[Skiboot] [PATCH 04/11] xive/p9: Introduce XIVE_EQ_ORDER

[Cédric Le Goater]

XIVE_EQ_ORDER defines the number of EQ descriptors per chip the system
can use.

The EQ descriptors can be controlled by ESB pages also and the driver
defines in the VC BAR of the controller a range of 128G of ESB pages
giving access to 1M EQs. All ESB pages are backed by a memory table,
so we are fine but we could improve the configuration.

Signed-off-by: Cédric Le Goater <clg at kaod.org>
---
 hw/xive.c | 17 +++++++++--------
 1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/hw/xive.c b/hw/xive.c
index 9b4ed66f7194..2a132ce87f3b 100644
--- a/hw/xive.c
+++ b/hw/xive.c
@@ -173,11 +173,12 @@
  * 2K EQs. We need 512 pointers, ie, 4K of memory for the indirect
  * table.
  *
- * XXX Adjust that based on BAR value ?
+ * TODO: adjust the VC BAR range for END ESBs on this value
  */
-#define MAX_EQ_COUNT		(1 * 1024 * 1024)
+#define XIVE_EQ_ORDER		20 /* 1M ENDs */
+#define XIVE_EQ_COUNT		(1ul << XIVE_EQ_ORDER)
 #define EQ_PER_PAGE		(0x10000 / 32) // Use sizeof ?
-#define IND_EQ_TABLE_SIZE	((MAX_EQ_COUNT / EQ_PER_PAGE) * 8)
+#define IND_EQ_TABLE_SIZE	((XIVE_EQ_COUNT / EQ_PER_PAGE) * 8)
 
 /* Number of priorities (and thus EQDs) we allocate for each VP */
 #define NUM_INT_PRIORITIES	8
@@ -389,7 +390,7 @@ struct xive {
 	 * for our basic setup using 64K pages.
 	 *
 	 * The size of the indirect tables are driven by MAX_VP_COUNT and
-	 * MAX_EQ_COUNT. The number of pre-allocated ones are driven by
+	 * XIVE_EQ_COUNT. The number of pre-allocated ones are driven by
 	 * INITIAL_VP_COUNT (number of EQ depends on number of VP) in block
 	 * mode, otherwise we only preallocate INITIAL_BLK0_VP_COUNT on
 	 * block 0.
@@ -865,7 +866,7 @@ static uint32_t xive_alloc_eq_set(struct xive *x, bool alloc_indirect)
 	assert(x->eq_map);
 
 	/* Allocate from the EQ bitmap. Each bit is 8 EQs */
-	idx = bitmap_find_zero_bit(*x->eq_map, 0, MAX_EQ_COUNT >> 3);
+	idx = bitmap_find_zero_bit(*x->eq_map, 0, XIVE_EQ_COUNT >> 3);
 	if (idx < 0) {
 		xive_dbg(x, "Allocation from EQ bitmap failed !\n");
 		return XIVE_ALLOC_NO_SPACE;
@@ -2617,7 +2618,7 @@ static struct xive *init_one_xive(struct dt_node *np)
 		x->int_ipi_top = XIVE_INT_FIRST;
 
 	/* Allocate a few bitmaps */
-	x->eq_map = zalloc(BITMAP_BYTES(MAX_EQ_COUNT >> 3));
+	x->eq_map = zalloc(BITMAP_BYTES(XIVE_EQ_COUNT >> 3));
 	assert(x->eq_map);
 	/* Make sure we don't hand out 0 */
 	bitmap_set_bit(*x->eq_map, 0);
@@ -2666,7 +2667,7 @@ static struct xive *init_one_xive(struct dt_node *np)
 	/* Register escalation sources */
 	__xive_register_source(x, &x->esc_irqs,
 			       MAKE_ESCALATION_GIRQ(x->block_id, 0),
-			       MAX_EQ_COUNT, EQ_ESB_SHIFT,
+			       XIVE_EQ_COUNT, EQ_ESB_SHIFT,
 			       x->eq_mmio, XIVE_SRC_EOI_PAGE1,
 			       false, NULL, NULL);
 
@@ -4421,7 +4422,7 @@ static void xive_reset_one(struct xive *x)
 	xive_dbg(x, "Resetting EQs...\n");
 
 	/* Reset all allocated EQs and free the user ones */
-	bitmap_for_each_one(*x->eq_map, MAX_EQ_COUNT >> 3, i) {
+	bitmap_for_each_one(*x->eq_map, XIVE_EQ_COUNT >> 3, i) {
 		struct xive_eq eq0;
 		struct xive_eq *eq;
 		int j;
-- 
2.25.4