kernel/drivers/net/ethernet/samsung/sxgbe/sxgbe_dma.c

   1 /* 10G controller driver for Samsung SoCs
   2  *
   3  * Copyright (C) 2013 Samsung Electronics Co., Ltd.
   4  *              http://www.samsung.com
   5  *
   6  * Author: Siva Reddy Kallam <siva.kallam@samsung.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  */
  12 #include <linux/delay.h>
  13 #include <linux/export.h>
  14 #include <linux/io.h>
  15 #include <linux/netdevice.h>
  16 #include <linux/phy.h>
  17
  18 #include "sxgbe_common.h"
  19 #include "sxgbe_dma.h"
  20 #include "sxgbe_reg.h"
  21 #include "sxgbe_desc.h"
  22
  23 /* DMA core initialization */
  24 static int sxgbe_dma_init(void __iomem *ioaddr, int fix_burst, int burst_map)
  25 {
  26         u32 reg_val;
  27
  28         reg_val = readl(ioaddr + SXGBE_DMA_SYSBUS_MODE_REG);
  29
  30         /* if fix_burst = 0, Set UNDEF = 1 of DMA_Sys_Mode Register.
  31          * if fix_burst = 1, Set UNDEF = 0 of DMA_Sys_Mode Register.
  32          * burst_map is bitmap for  BLEN[4, 8, 16, 32, 64, 128 and 256].
  33          * Set burst_map irrespective of fix_burst value.
  34          */
  35         if (!fix_burst)
  36                 reg_val |= SXGBE_DMA_AXI_UNDEF_BURST;
  37
  38         /* write burst len map */
  39         reg_val |= (burst_map << SXGBE_DMA_BLENMAP_LSHIFT);
  40
  41         writel(reg_val, ioaddr + SXGBE_DMA_SYSBUS_MODE_REG);
  42
  43         return 0;
  44 }
  45
  46 static void sxgbe_dma_channel_init(void __iomem *ioaddr, int cha_num,
  47                                    int fix_burst, int pbl, dma_addr_t dma_tx,
  48                                    dma_addr_t dma_rx, int t_rsize, int r_rsize)
  49 {
  50         u32 reg_val;
  51         dma_addr_t dma_addr;
  52
  53         reg_val = readl(ioaddr + SXGBE_DMA_CHA_CTL_REG(cha_num));
  54         /* set the pbl */
  55         if (fix_burst) {
  56                 reg_val |= SXGBE_DMA_PBL_X8MODE;
  57                 writel(reg_val, ioaddr + SXGBE_DMA_CHA_CTL_REG(cha_num));
  58                 /* program the TX pbl */
  59                 reg_val = readl(ioaddr + SXGBE_DMA_CHA_TXCTL_REG(cha_num));
  60                 reg_val |= (pbl << SXGBE_DMA_TXPBL_LSHIFT);
  61                 writel(reg_val, ioaddr + SXGBE_DMA_CHA_TXCTL_REG(cha_num));
  62                 /* program the RX pbl */
  63                 reg_val = readl(ioaddr + SXGBE_DMA_CHA_RXCTL_REG(cha_num));
  64                 reg_val |= (pbl << SXGBE_DMA_RXPBL_LSHIFT);
  65                 writel(reg_val, ioaddr + SXGBE_DMA_CHA_RXCTL_REG(cha_num));
  66         }
  67
  68         /* program desc registers */
  69         writel(upper_32_bits(dma_tx),
  70                ioaddr + SXGBE_DMA_CHA_TXDESC_HADD_REG(cha_num));
  71         writel(lower_32_bits(dma_tx),
  72                ioaddr + SXGBE_DMA_CHA_TXDESC_LADD_REG(cha_num));
  73
  74         writel(upper_32_bits(dma_rx),
  75                ioaddr + SXGBE_DMA_CHA_RXDESC_HADD_REG(cha_num));
  76         writel(lower_32_bits(dma_rx),
  77                ioaddr + SXGBE_DMA_CHA_RXDESC_LADD_REG(cha_num));
  78
  79         /* program tail pointers */
  80         /* assumption: upper 32 bits are constant and
  81          * same as TX/RX desc list
  82          */
  83         dma_addr = dma_tx + ((t_rsize - 1) * SXGBE_DESC_SIZE_BYTES);
  84         writel(lower_32_bits(dma_addr),
  85                ioaddr + SXGBE_DMA_CHA_TXDESC_TAILPTR_REG(cha_num));
  86
  87         dma_addr = dma_rx + ((r_rsize - 1) * SXGBE_DESC_SIZE_BYTES);
  88         writel(lower_32_bits(dma_addr),
  89                ioaddr + SXGBE_DMA_CHA_RXDESC_LADD_REG(cha_num));
  90         /* program the ring sizes */
  91         writel(t_rsize - 1, ioaddr + SXGBE_DMA_CHA_TXDESC_RINGLEN_REG(cha_num));
  92         writel(r_rsize - 1, ioaddr + SXGBE_DMA_CHA_RXDESC_RINGLEN_REG(cha_num));
  93
