mailbox: bcm-pdc: Changes so mbox client can be removed / re-inserted
Ensure that DMA is disabled, and pointers reset, when changing
DMA base addresses in pdc_ring_init(). This allows a mailbox client
to be re-inserted after being removed. Otherwise, the DMA doesn't
restart so the client hangs while being reinserted.
Signed-off-by: Steve Lin <steven.lin1@broadcom.com>
Signed-off-by: Rob Rice <rob.rice@broadcom.com>
Reviewed-by: Andy Gospodarek <gospo@broadcom.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>
diff --git a/drivers/mailbox/bcm-pdc-mailbox.c b/drivers/mailbox/bcm-pdc-mailbox.c
index a9c804f..3b4ebbe 100644
--- a/drivers/mailbox/bcm-pdc-mailbox.c
+++ b/drivers/mailbox/bcm-pdc-mailbox.c
@@ -117,15 +117,16 @@
/*
* Sets the following bits for write to transmit control reg:
- * 0 - XmtEn - enable activity on the tx channel
* 11 - PtyChkDisable - parity check is disabled
* 20:18 - BurstLen = 3 -> 2^7 = 128 byte data reads from memory
*/
-#define PDC_TX_CTL 0x000C0801
+#define PDC_TX_CTL 0x000C0800
+
+/* Bit in tx control reg to enable tx channel */
+#define PDC_TX_ENABLE 0x1
/*
* Sets the following bits for write to receive control reg:
- * 0 - RcvEn - enable activity on the rx channel
* 7:1 - RcvOffset - size in bytes of status region at start of rx frame buf
* 9 - SepRxHdrDescEn - place start of new frames only in descriptors
* that have StartOfFrame set
@@ -135,7 +136,10 @@
* 11 - PtyChkDisable - parity check is disabled
* 20:18 - BurstLen = 3 -> 2^7 = 128 byte data reads from memory
*/
-#define PDC_RX_CTL 0x000C0E01
+#define PDC_RX_CTL 0x000C0E00
+
+/* Bit in rx control reg to enable rx channel */
+#define PDC_RX_ENABLE 0x1
#define CRYPTO_D64_RS0_CD_MASK ((PDC_RING_ENTRIES * RING_ENTRY_SIZE) - 1)
@@ -1054,6 +1058,15 @@
/* Tell device the base DMA address of each ring */
dma_reg = &pdcs->regs->dmaregs[ringset];
+
+ /* But first disable DMA and set curptr to 0 for both TX & RX */
+ iowrite32(PDC_TX_CTL, &dma_reg->dmaxmt.control);
+ iowrite32((PDC_RX_CTL + (pdcs->rx_status_len << 1)),
+ (void *)&dma_reg->dmarcv.control);
+ iowrite32(0, (void *)&dma_reg->dmaxmt.ptr);
+ iowrite32(0, (void *)&dma_reg->dmarcv.ptr);
+
+ /* Set base DMA addresses */
iowrite32(lower_32_bits(pdcs->tx_ring_alloc.dmabase),
(void *)&dma_reg->dmaxmt.addrlow);
iowrite32(upper_32_bits(pdcs->tx_ring_alloc.dmabase),
@@ -1064,6 +1077,11 @@
iowrite32(upper_32_bits(pdcs->rx_ring_alloc.dmabase),
(void *)&dma_reg->dmarcv.addrhigh);
+ /* Re-enable DMA */
+ iowrite32(PDC_TX_CTL | PDC_TX_ENABLE, &dma_reg->dmaxmt.control);
+ iowrite32((PDC_RX_CTL | PDC_RX_ENABLE | (pdcs->rx_status_len << 1)),
+ (void *)&dma_reg->dmarcv.control);
+
/* Initialize descriptors */
for (i = 0; i < PDC_RING_ENTRIES; i++) {
/* Every tx descriptor can be used for start of frame. */
@@ -1235,23 +1253,41 @@
pdcs->nrxd = PDC_RING_ENTRIES;
pdcs->ntxpost = PDC_RING_ENTRIES - 1;
pdcs->nrxpost = PDC_RING_ENTRIES - 1;
- pdcs->regs->intmask = 0;
+ iowrite32(0, &pdcs->regs->intmask);
dma_reg = &pdcs->regs->dmaregs[ringset];
- iowrite32(0, (void *)&dma_reg->dmaxmt.ptr);
- iowrite32(0, (void *)&dma_reg->dmarcv.ptr);
- iowrite32(PDC_TX_CTL, (void *)&dma_reg->dmaxmt.control);
+ /* Configure DMA but will enable later in pdc_ring_init() */
+ iowrite32(PDC_TX_CTL, &dma_reg->dmaxmt.control);
iowrite32(PDC_RX_CTL + (pdcs->rx_status_len << 1),
(void *)&dma_reg->dmarcv.control);
+ /* Reset current index pointers after making sure DMA is disabled */
+ iowrite32(0, &dma_reg->dmaxmt.ptr);
+ iowrite32(0, &dma_reg->dmarcv.ptr);
+
if (pdcs->pdc_resp_hdr_len == PDC_SPU2_RESP_HDR_LEN)
iowrite32(PDC_CKSUM_CTRL,
pdcs->pdc_reg_vbase + PDC_CKSUM_CTRL_OFFSET);
}
/**
+ * pdc_hw_disable() - Disable the tx and rx control in the hw.
+ * @pdcs: PDC state structure
+ *
+ */
+static void pdc_hw_disable(struct pdc_state *pdcs)
+{
+ struct dma64 *dma_reg;
+
+ dma_reg = &pdcs->regs->dmaregs[PDC_RINGSET];
+ iowrite32(PDC_TX_CTL, &dma_reg->dmaxmt.control);
+ iowrite32(PDC_RX_CTL + (pdcs->rx_status_len << 1),
+ &dma_reg->dmarcv.control);
+}
+
+/**
* pdc_rx_buf_pool_create() - Pool of receive buffers used to catch the metadata
* header returned with each response message.
* @pdcs: PDC state structure
@@ -1505,6 +1541,8 @@
pdc_free_debugfs();
+ pdc_hw_disable(pdcs);
+
mbox_controller_unregister(&pdcs->mbc);
dma_pool_destroy(pdcs->rx_buf_pool);