on error.
+ */
+struct vas_window *vas_tx_win_open(int vasid, enum vas_cop_type cop,
+ struct vas_tx_win_attr *attr);
+
+/*
* Close the send or receive window identified by @win. For receive windows
* return -EAGAIN if there are active send windows attached to this receive
* window.
diff --git a/arch/powerpc/platforms/powernv/vas-window.c
b/arch/powerpc/platforms/powernv/vas-window.c
index 9704a3b..3e2655c 100644
--- a/arch/powerpc/platforms/powernv/vas-window.c
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -72,7 +72,7 @@ static inline void get_uwc_mmio_bar(struct vas_window *window,
* space. Unlike MMIO regions (map_mmio_region() below), paste region must
* be mapped cache-able and is only applicable to send windows.
*/
-void *map_paste_region(struct vas_window *txwin)
+static void *map_paste_region(struct vas_window *txwin)
{
int rc, len;
void *map;
@@ -109,7 +109,6 @@ void *map_paste_region(struct vas_window *txwin)
return ERR_PTR(rc);
}
-
static void *map_mmio_region(char *name, uint64_t start, int len)
{
void *map;
@@ -657,7 +656,7 @@ struct vas_window *get_user_rxwin(struct vas_instance
*vinst, uint32_t pswid)
*
* See also function header of set_vinst_win().
*/
-struct vas_window *get_vinst_rxwin(struct vas_instance *vinst,
+static struct vas_window *get_vinst_rxwin(struct vas_instance *vinst,
enum vas_cop_type cop, uint32_t pswid)
{
struct vas_window *rxwin;
@@ -933,6 +932,158 @@ struct vas_window *vas_rx_win_open(int vasid, enum
vas_cop_type cop,
}
EXPORT_SYMBOL_GPL(vas_rx_win_open);
+void vas_init_tx_win_attr(struct vas_tx_win_attr *txattr, enum vas_cop_type
cop)
+{
+ memset(txattr, 0, sizeof(*txattr));
+
+ if (cop == VAS_COP_TYPE_842 || cop == VAS_COP_TYPE_842_HIPRI) {
+ txattr->rej_no_credit = false;
+ txattr->rx_wcred_mode = true;
+ txattr->tx_wcred_mode = true;
+ txattr->rx_win_ord_mode = true;
+ txattr->tx_win_ord_mode = true;
+ }
+}
+EXPORT_SYMBOL_GPL(vas_init_tx_win_attr);
+
+static void init_winctx_for_txwin(struct vas_window *txwin,
+ struct vas_tx_win_attr *txattr,
+ struct vas_winctx *winctx)
+{
+ /*
+ * We first zero all fields and only set non-zero ones. Following
+ * are some fields set to 0/false for the stated reason:
+ *
+ * ->notify_os_intr_reg In powerNV, send intrs to HV
+ * ->rsvd_txbuf_count Not supported yet.
+ * ->notify_disable False for NX windows
+ * ->xtra_write False for NX windows
+ * ->notify_early NA for NX windows
+ * ->lnotify_lpid NA for Tx windows
+ * ->lnotify_pid NA for Tx windows
+ * ->lnotify_tid NA for Tx windows
+ * ->tx_win_cred_mode Ignore for now for NX windows
+ * ->rx_win_cred_mode Ignore for now for NX windows
+ */
+ memset(winctx, 0, sizeof(struct vas_winctx));
+
+ winctx->wcreds_max = txattr->wcreds_max ?: VAS_WCREDS_DEFAULT;
+
+ winctx->user_win = txattr->user_win;
+ winctx->nx_win = txwin->rxwin->nx_win;
+ winctx->pin_win = txattr->pin_win;
+
+ winctx->rx_wcred_mode = txattr->rx_wcred_mode;
+ winctx->tx_wcred_mode = txattr->tx_wcred_mode;
+ winctx->rx_word_mode = txattr->rx_win_ord_mode;
+ winctx->tx_word_mode = txattr->tx_win_ord_mode;
+
+ if (winctx->nx_win) {
+ winctx->data_stamp = true;
+ winctx->intr_disable = true;
+ }
+
+ winctx->lpid = txattr->lpid;
+ winctx->pidr = txattr->pidr;
+ winctx->rx_win_id = txwin->rxwin->winid;
+
+ winctx->dma_type = VAS_DMA_TYPE_INJECT;
+ winctx->tc_mode = txattr->tc_mode;
+ winctx->min_scope = VAS_SCOPE_LOCAL;
+ winctx->max_scope = VAS_SCOPE_VECTORED_GROUP;
+
+ winctx->pswid = encode_pswid(txwin->vinst->vas_id, txwin->winid);
+}
+
+static bool tx_win_args_valid(enum vas_cop_type cop,
+ struct vas_tx_win_attr *attr)
+{
+ if (attr->tc_mode != VAS_THRESH_DISABLED)
+ return false;
+
+ if (cop > VAS_COP_TYPE_MAX)
+ return false;
+
+ if (attr->user_win &&
+ (cop != VAS_COP_TYPE_FTW || attr->rsvd_txbuf_count))
+ return false;
+
+ return true;
+}
+
+struct vas_window *vas_tx_win_open(int vasid, enum vas_cop_type cop,
+ struct vas_tx_win_attr *attr)
+{
+ int rc;
+ struct vas_instance *vinst;
+ struct vas_window *txwin;
+ struct vas_window *rxwin;
+ struct vas_winctx winctx;
+
+ if (!vas_initialized())
+ return ERR_PTR(-EAGAIN);
+
+ if (!tx_win_args_valid(cop, attr))
+ return ERR_PTR(-EINVAL);
+
+ vinst = find_vas_instance(vasid);
+ if (!vinst) {
+ pr_devel("VAS: vasid %d not found!\n", vasid);
+ return ERR_PTR(-EINVAL);
+ }
+
+ rxwin = get_vinst_rxwin(vinst, cop, attr->pswid);
+ if (IS_ERR(rxwin)) {
+ pr_devel("VAS: No RxWin for vasid %d, cop %d\n", vasid, cop);
+ return rxwin;
+ }
+
+ txwin = vas_window_alloc(vinst);
+ if (IS_ERR(txwin)) {
+ rc = PTR_ERR(txwin);
+ goto put_rxwin;
+ }
+
+ txwin->tx_win = 1;
+ txwin->rxwin = rxwin;
+ txwin->nx_win = txwin->rxwin->nx_win;
+ txwin->pid = attr->pid;
+ txwin->user_win = attr->user_win;
+
+ init_winctx_for_txwin(txwin, attr, &winctx);
+
+ init_winctx_regs(txwin, &winctx);
+
+ /*
+ * If its a kernel send window, map the window address into the
+ * kernel's address space. For user windows, user must issue an
+ * mmap() to map the window into their address space.
+ *
+ * NOTE: If kernel ever resubmits a user CRB after handling a page
+ * fault, we will need to map this into kernel as well.
+ */
+ if (!txwin->user_win) {
+ txwin->paste_kaddr = map_paste_region(txwin);
+ if (IS_ERR(txwin->paste_kaddr)) {
+ rc = PTR_ERR(txwin->paste_kaddr);
+ goto free_window;
+ }
+ }
+
+ set_vinst_win(vinst, txwin);
+
+ return txwin;
+
+free_window:
+ vas_window_free(txwin);
+
+put_rxwin:
+ put_rx_win(rxwin);
+ return ERR_PTR(rc);
+
+}
+EXPORT_SYMBOL_GPL(vas_tx_win_open);
+
static void poll_window_busy_state(struct vas_window *window)
{
int busy;
--
2.7.4
