From 50b0df814b0f75c08a3d45a017016a75af3edb5d Mon Sep 17 00:00:00 2001 From: Alexey Brodkin Date: Wed, 22 Jan 2014 20:49:09 +0400 Subject: [PATCH] net/designware: make driver compatible with data cache Up until now this driver only worked with data cache disabled. To make it work with enabled data cache following changes were required: * Flush Tx/Rx buffer descriptors their modification * Invalidate Tx/Rx buffer descriptors before reading its values * Flush cache for data passed from CPU to GMAC * Invalidate cache for data passed from GMAC to CPU Cc: Joe Hershberger Cc: Vipin Kumar Cc: Stefan Roese Cc: Mischa Jonker Cc: Shiraz Hashim Cc: Albert ARIBAUD Cc: Amit Virdi Cc: Sonic Zhang Signed-off-by: Alexey Brodkin --- drivers/net/designware.c | 53 +++++++++++++++++++++++++++++++++++++--- 1 file changed, 50 insertions(+), 3 deletions(-) diff --git a/drivers/net/designware.c b/drivers/net/designware.c index 44c1e350ce..c45593bcc0 100644 --- a/drivers/net/designware.c +++ b/drivers/net/designware.c @@ -119,6 +119,11 @@ static void tx_descs_init(struct eth_device *dev) /* Correcting the last pointer of the chain */ desc_p->dmamac_next = &desc_table_p[0]; + /* Flush all Tx buffer descriptors at once */ + flush_dcache_range((unsigned int)priv->tx_mac_descrtable, + (unsigned int)priv->tx_mac_descrtable + + sizeof(priv->tx_mac_descrtable)); + writel((ulong)&desc_table_p[0], &dma_p->txdesclistaddr); priv->tx_currdescnum = 0; } @@ -132,6 +137,15 @@ static void rx_descs_init(struct eth_device *dev) struct dmamacdescr *desc_p; u32 idx; + /* Before passing buffers to GMAC we need to make sure zeros + * written there right after "priv" structure allocation were + * flushed into RAM. + * Otherwise there's a chance to get some of them flushed in RAM when + * GMAC is already pushing data to RAM via DMA. This way incoming from + * GMAC data will be corrupted. */ + flush_dcache_range((unsigned int)rxbuffs, (unsigned int)rxbuffs + + RX_TOTAL_BUFSIZE); + for (idx = 0; idx < CONFIG_RX_DESCR_NUM; idx++) { desc_p = &desc_table_p[idx]; desc_p->dmamac_addr = &rxbuffs[idx * CONFIG_ETH_BUFSIZE]; @@ -147,6 +161,11 @@ static void rx_descs_init(struct eth_device *dev) /* Correcting the last pointer of the chain */ desc_p->dmamac_next = &desc_table_p[0]; + /* Flush all Rx buffer descriptors at once */ + flush_dcache_range((unsigned int)priv->rx_mac_descrtable, + (unsigned int)priv->rx_mac_descrtable + + sizeof(priv->rx_mac_descrtable)); + writel((ulong)&desc_table_p[0], &dma_p->rxdesclistaddr); priv->rx_currdescnum = 0; } @@ -261,6 +280,11 @@ static int dw_eth_send(struct eth_device *dev, void *packet, int length) u32 desc_num = priv->tx_currdescnum; struct dmamacdescr *desc_p = &priv->tx_mac_descrtable[desc_num]; + /* Invalidate only "status" field for the following check */ + invalidate_dcache_range((unsigned long)&desc_p->txrx_status, + (unsigned long)&desc_p->txrx_status + + sizeof(desc_p->txrx_status)); + /* Check if the descriptor is owned by CPU */ if (desc_p->txrx_status & DESC_TXSTS_OWNBYDMA) { printf("CPU not owner of tx frame\n"); @@ -269,6 +293,10 @@ static int dw_eth_send(struct eth_device *dev, void *packet, int length) memcpy((void *)desc_p->dmamac_addr, packet, length); + /* Flush data to be sent */ + flush_dcache_range((unsigned long)desc_p->dmamac_addr, + (unsigned long)desc_p->dmamac_addr + length); + #if defined(CONFIG_DW_ALTDESCRIPTOR) desc_p->txrx_status |= DESC_TXSTS_TXFIRST | DESC_TXSTS_TXLAST; desc_p->dmamac_cntl |= (length << DESC_TXCTRL_SIZE1SHFT) & \ @@ -284,6 +312,10 @@ static int dw_eth_send(struct eth_device *dev, void *packet, int length) desc_p->txrx_status = DESC_TXSTS_OWNBYDMA; #endif + /* Flush modified buffer descriptor */ + flush_dcache_range((unsigned long)desc_p, + (unsigned long)desc_p + sizeof(struct dmamacdescr)); + /* Test the wrap-around condition. */ if (++desc_num >= CONFIG_TX_DESCR_NUM) desc_num = 0; @@ -299,18 +331,28 @@ static int dw_eth_send(struct eth_device *dev, void *packet, int length) static int dw_eth_recv(struct eth_device *dev) { struct dw_eth_dev *priv = dev->priv; - u32 desc_num = priv->rx_currdescnum; + u32 status, desc_num = priv->rx_currdescnum; struct dmamacdescr *desc_p = &priv->rx_mac_descrtable[desc_num]; - - u32 status = desc_p->txrx_status; int length = 0; + /* Invalidate entire buffer descriptor */ + invalidate_dcache_range((unsigned long)desc_p, + (unsigned long)desc_p + + sizeof(struct dmamacdescr)); + + status = desc_p->txrx_status; + /* Check if the owner is the CPU */ if (!(status & DESC_RXSTS_OWNBYDMA)) { length = (status & DESC_RXSTS_FRMLENMSK) >> \ DESC_RXSTS_FRMLENSHFT; + /* Invalidate received data */ + invalidate_dcache_range((unsigned long)desc_p->dmamac_addr, + (unsigned long)desc_p->dmamac_addr + + length); + NetReceive(desc_p->dmamac_addr, length); /* @@ -319,6 +361,11 @@ static int dw_eth_recv(struct eth_device *dev) */ desc_p->txrx_status |= DESC_RXSTS_OWNBYDMA; + /* Flush only status field - others weren't changed */ + flush_dcache_range((unsigned long)&desc_p->txrx_status, + (unsigned long)&desc_p->txrx_status + + sizeof(desc_p->txrx_status)); + /* Test the wrap-around condition. */ if (++desc_num >= CONFIG_RX_DESCR_NUM) desc_num = 0; -- 2.25.1