Re: [Qemu-devel] [PATCH 05/14] eepro100: Use PCI DMA stub functions

["Michael S. Tsirkin" <mst@redhat.com>]

On Tue, Nov 01, 2011 at 03:24:28PM -0500, Anthony Liguori wrote:
> On 10/31/2011 11:45 AM, Stefan Weil wrote:
> >Am 31.10.2011 07:06, schrieb David Gibson:
> >>From: Eduard - Gabriel Munteanu<eduard.munteanu@linux360.ro>
> >>
> >>This updates the eepro100 device emulation to use the explicit PCI DMA
> >>functions, instead of directly calling physical memory access functions.
> >>
> >>Signed-off-by: Eduard - Gabriel Munteanu<eduard.munteanu@linux360.ro>
> >>Signed-off-by: David Gibson<dwg@au1.ibm.com>
> >>Signed-off-by: Alexey Kardashevskiy<aik@ozlabs.ru>
> >>---
> >>hw/eepro100.c | 121 +++++++++++++++++++++++----------------------------------
> >>1 files changed, 49 insertions(+), 72 deletions(-)
> >>
> >>diff --git a/hw/eepro100.c b/hw/eepro100.c
> >>index 4e3c52f..7d59e71 100644
> >>--- a/hw/eepro100.c
> >>+++ b/hw/eepro100.c
> >>@@ -46,6 +46,7 @@
> >>#include "net.h"
> >>#include "eeprom93xx.h"
> >>#include "sysemu.h"
> >>+#include "dma.h"
> >>
> >>/* QEMU sends frames smaller than 60 bytes to ethernet nics.
> >>* Such frames are rejected by real nics and their emulations.
> >>@@ -315,38 +316,6 @@ static const uint16_t eepro100_mdi_mask[] = {
> >>0xffff, 0xffff, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,
> >>};
> >>
> >>-/* Read a 16 bit little endian value from physical memory. */
> >>-static uint16_t e100_ldw_le_phys(target_phys_addr_t addr)
> >>-{
> >>- /* Load 16 bit (little endian) word from emulated hardware. */
> >>- uint16_t val;
> >>- cpu_physical_memory_read(addr,&val, sizeof(val));
> >>- return le16_to_cpu(val);
> >>-}
> >>-
> >>-/* Read a 32 bit little endian value from physical memory. */
> >>-static uint32_t e100_ldl_le_phys(target_phys_addr_t addr)
> >>-{
> >>- /* Load 32 bit (little endian) word from emulated hardware. */
> >>- uint32_t val;
> >>- cpu_physical_memory_read(addr,&val, sizeof(val));
> >>- return le32_to_cpu(val);
> >>-}
> >>-
> >>-/* Write a 16 bit little endian value to physical memory. */
> >>-static void e100_stw_le_phys(target_phys_addr_t addr, uint16_t val)
> >>-{
> >>- val = cpu_to_le16(val);
> >>- cpu_physical_memory_write(addr,&val, sizeof(val));
> >>-}
> >>-
> >>-/* Write a 32 bit little endian value to physical memory. */
> >>-static void e100_stl_le_phys(target_phys_addr_t addr, uint32_t val)
> >>-{
> >>- val = cpu_to_le32(val);
> >>- cpu_physical_memory_write(addr,&val, sizeof(val));
> >>-}
> >>-
> >>#define POLYNOMIAL 0x04c11db6
> >>
> >>/* From FreeBSD */
> >>@@ -744,21 +713,26 @@ static void dump_statistics(EEPRO100State * s)
> >>* values which really matter.
> >>* Number of data should check configuration!!!
> >>*/
> >>- cpu_physical_memory_write(s->statsaddr,&s->statistics, s->stats_size);
> >>- e100_stl_le_phys(s->statsaddr + 0, s->statistics.tx_good_frames);
> >>- e100_stl_le_phys(s->statsaddr + 36, s->statistics.rx_good_frames);
> >>- e100_stl_le_phys(s->statsaddr + 48, s->statistics.rx_resource_errors);
> >>- e100_stl_le_phys(s->statsaddr + 60, s->statistics.rx_short_frame_errors);
> >>+ pci_dma_write(&s->dev, s->statsaddr,
> >>+ (uint8_t *)&s->statistics, s->stats_size);
> >The type cast is not needed and should be removed.
