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authorEdward Cree <ecree@solarflare.com>2016-11-28 18:55:34 +0000
committerDavid S. Miller <davem@davemloft.net>2016-11-30 10:16:58 -0500
commit5a6681e22c1409089132085811857d6da828761b (patch)
tree3ba1f36288a43a6136ea62d366bbaead4ac150b6 /drivers/net/ethernet/sfc/falcon/nic.c
parentcpsw: ethtool: add support for nway reset (diff)
downloadlinux-dev-5a6681e22c1409089132085811857d6da828761b.tar.xz
linux-dev-5a6681e22c1409089132085811857d6da828761b.zip
sfc: separate out SFC4000 ("Falcon") support into new sfc-falcon driver
Rationale: The differences between Falcon and Siena are in many ways larger than those between Siena and EF10 (despite Siena being nominally "Falcon- architecture"); for instance, Falcon has no MCPU, so there is no MCDI. Removing Falcon support from the sfc driver should simplify the latter, and avoid the possibility of Falcon support being broken by changes to sfc (which are rarely if ever tested on Falcon, it being end-of-lifed hardware). The sfc-falcon driver created in this changeset is essentially a copy of the sfc driver, but with Siena- and EF10-specific code, including MCDI, removed and with the "efx_" identifier prefix changed to "ef4_" (for "EFX 4000- series") to avoid collisions when both drivers are built-in. This changeset removes Falcon from the sfc driver's PCI ID table; then in sfc I've removed obvious Falcon-related code: I removed the Falcon NIC functions, Falcon PHY code, and EFX_REV_FALCON_*, then fixed up everything that referenced them. Also, increment minor version of both drivers (to 4.1). For now, CONFIG_SFC selects CONFIG_SFC_FALCON, so that updating old configs doesn't cause Falcon support to disappear; but that should be undone at some point in the future. Signed-off-by: Edward Cree <ecree@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/ethernet/sfc/falcon/nic.c')
-rw-r--r--drivers/net/ethernet/sfc/falcon/nic.c527
1 files changed, 527 insertions, 0 deletions
diff --git a/drivers/net/ethernet/sfc/falcon/nic.c b/drivers/net/ethernet/sfc/falcon/nic.c
new file mode 100644
index 000000000000..a8ecb33390da
--- /dev/null
+++ b/drivers/net/ethernet/sfc/falcon/nic.c
@@ -0,0 +1,527 @@
+/****************************************************************************
+ * Driver for Solarflare network controllers and boards
+ * Copyright 2005-2006 Fen Systems Ltd.
+ * Copyright 2006-2013 Solarflare Communications Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation, incorporated herein by reference.
+ */
+
+#include <linux/bitops.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/pci.h>
+#include <linux/module.h>
+#include <linux/seq_file.h>
+#include <linux/cpu_rmap.h>
+#include "net_driver.h"
+#include "bitfield.h"
+#include "efx.h"
+#include "nic.h"
+#include "farch_regs.h"
+#include "io.h"
+#include "workarounds.h"
+
+/**************************************************************************
+ *
+ * Generic buffer handling
+ * These buffers are used for interrupt status, MAC stats, etc.
+ *
+ **************************************************************************/
+
+int ef4_nic_alloc_buffer(struct ef4_nic *efx, struct ef4_buffer *buffer,
+ unsigned int len, gfp_t gfp_flags)
+{
+ buffer->addr = dma_zalloc_coherent(&efx->pci_dev->dev, len,
+ &buffer->dma_addr, gfp_flags);
+ if (!buffer->addr)
+ return -ENOMEM;
+ buffer->len = len;
+ return 0;
+}
+
+void ef4_nic_free_buffer(struct ef4_nic *efx, struct ef4_buffer *buffer)
+{
+ if (buffer->addr) {
+ dma_free_coherent(&efx->pci_dev->dev, buffer->len,
+ buffer->addr, buffer->dma_addr);
+ buffer->addr = NULL;
+ }
+}
+
+/* Check whether an event is present in the eventq at the current
+ * read pointer. Only useful for self-test.
