commit 6092e8b1fc0c6b7cba4c4d75e66bc9aa9eceab15
author Olaf Baehring <olaf.baehring@draeger.com> Wed May 21 08:03:40 2025 -0300
committer Fabio Estevam <festevam@gmail.com> Thu May 22 09:01:51 2025 -0300
tree 50ecf449a82f80cf3d70cf7d7375407b7aec99bf
parent a22800bc314f370853316d1915699a1c89d1572c

caam: Fix CAAM error on startup

In rare cases U-Boot returns an error message when intantiating the RNG
of the CAAM device:
“SEC0:  RNG4 SH0 instantiation failed with error 0xffffffff”
This  means, that even when the CAAM device reports a finished
descriptor, none is found in the output ring.
This might be caused by a missing cache invalidation before
reading the memory of the output ring
This patch moves the cache invalidation of the output ring from start of
the job to immediately after the notification from hardware where the
output ring will be read.

Signed-off-by: Olaf Baehring <olaf.baehring@draeger.com>
Signed-off-by: Fabio Estevam <festevam@gmail.com>

drivers/crypto/fsl/jr.c

diff --git a/drivers/crypto/fsl/jr.c b/drivers/crypto/fsl/jr.c
index 8f7a821..1d95d2b 100644
--- a/drivers/crypto/fsl/jr.c
+++ b/drivers/crypto/fsl/jr.c
@@ -217,13 +217,6 @@
 
 	jr->head = (head + 1) & (jr->size - 1);
 
-	/* Invalidate output ring */
-	start = (unsigned long)jr->output_ring &
-					~(ARCH_DMA_MINALIGN - 1);
-	end = ALIGN((unsigned long)jr->output_ring + jr->op_size,
-		    ARCH_DMA_MINALIGN);
-	invalidate_dcache_range(start, end);
-
 	sec_out32(&regs->irja, 1);
 
 	return 0;
@@ -243,6 +236,7 @@
 #else
 	uint32_t *addr;
 #endif
+	unsigned long start, end;
 
 	while (sec_in32(&regs->orsf) && CIRC_CNT(jr->head, jr->tail,
 						 jr->size)) {
@@ -250,6 +244,11 @@
 		found = 0;
 
 		caam_dma_addr_t op_desc;
+
+		/* Invalidate output ring */
+		start = (unsigned long)jr->output_ring & ~(ARCH_DMA_MINALIGN - 1);
+		end = ALIGN((unsigned long)jr->output_ring + jr->op_size, ARCH_DMA_MINALIGN);
+		invalidate_dcache_range(start, end);
 	#ifdef CONFIG_CAAM_64BIT
 		/* Read the 64 bit Descriptor address from Output Ring.
 		 * The 32 bit hign and low part of the address will
@@ -283,8 +282,13 @@
 		}
 
 		/* Error condition if match not found */
-		if (!found)
+		if (!found) {
+			int slots_full = sec_in32(&regs->orsf);
+
+			jr->tail = (jr->tail + slots_full) & (jr->size - 1);
+			sec_out32(&regs->orjr, slots_full);
 			return -1;
+		}
 
 		jr->info[idx].op_done = 1;
 		callback = (void *)jr->info[idx].callback;
@@ -296,14 +300,14 @@
 		 */
 		if (idx == tail)
 			do {
+				jr->info[tail].op_done = 0;
 				tail = (tail + 1) & (jr->size - 1);
 			} while (jr->info[tail].op_done);
 
 		jr->tail = tail;
-		jr->read_idx = (jr->read_idx + 1) & (jr->size - 1);
+
 
 		sec_out32(&regs->orjr, 1);
-		jr->info[idx].op_done = 0;
 
 		callback(status, arg);
 	}
@@ -378,7 +382,6 @@
 
 	jr->head = 0;
 	jr->tail = 0;
-	jr->read_idx = 0;
 	jr->write_idx = 0;
 	memset(jr->info, 0, sizeof(jr->info));
 	memset(jr->input_ring, 0, jr->size * sizeof(caam_dma_addr_t));