> >>+ stl_le_pci_dma(&s->dev, s->statsaddr + 0,
> >>+ s->statistics.tx_good_frames);
> >>+ stl_le_pci_dma(&s->dev, s->statsaddr + 36,
> >>+ s->statistics.rx_good_frames);
> >>+ stl_le_pci_dma(&s->dev, s->statsaddr + 48,
> >>+ s->statistics.rx_resource_errors);
> >>+ stl_le_pci_dma(&s->dev, s->statsaddr + 60,
> >>+ s->statistics.rx_short_frame_errors);
> >>#if 0
> >>- e100_stw_le_phys(s->statsaddr + 76, s->statistics.xmt_tco_frames);
> >>- e100_stw_le_phys(s->statsaddr + 78, s->statistics.rcv_tco_frames);
> >>+ stw_le_pci_dma(&s->dev, s->statsaddr + 76, s->statistics.xmt_tco_frames);
> >>+ stw_le_pci_dma(&s->dev, s->statsaddr + 78, s->statistics.rcv_tco_frames);
> >>missing("CU dump statistical counters");
> >>#endif
> >>}
> >>
> >>static void read_cb(EEPRO100State *s)
> >>{
> >>- cpu_physical_memory_read(s->cb_address,&s->tx, sizeof(s->tx));
> >>+ pci_dma_read(&s->dev, s->cb_address, (uint8_t *)&s->tx, sizeof(s->tx));
> >The type cast is not needed and should be removed.
> >>s->tx.status = le16_to_cpu(s->tx.status);
> >>s->tx.command = le16_to_cpu(s->tx.command);
> >>s->tx.link = le32_to_cpu(s->tx.link);
> >>@@ -788,18 +762,17 @@ static void tx_command(EEPRO100State *s)
> >>}
> >>assert(tcb_bytes<= sizeof(buf));
> >>while (size< tcb_bytes) {
> >>- uint32_t tx_buffer_address = e100_ldl_le_phys(tbd_address);
> >>- uint16_t tx_buffer_size = e100_ldw_le_phys(tbd_address + 4);
> >>+ uint32_t tx_buffer_address = ldl_le_pci_dma(&s->dev, tbd_address);
> >>+ uint16_t tx_buffer_size = lduw_le_pci_dma(&s->dev, tbd_address + 4);
> >>#if 0
> >>- uint16_t tx_buffer_el = e100_ldw_le_phys(tbd_address + 6);
> >>+ uint16_t tx_buffer_el = lduw_le_pci_dma(&s->dev, tbd_address + 6);
> >>#endif
> >>tbd_address += 8;
> >>TRACE(RXTX, logout
> >>("TBD (simplified mode): buffer address 0x%08x, size 0x%04x\n",
> >>tx_buffer_address, tx_buffer_size));
> >>tx_buffer_size = MIN(tx_buffer_size, sizeof(buf) - size);
> >>- cpu_physical_memory_read(tx_buffer_address,&buf[size],
> >>- tx_buffer_size);
> >>+ pci_dma_read(&s->dev, tx_buffer_address,&buf[size], tx_buffer_size);
> >>size += tx_buffer_size;
> >>}
> >>if (tbd_array == 0xffffffff) {
> >>@@ -810,16 +783,19 @@ static void tx_command(EEPRO100State *s)
> >>if (s->has_extended_tcb_support&& !(s->configuration[6]& BIT(4))) {
> >>/* Extended Flexible TCB. */
> >>for (; tbd_count< 2; tbd_count++) {
> >>- uint32_t tx_buffer_address = e100_ldl_le_phys(tbd_address);
> >>- uint16_t tx_buffer_size = e100_ldw_le_phys(tbd_address + 4);
> >>- uint16_t tx_buffer_el = e100_ldw_le_phys(tbd_address + 6);
> >>+ uint32_t tx_buffer_address = ldl_le_pci_dma(&s->dev,
> >>+ tbd_address);
> >>+ uint16_t tx_buffer_size = lduw_le_pci_dma(&s->dev,
> >>+ tbd_address + 4);
> >>+ uint16_t tx_buffer_el = lduw_le_pci_dma(&s->dev,
> >>+ tbd_address + 6);
> >>tbd_address += 8;
> >>TRACE(RXTX, logout
> >>("TBD (extended flexible mode): buffer address 0x%08x, size 0x%04x\n",
> >>tx_buffer_address, tx_buffer_size));
> >>tx_buffer_size = MIN(tx_buffer_size, sizeof(buf) - size);
> >>- cpu_physical_memory_read(tx_buffer_address,&buf[size],
> >>- tx_buffer_size);
> >>+ pci_dma_read(&s->dev, tx_buffer_address,
> >>+&buf[size], tx_buffer_size);
> >>size += tx_buffer_size;
> >>if (tx_buffer_el& 1) {
> >>break;
> >>@@ -828,16 +804,16 @@ static void tx_command(EEPRO100State *s)
> >>}
> >>tbd_address = tbd_array;
> >>for (; tbd_count< s->tx.tbd_count; tbd_count++) {
> >>- uint32_t tx_buffer_address = e100_ldl_le_phys(tbd_address);
> >>- uint16_t tx_buffer_size = e100_ldw_le_phys(tbd_address + 4);