+ */
+bool ef4_nic_event_present(struct ef4_channel *channel)
+{
+ return ef4_event_present(ef4_event(channel, channel->eventq_read_ptr));
+}
+
+void ef4_nic_event_test_start(struct ef4_channel *channel)
+{
+ channel->event_test_cpu = -1;
+ smp_wmb();
+ channel->efx->type->ev_test_generate(channel);
+}
+
+int ef4_nic_irq_test_start(struct ef4_nic *efx)
+{
+ efx->last_irq_cpu = -1;
+ smp_wmb();
+ return efx->type->irq_test_generate(efx);
+}
+
+/* Hook interrupt handler(s)
+ * Try MSI and then legacy interrupts.
+ */
+int ef4_nic_init_interrupt(struct ef4_nic *efx)
+{
+ struct ef4_channel *channel;
+ unsigned int n_irqs;
+ int rc;
+
+ if (!EF4_INT_MODE_USE_MSI(efx)) {
+ rc = request_irq(efx->legacy_irq,
+ efx->type->irq_handle_legacy, IRQF_SHARED,
+ efx->name, efx);
+ if (rc) {
+ netif_err(efx, drv, efx->net_dev,
+ "failed to hook legacy IRQ %d\n",
+ efx->pci_dev->irq);
+ goto fail1;
+ }
+ return 0;
+ }
+
+#ifdef CONFIG_RFS_ACCEL
+ if (efx->interrupt_mode == EF4_INT_MODE_MSIX) {
+ efx->net_dev->rx_cpu_rmap =
+ alloc_irq_cpu_rmap(efx->n_rx_channels);
+ if (!efx->net_dev->rx_cpu_rmap) {
+ rc = -ENOMEM;
+ goto fail1;
+ }
+ }
+#endif
+
+ /* Hook MSI or MSI-X interrupt */
+ n_irqs = 0;
+ ef4_for_each_channel(channel, efx) {
+ rc = request_irq(channel->irq, efx->type->irq_handle_msi,
+ IRQF_PROBE_SHARED, /* Not shared */
+ efx->msi_context[channel->channel].name,
+ &efx->msi_context[channel->channel]);
+ if (rc) {
+ netif_err(efx, drv, efx->net_dev,
+ "failed to hook IRQ %d\n", channel->irq);
+ goto fail2;
+ }
+ ++n_irqs;
+
+#ifdef CONFIG_RFS_ACCEL
+ if (efx->interrupt_mode == EF4_INT_MODE_MSIX &&
+ channel->channel < efx->n_rx_channels) {
+ rc = irq_cpu_rmap_add(efx->net_dev->rx_cpu_rmap,
+ channel->irq);
+ if (rc)
+ goto fail2;
+ }
+#endif
+ }
+
+ return 0;
+
+ fail2:
+#ifdef CONFIG_RFS_ACCEL
+ free_irq_cpu_rmap(efx->net_dev->rx_cpu_rmap);
+ efx->net_dev->rx_cpu_rmap = NULL;
+#endif
+ ef4_for_each_channel(channel, efx) {
+ if (n_irqs-- == 0)
+ break;
+ free_irq(channel->irq, &efx->msi_context[channel->channel]);
+ }
+ fail1:
+ return rc;
+}
+
+void ef4_nic_fini_interrupt(struct ef4_nic *efx)
+{
+ struct ef4_channel *channel;
+
+#ifdef CONFIG_RFS_ACCEL
+ free_irq_cpu_rmap(efx->net_dev->rx_cpu_rmap);
+ efx->net_dev->rx_cpu_rmap = NULL;
+#endif
+
+ if (EF4_INT_MODE_USE_MSI(efx)) {
+ /* Disable MSI/MSI-X interrupts */
+ ef4_for_each_channel(channel, efx)
+ free_irq(channel->irq,
+ &efx->msi_context[channel->channel]);
+ } else {
+ /* Disable legacy interrupt */
+ free_irq(efx->legacy_irq, efx);
+ }
+}
+
+/* Register dump */
+
+#define REGISTER_REVISION_FA 1
+#define REGISTER_REVISION_FB 2
+#define REGISTER_REVISION_FC 3
+#define REGISTER_REVISION_FZ 3 /* last Falcon arch revision */