  94         /* Enable TX/RX interrupts */
  95         writel(SXGBE_DMA_ENA_INT,
  96                ioaddr + SXGBE_DMA_CHA_INT_ENABLE_REG(cha_num));
  97 }
  98
  99 static void sxgbe_enable_dma_transmission(void __iomem *ioaddr, int cha_num)
 100 {
 101         u32 tx_config;
 102
 103         tx_config = readl(ioaddr + SXGBE_DMA_CHA_TXCTL_REG(cha_num));
 104         tx_config |= SXGBE_TX_START_DMA;
 105         writel(tx_config, ioaddr + SXGBE_DMA_CHA_TXCTL_REG(cha_num));
 106 }
 107
 108 static void sxgbe_enable_dma_irq(void __iomem *ioaddr, int dma_cnum)
 109 {
 110         /* Enable TX/RX interrupts */
 111         writel(SXGBE_DMA_ENA_INT,
 112                ioaddr + SXGBE_DMA_CHA_INT_ENABLE_REG(dma_cnum));
 113 }
 114
 115 static void sxgbe_disable_dma_irq(void __iomem *ioaddr, int dma_cnum)
 116 {
 117         /* Disable TX/RX interrupts */
 118         writel(0, ioaddr + SXGBE_DMA_CHA_INT_ENABLE_REG(dma_cnum));
 119 }
 120
 121 static void sxgbe_dma_start_tx(void __iomem *ioaddr, int tchannels)
 122 {
 123         int cnum;
 124         u32 tx_ctl_reg;
 125
 126         for (cnum = 0; cnum < tchannels; cnum++) {
 127                 tx_ctl_reg = readl(ioaddr + SXGBE_DMA_CHA_TXCTL_REG(cnum));
 128                 tx_ctl_reg |= SXGBE_TX_ENABLE;
 129                 writel(tx_ctl_reg,
 130                        ioaddr + SXGBE_DMA_CHA_TXCTL_REG(cnum));
 131         }
 132 }
 133
 134 static void sxgbe_dma_start_tx_queue(void __iomem *ioaddr, int dma_cnum)
 135 {
 136         u32 tx_ctl_reg;
 137
 138         tx_ctl_reg = readl(ioaddr + SXGBE_DMA_CHA_TXCTL_REG(dma_cnum));
 139         tx_ctl_reg |= SXGBE_TX_ENABLE;
 140         writel(tx_ctl_reg, ioaddr + SXGBE_DMA_CHA_TXCTL_REG(dma_cnum));
 141 }
 142
 143 static void sxgbe_dma_stop_tx_queue(void __iomem *ioaddr, int dma_cnum)
 144 {
 145         u32 tx_ctl_reg;
 146
 147         tx_ctl_reg = readl(ioaddr + SXGBE_DMA_CHA_TXCTL_REG(dma_cnum));
 148         tx_ctl_reg &= ~(SXGBE_TX_ENABLE);
 149         writel(tx_ctl_reg, ioaddr + SXGBE_DMA_CHA_TXCTL_REG(dma_cnum));
 150 }
 151
 152 static void sxgbe_dma_stop_tx(void __iomem *ioaddr, int tchannels)
 153 {
 154         int cnum;
 155         u32 tx_ctl_reg;
 156
 157         for (cnum = 0; cnum < tchannels; cnum++) {
 158                 tx_ctl_reg = readl(ioaddr + SXGBE_DMA_CHA_TXCTL_REG(cnum));
 159                 tx_ctl_reg &= ~(SXGBE_TX_ENABLE);
 160                 writel(tx_ctl_reg, ioaddr + SXGBE_DMA_CHA_TXCTL_REG(cnum));
 161         }
 162 }
 163
 164 static void sxgbe_dma_start_rx(void __iomem *ioaddr, int rchannels)
 165 {
 166         int cnum;
 167         u32 rx_ctl_reg;
 168
 169         for (cnum = 0; cnum < rchannels; cnum++) {
 170                 rx_ctl_reg = readl(ioaddr + SXGBE_DMA_CHA_RXCTL_REG(cnum));
 171                 rx_ctl_reg |= SXGBE_RX_ENABLE;
 172                 writel(rx_ctl_reg,
 173                        ioaddr + SXGBE_DMA_CHA_RXCTL_REG(cnum));
 174         }
 175 }
 176
 177 static void sxgbe_dma_stop_rx(void __iomem *ioaddr, int rchannels)
 178 {
 179         int cnum;
 180         u32 rx_ctl_reg;
 181
 182         for (cnum = 0; cnum < rchannels; cnum++) {
 183                 rx_ctl_reg = readl(ioaddr + SXGBE_DMA_CHA_RXCTL_REG(cnum));
 184                 rx_ctl_reg &= ~(SXGBE_RX_ENABLE);
 185                 writel(rx_ctl_reg, ioaddr + SXGBE_DMA_CHA_RXCTL_REG(cnum));
 186         }
 187 }
 188
 189 static int sxgbe_tx_dma_int_status(void __iomem *ioaddr, int channel_no,
 190                                    struct sxgbe_extra_stats *x)
 191 {
 192         u32 int_status = readl(ioaddr + SXGBE_DMA_CHA_STATUS_REG(channel_no));
 193         u32 clear_val = 0;
 194         u32 ret_val = 0;
 195
 196         /* TX Normal Interrupt Summary */
 197         if (likely(int_status & SXGBE_DMA_INT_STATUS_NIS)) {
 198                 x->normal_irq_n++;