> >>- uint16_t tx_buffer_el = e100_ldw_le_phys(tbd_address + 6);
> >>+ uint32_t tx_buffer_address = ldl_le_pci_dma(&s->dev, tbd_address);
> >>+ uint16_t tx_buffer_size = lduw_le_pci_dma(&s->dev, tbd_address + 4);
> >>+ uint16_t tx_buffer_el = lduw_le_pci_dma(&s->dev, tbd_address + 6);
> >>tbd_address += 8;
> >>TRACE(RXTX, logout
> >>("TBD (flexible mode): buffer address 0x%08x, size 0x%04x\n",
> >>tx_buffer_address, tx_buffer_size));
> >>tx_buffer_size = MIN(tx_buffer_size, sizeof(buf) - size);
> >>- cpu_physical_memory_read(tx_buffer_address,&buf[size],
> >>- tx_buffer_size);
> >>+ pci_dma_read(&s->dev, tx_buffer_address,
> >>+&buf[size], tx_buffer_size);
> >>size += tx_buffer_size;
> >>if (tx_buffer_el& 1) {
> >>break;
> >>@@ -862,7 +838,7 @@ static void set_multicast_list(EEPRO100State *s)
> >>TRACE(OTHER, logout("multicast list, multicast count = %u\n", multicast_count));
> >>for (i = 0; i< multicast_count; i += 6) {
> >>uint8_t multicast_addr[6];
> >>- cpu_physical_memory_read(s->cb_address + 10 + i, multicast_addr, 6);
> >>+ pci_dma_read(&s->dev, s->cb_address + 10 + i, multicast_addr, 6);
> >>TRACE(OTHER, logout("multicast entry %s\n", nic_dump(multicast_addr, 6)));
> >>unsigned mcast_idx = compute_mcast_idx(multicast_addr);
> >>assert(mcast_idx< 64);
> >>@@ -896,12 +872,12 @@ static void action_command(EEPRO100State *s)
> >>/* Do nothing. */
> >>break;
> >>case CmdIASetup:
> >>- cpu_physical_memory_read(s->cb_address + 8,&s->conf.macaddr.a[0], 6);
> >>+ pci_dma_read(&s->dev, s->cb_address + 8,&s->conf.macaddr.a[0], 6);
> >>TRACE(OTHER, logout("macaddr: %s\n", nic_dump(&s->conf.macaddr.a[0], 6)));
> >>break;
> >>case CmdConfigure:
> >>- cpu_physical_memory_read(s->cb_address + 8,&s->configuration[0],
> >>- sizeof(s->configuration));
> >>+ pci_dma_read(&s->dev, s->cb_address + 8,
> >>+&s->configuration[0], sizeof(s->configuration));
> >>TRACE(OTHER, logout("configuration: %s\n",
> >>nic_dump(&s->configuration[0], 16)));
> >>TRACE(OTHER, logout("configuration: %s\n",
> >>@@ -938,7 +914,8 @@ static void action_command(EEPRO100State *s)
> >>break;
> >>}
> >>/* Write new status. */
> >>- e100_stw_le_phys(s->cb_address, s->tx.status | ok_status | STATUS_C);
> >>+ stw_le_pci_dma(&s->dev, s->cb_address,
> >>+ s->tx.status | ok_status | STATUS_C);
> >>if (bit_i) {
> >>/* CU completed action. */
> >>eepro100_cx_interrupt(s);
> >>@@ -1005,7 +982,7 @@ static void eepro100_cu_command(EEPRO100State * s,
> >>uint8_t val)
> >>/* Dump statistical counters. */
> >>TRACE(OTHER, logout("val=0x%02x (dump stats)\n", val));
> >>dump_statistics(s);
> >>- e100_stl_le_phys(s->statsaddr + s->stats_size, 0xa005);
> >>+ stl_le_pci_dma(&s->dev, s->statsaddr + s->stats_size, 0xa005);
> >>break;
> >>case CU_CMD_BASE:
> >>/* Load CU base. */
> >>@@ -1016,7 +993,7 @@ static void eepro100_cu_command(EEPRO100State * s,
> >>uint8_t val)
> >>/* Dump and reset statistical counters. */
> >>TRACE(OTHER, logout("val=0x%02x (dump stats and reset)\n", val));
> >>dump_statistics(s);
> >>- e100_stl_le_phys(s->statsaddr + s->stats_size, 0xa007);
> >>+ stl_le_pci_dma(&s->dev, s->statsaddr + s->stats_size, 0xa007);
> >>memset(&s->statistics, 0, sizeof(s->statistics));
> >>break;
> >>case CU_SRESUME:
> >>@@ -1310,10 +1287,10 @@ static void eepro100_write_port(EEPRO100State *s)
> >>case PORT_SELFTEST:
> >>TRACE(OTHER, logout("selftest address=0x%08x\n", address));
> >>eepro100_selftest_t data;
> >>- cpu_physical_memory_read(address,&data, sizeof(data));
> >>+ pci_dma_read(&s->dev, address, (uint8_t *)&data, sizeof(data));
> >The type cast is not needed and should be removed.