+#define REGISTER_REVISION_ED 4
+#define REGISTER_REVISION_EZ 4 /* latest EF10 revision */
+
+struct ef4_nic_reg {
+ u32 offset:24;
+ u32 min_revision:3, max_revision:3;
+};
+
+#define REGISTER(name, arch, min_rev, max_rev) { \
+ arch ## R_ ## min_rev ## max_rev ## _ ## name, \
+ REGISTER_REVISION_ ## arch ## min_rev, \
+ REGISTER_REVISION_ ## arch ## max_rev \
+}
+#define REGISTER_AA(name) REGISTER(name, F, A, A)
+#define REGISTER_AB(name) REGISTER(name, F, A, B)
+#define REGISTER_AZ(name) REGISTER(name, F, A, Z)
+#define REGISTER_BB(name) REGISTER(name, F, B, B)
+#define REGISTER_BZ(name) REGISTER(name, F, B, Z)
+#define REGISTER_CZ(name) REGISTER(name, F, C, Z)
+
+static const struct ef4_nic_reg ef4_nic_regs[] = {
+ REGISTER_AZ(ADR_REGION),
+ REGISTER_AZ(INT_EN_KER),
+ REGISTER_BZ(INT_EN_CHAR),
+ REGISTER_AZ(INT_ADR_KER),
+ REGISTER_BZ(INT_ADR_CHAR),
+ /* INT_ACK_KER is WO */
+ /* INT_ISR0 is RC */
+ REGISTER_AZ(HW_INIT),
+ REGISTER_CZ(USR_EV_CFG),
+ REGISTER_AB(EE_SPI_HCMD),
+ REGISTER_AB(EE_SPI_HADR),
+ REGISTER_AB(EE_SPI_HDATA),
+ REGISTER_AB(EE_BASE_PAGE),
+ REGISTER_AB(EE_VPD_CFG0),
+ /* EE_VPD_SW_CNTL and EE_VPD_SW_DATA are not used */
+ /* PMBX_DBG_IADDR and PBMX_DBG_IDATA are indirect */
+ /* PCIE_CORE_INDIRECT is indirect */
+ REGISTER_AB(NIC_STAT),
+ REGISTER_AB(GPIO_CTL),
+ REGISTER_AB(GLB_CTL),
+ /* FATAL_INTR_KER and FATAL_INTR_CHAR are partly RC */
+ REGISTER_BZ(DP_CTRL),
+ REGISTER_AZ(MEM_STAT),
+ REGISTER_AZ(CS_DEBUG),
+ REGISTER_AZ(ALTERA_BUILD),
+ REGISTER_AZ(CSR_SPARE),
+ REGISTER_AB(PCIE_SD_CTL0123),
+ REGISTER_AB(PCIE_SD_CTL45),
+ REGISTER_AB(PCIE_PCS_CTL_STAT),
+ /* DEBUG_DATA_OUT is not used */
+ /* DRV_EV is WO */
+ REGISTER_AZ(EVQ_CTL),
+ REGISTER_AZ(EVQ_CNT1),
+ REGISTER_AZ(EVQ_CNT2),
+ REGISTER_AZ(BUF_TBL_CFG),
+ REGISTER_AZ(SRM_RX_DC_CFG),
+ REGISTER_AZ(SRM_TX_DC_CFG),
+ REGISTER_AZ(SRM_CFG),
+ /* BUF_TBL_UPD is WO */
+ REGISTER_AZ(SRM_UPD_EVQ),
+ REGISTER_AZ(SRAM_PARITY),
+ REGISTER_AZ(RX_CFG),
+ REGISTER_BZ(RX_FILTER_CTL),
+ /* RX_FLUSH_DESCQ is WO */
+ REGISTER_AZ(RX_DC_CFG),
+ REGISTER_AZ(RX_DC_PF_WM),
+ REGISTER_BZ(RX_RSS_TKEY),
+ /* RX_NODESC_DROP is RC */
+ REGISTER_AA(RX_SELF_RST),
+ /* RX_DEBUG, RX_PUSH_DROP are not used */
+ REGISTER_CZ(RX_RSS_IPV6_REG1),
+ REGISTER_CZ(RX_RSS_IPV6_REG2),
+ REGISTER_CZ(RX_RSS_IPV6_REG3),
+ /* TX_FLUSH_DESCQ is WO */
+ REGISTER_AZ(TX_DC_CFG),
+ REGISTER_AA(TX_CHKSM_CFG),
+ REGISTER_AZ(TX_CFG),
+ /* TX_PUSH_DROP is not used */
+ REGISTER_AZ(TX_RESERVED),
+ REGISTER_BZ(TX_PACE),
+ /* TX_PACE_DROP_QID is RC */
+ REGISTER_BB(TX_VLAN),
+ REGISTER_BZ(TX_IPFIL_PORTEN),
+ REGISTER_AB(MD_TXD),
+ REGISTER_AB(MD_RXD),
+ REGISTER_AB(MD_CS),
+ REGISTER_AB(MD_PHY_ADR),
+ REGISTER_AB(MD_ID),
+ /* MD_STAT is RC */
+ REGISTER_AB(MAC_STAT_DMA),