 199                 if (int_status & SXGBE_DMA_INT_STATUS_TI) {
 200                         ret_val |= handle_tx;
 201                         x->tx_normal_irq_n++;
 202                         clear_val |= SXGBE_DMA_INT_STATUS_TI;
 203                 }
 204
 205                 if (int_status & SXGBE_DMA_INT_STATUS_TBU) {
 206                         x->tx_underflow_irq++;
 207                         ret_val |= tx_bump_tc;
 208                         clear_val |= SXGBE_DMA_INT_STATUS_TBU;
 209                 }
 210         } else if (unlikely(int_status & SXGBE_DMA_INT_STATUS_AIS)) {
 211                 /* TX Abnormal Interrupt Summary */
 212                 if (int_status & SXGBE_DMA_INT_STATUS_TPS) {
 213                         ret_val |= tx_hard_error;
 214                         clear_val |= SXGBE_DMA_INT_STATUS_TPS;
 215                         x->tx_process_stopped_irq++;
 216                 }
 217
 218                 if (int_status & SXGBE_DMA_INT_STATUS_FBE) {
 219                         ret_val |= tx_hard_error;
 220                         x->fatal_bus_error_irq++;
 221
 222                         /* Assumption: FBE bit is the combination of
 223                          * all the bus access erros and cleared when
 224                          * the respective error bits cleared
 225                          */
 226
 227                         /* check for actual cause */
 228                         if (int_status & SXGBE_DMA_INT_STATUS_TEB0) {
 229                                 x->tx_read_transfer_err++;
 230                                 clear_val |= SXGBE_DMA_INT_STATUS_TEB0;
 231                         } else {
 232                                 x->tx_write_transfer_err++;
 233                         }
 234
 235                         if (int_status & SXGBE_DMA_INT_STATUS_TEB1) {
 236                                 x->tx_desc_access_err++;
 237                                 clear_val |= SXGBE_DMA_INT_STATUS_TEB1;
 238                         } else {
 239                                 x->tx_buffer_access_err++;
 240                         }
 241
 242                         if (int_status & SXGBE_DMA_INT_STATUS_TEB2) {
 243                                 x->tx_data_transfer_err++;
 244                                 clear_val |= SXGBE_DMA_INT_STATUS_TEB2;
 245                         }
 246                 }
 247
 248                 /* context descriptor error */
 249                 if (int_status & SXGBE_DMA_INT_STATUS_CTXTERR) {
 250                         x->tx_ctxt_desc_err++;
 251                         clear_val |= SXGBE_DMA_INT_STATUS_CTXTERR;
 252                 }
 253         }
 254
 255         /* clear the served bits */
 256         writel(clear_val, ioaddr + SXGBE_DMA_CHA_STATUS_REG(channel_no));
 257
 258         return ret_val;
 259 }
 260
 261 static int sxgbe_rx_dma_int_status(void __iomem *ioaddr, int channel_no,
 262                                    struct sxgbe_extra_stats *x)
 263 {
 264         u32 int_status = readl(ioaddr + SXGBE_DMA_CHA_STATUS_REG(channel_no));
 265         u32 clear_val = 0;
 266         u32 ret_val = 0;
 267
 268         /* RX Normal Interrupt Summary */
 269         if (likely(int_status & SXGBE_DMA_INT_STATUS_NIS)) {
 270                 x->normal_irq_n++;
 271                 if (int_status & SXGBE_DMA_INT_STATUS_RI) {
 272                         ret_val |= handle_rx;
 273                         x->rx_normal_irq_n++;
 274                         clear_val |= SXGBE_DMA_INT_STATUS_RI;
 275                 }
 276         } else if (unlikely(int_status & SXGBE_DMA_INT_STATUS_AIS)) {
 277                 /* RX Abnormal Interrupt Summary */
 278                 if (int_status & SXGBE_DMA_INT_STATUS_RBU) {
 279                         ret_val |= rx_bump_tc;
 280                         clear_val |= SXGBE_DMA_INT_STATUS_RBU;