> >>data.st_sign = 0xffffffff;
> >>data.st_result = 0;
> >>- cpu_physical_memory_write(address,&data, sizeof(data));
> >>+ pci_dma_write(&s->dev, address, (uint8_t *)&data, sizeof(data));
> >The type cast is not needed and should be removed.
> >>break;
> >>case PORT_SELECTIVE_RESET:
> >>TRACE(OTHER, logout("selective reset, selftest address=0x%08x\n", address));
> >>@@ -1729,8 +1706,8 @@ static ssize_t nic_receive(VLANClientState *nc, const
> >>uint8_t * buf, size_t size
> >>}
> >>/* !!! */
> >>eepro100_rx_t rx;
> >>- cpu_physical_memory_read(s->ru_base + s->ru_offset,&rx,
> >>- sizeof(eepro100_rx_t));
> >>+ pci_dma_read(&s->dev, s->ru_base + s->ru_offset,
> >>+ (uint8_t *)&rx, sizeof(eepro100_rx_t));
> >
> >The type cast is not needed and should be removed.
> >
> >
> >>uint16_t rfd_command = le16_to_cpu(rx.command);
> >>uint16_t rfd_size = le16_to_cpu(rx.size);
> >>
> >>@@ -1746,10 +1723,10 @@ static ssize_t nic_receive(VLANClientState *nc, const
> >>uint8_t * buf, size_t size
> >>#endif
> >>TRACE(OTHER, logout("command 0x%04x, link 0x%08x, addr 0x%08x, size %u\n",
> >>rfd_command, rx.link, rx.rx_buf_addr, rfd_size));
> >>- e100_stw_le_phys(s->ru_base + s->ru_offset +
> >>- offsetof(eepro100_rx_t, status), rfd_status);
> >>- e100_stw_le_phys(s->ru_base + s->ru_offset +
> >>- offsetof(eepro100_rx_t, count), size);
> >>+ stw_le_pci_dma(&s->dev, s->ru_base + s->ru_offset +
> >>+ offsetof(eepro100_rx_t, status), rfd_status);
> >>+ stw_le_pci_dma(&s->dev, s->ru_base + s->ru_offset +
> >>+ offsetof(eepro100_rx_t, count), size);
> >>/* Early receive interrupt not supported. */
> >>#if 0
> >>eepro100_er_interrupt(s);
> >>@@ -1763,8 +1740,8 @@ static ssize_t nic_receive(VLANClientState *nc, const
> >>uint8_t * buf, size_t size
> >>#if 0
> >>assert(!(s->configuration[17]& BIT(0)));
> >>#endif
> >>- cpu_physical_memory_write(s->ru_base + s->ru_offset +
> >>- sizeof(eepro100_rx_t), buf, size);
> >>+ pci_dma_write(&s->dev, s->ru_base + s->ru_offset +
> >>+ sizeof(eepro100_rx_t), buf, size);
> >>s->statistics.rx_good_frames++;
> >>eepro100_fr_interrupt(s);
> >>s->ru_offset = le32_to_cpu(rx.link);
> >
> >
> >Hi,
> >
> >the patch looks reasonable. I only suggest a formal change:
> >
> >There are lots of unnecessary type casts in several of your patches.
> >I marked them here, but they should be removed anywhere.
> 
> Agreed.  However, I'm going to apply this series as I'd like to get
> it in for the freeze.

What does it get us, applying it before freeze?
It's an api change without new functionality.
Seems better on -next branch.

>  But David, please follow up with a patch to
> remove the unnecessary type casts.
> 
> Regards,
> 
> Anthony Liguori
> 
> >
> >Kind regards,
> >Stefan
> >
> >
> >