+ REGISTER_AB(MAC_CTRL),
+ REGISTER_BB(GEN_MODE),
+ REGISTER_AB(MAC_MC_HASH_REG0),
+ REGISTER_AB(MAC_MC_HASH_REG1),
+ REGISTER_AB(GM_CFG1),
+ REGISTER_AB(GM_CFG2),
+ /* GM_IPG and GM_HD are not used */
+ REGISTER_AB(GM_MAX_FLEN),
+ /* GM_TEST is not used */
+ REGISTER_AB(GM_ADR1),
+ REGISTER_AB(GM_ADR2),
+ REGISTER_AB(GMF_CFG0),
+ REGISTER_AB(GMF_CFG1),
+ REGISTER_AB(GMF_CFG2),
+ REGISTER_AB(GMF_CFG3),
+ REGISTER_AB(GMF_CFG4),
+ REGISTER_AB(GMF_CFG5),
+ REGISTER_BB(TX_SRC_MAC_CTL),
+ REGISTER_AB(XM_ADR_LO),
+ REGISTER_AB(XM_ADR_HI),
+ REGISTER_AB(XM_GLB_CFG),
+ REGISTER_AB(XM_TX_CFG),
+ REGISTER_AB(XM_RX_CFG),
+ REGISTER_AB(XM_MGT_INT_MASK),
+ REGISTER_AB(XM_FC),
+ REGISTER_AB(XM_PAUSE_TIME),
+ REGISTER_AB(XM_TX_PARAM),
+ REGISTER_AB(XM_RX_PARAM),
+ /* XM_MGT_INT_MSK (note no 'A') is RC */
+ REGISTER_AB(XX_PWR_RST),
+ REGISTER_AB(XX_SD_CTL),
+ REGISTER_AB(XX_TXDRV_CTL),
+ /* XX_PRBS_CTL, XX_PRBS_CHK and XX_PRBS_ERR are not used */
+ /* XX_CORE_STAT is partly RC */
+};
+
+struct ef4_nic_reg_table {
+ u32 offset:24;
+ u32 min_revision:3, max_revision:3;
+ u32 step:6, rows:21;
+};
+
+#define REGISTER_TABLE_DIMENSIONS(_, offset, arch, min_rev, max_rev, step, rows) { \
+ offset, \
+ REGISTER_REVISION_ ## arch ## min_rev, \
+ REGISTER_REVISION_ ## arch ## max_rev, \
+ step, rows \
+}
+#define REGISTER_TABLE(name, arch, min_rev, max_rev) \
+ REGISTER_TABLE_DIMENSIONS( \
+ name, arch ## R_ ## min_rev ## max_rev ## _ ## name, \
+ arch, min_rev, max_rev, \
+ arch ## R_ ## min_rev ## max_rev ## _ ## name ## _STEP, \
+ arch ## R_ ## min_rev ## max_rev ## _ ## name ## _ROWS)
+#define REGISTER_TABLE_AA(name) REGISTER_TABLE(name, F, A, A)
+#define REGISTER_TABLE_AZ(name) REGISTER_TABLE(name, F, A, Z)
+#define REGISTER_TABLE_BB(name) REGISTER_TABLE(name, F, B, B)
+#define REGISTER_TABLE_BZ(name) REGISTER_TABLE(name, F, B, Z)
+#define REGISTER_TABLE_BB_CZ(name) \
+ REGISTER_TABLE_DIMENSIONS(name, FR_BZ_ ## name, F, B, B, \
+ FR_BZ_ ## name ## _STEP, \
+ FR_BB_ ## name ## _ROWS), \
+ REGISTER_TABLE_DIMENSIONS(name, FR_BZ_ ## name, F, C, Z, \
+ FR_BZ_ ## name ## _STEP, \
+ FR_CZ_ ## name ## _ROWS)
+#define REGISTER_TABLE_CZ(name) REGISTER_TABLE(name, F, C, Z)
+
+static const struct ef4_nic_reg_table ef4_nic_reg_tables[] = {
+ /* DRIVER is not used */
+ /* EVQ_RPTR, TIMER_COMMAND, USR_EV and {RX,TX}_DESC_UPD are WO */
+ REGISTER_TABLE_BB(TX_IPFIL_TBL),
+ REGISTER_TABLE_BB(TX_SRC_MAC_TBL),
+ REGISTER_TABLE_AA(RX_DESC_PTR_TBL_KER),
+ REGISTER_TABLE_BB_CZ(RX_DESC_PTR_TBL),
+ REGISTER_TABLE_AA(TX_DESC_PTR_TBL_KER),
+ REGISTER_TABLE_BB_CZ(TX_DESC_PTR_TBL),
+ REGISTER_TABLE_AA(EVQ_PTR_TBL_KER),
+ REGISTER_TABLE_BB_CZ(EVQ_PTR_TBL),
+ /* We can't reasonably read all of the buffer table (up to 8MB!).