 281                         x->rx_underflow_irq++;
 282                 }
 283
 284                 if (int_status & SXGBE_DMA_INT_STATUS_RPS) {
 285                         ret_val |= rx_hard_error;
 286                         clear_val |= SXGBE_DMA_INT_STATUS_RPS;
 287                         x->rx_process_stopped_irq++;
 288                 }
 289
 290                 if (int_status & SXGBE_DMA_INT_STATUS_FBE) {
 291                         ret_val |= rx_hard_error;
 292                         x->fatal_bus_error_irq++;
 293
 294                         /* Assumption: FBE bit is the combination of
 295                          * all the bus access erros and cleared when
 296                          * the respective error bits cleared
 297                          */
 298
 299                         /* check for actual cause */
 300                         if (int_status & SXGBE_DMA_INT_STATUS_REB0) {
 301                                 x->rx_read_transfer_err++;
 302                                 clear_val |= SXGBE_DMA_INT_STATUS_REB0;
 303                         } else {
 304                                 x->rx_write_transfer_err++;
 305                         }
 306
 307                         if (int_status & SXGBE_DMA_INT_STATUS_REB1) {
 308                                 x->rx_desc_access_err++;
 309                                 clear_val |= SXGBE_DMA_INT_STATUS_REB1;
 310                         } else {
 311                                 x->rx_buffer_access_err++;
 312                         }
 313
 314                         if (int_status & SXGBE_DMA_INT_STATUS_REB2) {
 315                                 x->rx_data_transfer_err++;
 316                                 clear_val |= SXGBE_DMA_INT_STATUS_REB2;
 317                         }
 318                 }
 319         }
 320
 321         /* clear the served bits */
 322         writel(clear_val, ioaddr + SXGBE_DMA_CHA_STATUS_REG(channel_no));
 323
 324         return ret_val;
 325 }
 326
 327 /* Program the HW RX Watchdog */
 328 static void sxgbe_dma_rx_watchdog(void __iomem *ioaddr, u32 riwt)
 329 {
 330         u32 que_num;
 331
 332         SXGBE_FOR_EACH_QUEUE(SXGBE_RX_QUEUES, que_num) {
 333                 writel(riwt,
 334                        ioaddr + SXGBE_DMA_CHA_INT_RXWATCHTMR_REG(que_num));
 335         }
 336 }
 337
 338 static void sxgbe_enable_tso(void __iomem *ioaddr, u8 chan_num)
 339 {
 340         u32 ctrl;
 341
 342         ctrl = readl(ioaddr + SXGBE_DMA_CHA_TXCTL_REG(chan_num));
 343         ctrl |= SXGBE_DMA_CHA_TXCTL_TSE_ENABLE;
 344         writel(ctrl, ioaddr + SXGBE_DMA_CHA_TXCTL_REG(chan_num));
 345 }
 346
 347 static const struct sxgbe_dma_ops sxgbe_dma_ops = {
 348         .init                           = sxgbe_dma_init,
 349         .cha_init                       = sxgbe_dma_channel_init,
 350         .enable_dma_transmission        = sxgbe_enable_dma_transmission,
 351         .enable_dma_irq                 = sxgbe_enable_dma_irq,
 352         .disable_dma_irq                = sxgbe_disable_dma_irq,
 353         .start_tx                       = sxgbe_dma_start_tx,
 354         .start_tx_queue                 = sxgbe_dma_start_tx_queue,
 355         .stop_tx                        = sxgbe_dma_stop_tx,
 356         .stop_tx_queue                  = sxgbe_dma_stop_tx_queue,
 357         .start_rx                       = sxgbe_dma_start_rx,
 358         .stop_rx                        = sxgbe_dma_stop_rx,
 359         .tx_dma_int_status              = sxgbe_tx_dma_int_status,
 360         .rx_dma_int_status              = sxgbe_rx_dma_int_status,
 361         .rx_watchdog                    = sxgbe_dma_rx_watchdog,
 362         .enable_tso                     = sxgbe_enable_tso,
 363 };
 364
 365 const struct sxgbe_dma_ops *sxgbe_get_dma_ops(void)
 366 {
 367         return &sxgbe_dma_ops;
 368 }