From e004c7e7d3b873a671fecf04f197982806e380eb Mon Sep 17 00:00:00 2001 From: Rob Rice Date: Mon, 14 Nov 2016 13:25:59 -0500 Subject: mailbox: bcm-pdc: streamline rx code Remove the unnecessary rmb() from the receive path. If the rx ring has multiple messages ready, avoid reading last_rx_curr multiple times from the register. Signed-off-by: Rob Rice Reviewed-by: Andy Gospodarek Signed-off-by: Jassi Brar --- drivers/mailbox/bcm-pdc-mailbox.c | 108 +++++++++++++++++--------------------- 1 file changed, 48 insertions(+), 60 deletions(-) (limited to 'drivers/mailbox') diff --git a/drivers/mailbox/bcm-pdc-mailbox.c b/drivers/mailbox/bcm-pdc-mailbox.c index fa3f484d3771..21957609ea91 100644 --- a/drivers/mailbox/bcm-pdc-mailbox.c +++ b/drivers/mailbox/bcm-pdc-mailbox.c @@ -570,27 +570,23 @@ pdc_build_txd(struct pdc_state *pdcs, dma_addr_t dma_addr, u32 buf_len, } /** - * pdc_receive() - Receive a response message from a given SPU. + * pdc_receive_one() - Receive a response message from a given SPU. * @pdcs: PDC state for the SPU to receive from - * @mssg: mailbox message to be returned to client * * When the return code indicates success, the response message is available in * the receive buffers provided prior to submission of the request. * - * Input: - * pdcs - PDC state structure for the SPU to be polled - * mssg - mailbox message to be returned to client. This function sets the - * context pointer on the message to help the client associate the - * response with a request. - * * Return: PDC_SUCCESS if one or more receive descriptors was processed * -EAGAIN indicates that no response message is available * -EIO an error occurred */ static int -pdc_receive(struct pdc_state *pdcs, struct brcm_message *mssg) +pdc_receive_one(struct pdc_state *pdcs) { struct device *dev = &pdcs->pdev->dev; + struct mbox_controller *mbc; + struct mbox_chan *chan; + struct brcm_message mssg; u32 len, rx_status; u32 num_frags; int i; @@ -599,29 +595,23 @@ pdc_receive(struct pdc_state *pdcs, struct brcm_message *mssg) u32 rx_idx; /* ring index of start of receive frame */ dma_addr_t resp_hdr_daddr; + mbc = &pdcs->mbc; + chan = &mbc->chans[0]; + mssg.type = BRCM_MESSAGE_SPU; + /* * return if a complete response message is not yet ready. * rxin_numd[rxin] is the number of fragments in the next msg * to read. */ frags_rdy = NRXDACTIVE(pdcs->rxin, pdcs->last_rx_curr, pdcs->nrxpost); - if ((frags_rdy == 0) || (frags_rdy < pdcs->rxin_numd[pdcs->rxin])) { - /* See if the hw has written more fragments than we know */ - pdcs->last_rx_curr = - (ioread32((void *)&pdcs->rxregs_64->status0) & - CRYPTO_D64_RS0_CD_MASK) / RING_ENTRY_SIZE; - frags_rdy = NRXDACTIVE(pdcs->rxin, pdcs->last_rx_curr, - pdcs->nrxpost); - if ((frags_rdy == 0) || - (frags_rdy < pdcs->rxin_numd[pdcs->rxin])) { - /* No response ready */ - return -EAGAIN; - } - /* can't read descriptors/data until write index is read */ - rmb(); - } + if ((frags_rdy == 0) || (frags_rdy < pdcs->rxin_numd[pdcs->rxin])) + /* No response ready */ + return -EAGAIN; num_frags = pdcs->txin_numd[pdcs->txin]; + WARN_ON(num_frags == 