+ * However this driver will only use a few entries. Reading
+ * 1K entries allows for some expansion of queue count and
+ * size before we need to change the version. */
+ REGISTER_TABLE_DIMENSIONS(BUF_FULL_TBL_KER, FR_AA_BUF_FULL_TBL_KER,
+ F, A, A, 8, 1024),
+ REGISTER_TABLE_DIMENSIONS(BUF_FULL_TBL, FR_BZ_BUF_FULL_TBL,
+ F, B, Z, 8, 1024),
+ REGISTER_TABLE_CZ(RX_MAC_FILTER_TBL0),
+ REGISTER_TABLE_BB_CZ(TIMER_TBL),
+ REGISTER_TABLE_BB_CZ(TX_PACE_TBL),
+ REGISTER_TABLE_BZ(RX_INDIRECTION_TBL),
+ /* TX_FILTER_TBL0 is huge and not used by this driver */
+ REGISTER_TABLE_CZ(TX_MAC_FILTER_TBL0),
+ REGISTER_TABLE_CZ(MC_TREG_SMEM),
+ /* MSIX_PBA_TABLE is not mapped */
+ /* SRM_DBG is not mapped (and is redundant with BUF_FLL_TBL) */
+ REGISTER_TABLE_BZ(RX_FILTER_TBL0),
+};
+
+size_t ef4_nic_get_regs_len(struct ef4_nic *efx)
+{
+ const struct ef4_nic_reg *reg;
+ const struct ef4_nic_reg_table *table;
+ size_t len = 0;
+
+ for (reg = ef4_nic_regs;
+ reg < ef4_nic_regs + ARRAY_SIZE(ef4_nic_regs);
+ reg++)
+ if (efx->type->revision >= reg->min_revision &&
+ efx->type->revision <= reg->max_revision)
+ len += sizeof(ef4_oword_t);
+
+ for (table = ef4_nic_reg_tables;
+ table < ef4_nic_reg_tables + ARRAY_SIZE(ef4_nic_reg_tables);
+ table++)
+ if (efx->type->revision >= table->min_revision &&
+ efx->type->revision <= table->max_revision)
+ len += table->rows * min_t(size_t, table->step, 16);
+
+ return len;
+}
+
+void ef4_nic_get_regs(struct ef4_nic *efx, void *buf)
+{
+ const struct ef4_nic_reg *reg;
+ const struct ef4_nic_reg_table *table;
+
+ for (reg = ef4_nic_regs;
+ reg < ef4_nic_regs + ARRAY_SIZE(ef4_nic_regs);
+ reg++) {
+ if (efx->type->revision >= reg->min_revision &&
+ efx->type->revision <= reg->max_revision) {
+ ef4_reado(efx, (ef4_oword_t *)buf, reg->offset);
+ buf += sizeof(ef4_oword_t);
+ }
+ }
+
+ for (table = ef4_nic_reg_tables;
+ table < ef4_nic_reg_tables + ARRAY_SIZE(ef4_nic_reg_tables);
+ table++) {
+ size_t size, i;
+
+ if (!(efx->type->revision >= table->min_revision &&
+ efx->type->revision <= table->max_revision))
+ continue;
+
+ size = min_t(size_t, table->step, 16);
+
+ for (i = 0; i < table->rows; i++) {
+ switch (table->step) {
+ case 4: /* 32-bit SRAM */
+ ef4_readd(efx, buf, table->offset + 4 * i);
+ break;
+ case 8: /* 64-bit SRAM */
+ ef4_sram_readq(efx,
+ efx->membase + table->offset,
+ buf, i);
+ break;
+ case 16: /* 128-bit-readable register */
+ ef4_reado_table(efx, buf, table->offset, i);
+ break;
+ case 32: /* 128-bit register, interleaved */
+ ef4_reado_table(efx, buf, table->offset, 2 * i);
+ break;
+ default:
+ WARN_ON(1);
+ return;
+ }
+ buf += size;
+ }
+ }
+}
+
+/**
+ * ef4_nic_describe_stats - Describe supported statistics for ethtool
+ * @desc: Array of &struct ef4_hw_stat_desc describing the statistics
+ * @count: Length of the @desc array
+ * @mask: Bitmask of which elements of @desc are enabled
+ * @names: Buffer to copy names to, or %NULL. The names are copied
+ * starting at intervals of %ETH_GSTRING_LEN bytes.
+ *
+ * Returns the number of visible statistics, i.e. the number of set
+ * bits in the first @count bits of @mask for which a name is defined.
+ */
+size_t ef4_nic_describe_stats(const struct ef4_hw_stat_desc *desc, size_t count,
+ const unsigned long *mask, u8 *names)
+{
+ size_t visible = 0;
+ size_t index;
+
+ for_each_set_bit(index, mask, count) {
+ if (desc[index].name) {
+ if (names) {
+ strlcpy(names, desc[index].name,
+ ETH_GSTRING_LEN);
+ names += ETH_GSTRING_LEN;
+ }
+ ++visible;
+ }
+ }
+
+ return visible;
+}
+
+/**
+ * ef4_nic_update_stats - Convert statistics DMA buffer to array of u64
+ * @desc: Array of &struct ef4_hw_stat_desc describing the DMA buffer
+ * layout. DMA widths of 0, 16, 32 and 64 are supported; where
+ * the width is specified as 0 the corresponding element of
+ * @stats is not updated.
+ * @count: Length of the @desc array
+ * @mask: Bitmask of which elements of @desc are enabled
+ * @stats: Buffer to update with the converted statistics. The length
+ * of this array must be at least @count.
+ * @dma_buf: DMA buffer containing hardware statistics
+ * @accumulate: If set, the converted values will be added rather than
+ * directly stored to the corresponding elements of @stats
+ */
+void ef4_nic_update_stats(const struct ef4_hw_stat_desc *desc, size_t count,
+ const unsigned long *mask,
+ u64 *stats, const void *dma_buf, bool accumulate)
+{
+ size_t index;
+
+ for_each_set_bit(index, mask, count) {
+ if (desc[index].dma_width) {
+ const void *addr = dma_buf + desc[index].offset;
+ u64 val;
+
+ switch (desc[index].dma_width) {
+ case 16:
+ val = le16_to_cpup((__le16 *)addr);
+ break;
+ case 32:
+ val = le32_to_cpup((__le32 *)addr);
+ break;
+ case 64:
+ val = le64_to_cpup((__le64 *)addr);
+ break;
+ default:
+ WARN_ON(1);
+ val = 0;
+ break;
+ }
+
+ if (accumulate)
+ stats[index] += val;
+ else
+ stats[index] = val;
+ }
+ }
+}
+
+void ef4_nic_fix_nodesc_drop_stat(struct ef4_nic *efx, u64 *rx_nodesc_drops)
+{
+ /* if down, or this is the first update after coming up */
+ if (!(efx->net_dev->flags & IFF_UP) || !efx->rx_nodesc_drops_prev_state)
+ efx->rx_nodesc_drops_while_down +=
+ *rx_nodesc_drops - efx->rx_nodesc_drops_total;
+ efx->rx_nodesc_drops_total = *rx_nodesc_drops;
+ efx->rx_nodesc_drops_prev_state = !!(efx->net_dev->flags & IFF_UP);
+ *rx_nodesc_drops -= efx->rx_nodesc_drops_while_down;
+}