0); + dma_unmap_sg(dev, pdcs->src_sg[pdcs->txin], sg_nents(pdcs->src_sg[pdcs->txin]), DMA_TO_DEVICE); @@ -634,7 +624,7 @@ pdc_receive(struct pdc_state *pdcs, struct brcm_message *mssg) rx_idx = pdcs->rxin; num_frags = pdcs->rxin_numd[rx_idx]; /* Return opaque context with result */ - mssg->ctx = pdcs->rxp_ctx[rx_idx]; + mssg.ctx = pdcs->rxp_ctx[rx_idx]; pdcs->rxp_ctx[rx_idx] = NULL; resp_hdr = pdcs->resp_hdr[rx_idx]; resp_hdr_daddr = pdcs->resp_hdr_daddr[rx_idx]; @@ -674,12 +664,35 @@ pdc_receive(struct pdc_state *pdcs, struct brcm_message *mssg) dma_pool_free(pdcs->rx_buf_pool, resp_hdr, resp_hdr_daddr); + mbox_chan_received_data(chan, &mssg); + pdcs->pdc_replies++; - /* if we read one or more rx descriptors, claim success */ - if (num_frags > 0) - return PDC_SUCCESS; - else - return -EIO; + return PDC_SUCCESS; +} + +/** + * pdc_receive() - Process as many responses as are available in the rx ring. + * @pdcs: PDC state + * + * Called within the hard IRQ. + * Return: + */ +static int +pdc_receive(struct pdc_state *pdcs) +{ + int rx_status; + + /* read last_rx_curr from register once */ + pdcs->last_rx_curr = + (ioread32((void *)&pdcs->rxregs_64->status0) & + CRYPTO_D64_RS0_CD_MASK) / RING_ENTRY_SIZE; + + do { + /* Could be many frames ready */ + rx_status = pdc_receive_one(pdcs); + } while (rx_status == PDC_SUCCESS); + + return 0; } /** @@ -946,14 +959,13 @@ static irqreturn_t pdc_irq_handler(int irq, void *cookie) } /** - * pdc_irq_thread() - Function invoked on deferred thread when a DMA tx has - * completed or data is available to receive. + * pdc_irq_thread() - Function invoked on deferred thread when data is available + * to receive. * @irq: Interrupt number * @cookie: PDC state for PDC that generated the interrupt * - * On DMA tx complete, notify the mailbox client. On DMA rx complete, process - * as many SPU response messages as are available and send each to the mailbox - * client. + * On DMA rx complete, process as many SPU response messages as are available + * and send each to the mailbox client. * * Return: IRQ_HANDLED if we recognized and handled the interrupt * IRQ_NONE otherwise @@ -961,39 +973,15 @@ static irqreturn_t pdc_irq_handler(int irq, void *cookie) static irqreturn_t pdc_irq_thread(int irq, void *cookie) { struct pdc_state *pdcs = cookie; - struct mbox_controller *mbc; - struct mbox_chan *chan; bool rx_int; - int rx_status; - struct brcm_message mssg; rx_int = test_and_clear_bit(PDC_RCVINT_0, &pdcs->intstatus); - if (pdcs && rx_int) { dev_dbg(&pdcs->pdev->dev, "%s() got irq %d with rx_int %s", __func__, irq, rx_int ? "set" : "clear"); - mbc = &pdcs->mbc; - chan = &mbc->chans[0]; - - while (1) { - /* Could be many frames ready */ - memset(&mssg, 0, sizeof(mssg)); - mssg.type = BRCM_MESSAGE_SPU; - rx_status = pdc_receive(pdcs, &mssg); - if (rx_status >= 0) { - dev_dbg(&pdcs->pdev->dev, - "%s(): invoking client rx cb", - __func__); - mbox_chan_received_data(chan, &mssg); - } else { - dev_dbg(&pdcs->pdev->dev, - "%s(): no SPU response available", - __func__); - break; - } - } + pdc_receive(pdcs); return IRQ_HANDLED; } return IRQ_NONE; -- cgit v1.2.3