| /* |
| * 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. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write to the Free Software |
| * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA. |
| * |
| * Copyright (C) 2011 John Crispin <blogic@openwrt.org> |
| */ |
| |
| #include <linux/init.h> |
| #include <linux/platform_device.h> |
| #include <linux/io.h> |
| #include <linux/dma-mapping.h> |
| |
| #include <lantiq_soc.h> |
| #include <xway_dma.h> |
| |
| #define LTQ_DMA_CTRL 0x10 |
| #define LTQ_DMA_CPOLL 0x14 |
| #define LTQ_DMA_CS 0x18 |
| #define LTQ_DMA_CCTRL 0x1C |
| #define LTQ_DMA_CDBA 0x20 |
| #define LTQ_DMA_CDLEN 0x24 |
| #define LTQ_DMA_CIS 0x28 |
| #define LTQ_DMA_CIE 0x2C |
| #define LTQ_DMA_PS 0x40 |
| #define LTQ_DMA_PCTRL 0x44 |
| #define LTQ_DMA_IRNEN 0xf4 |
| |
| #define DMA_DESCPT BIT(3) /* descriptor complete irq */ |
| #define DMA_TX BIT(8) /* TX channel direction */ |
| #define DMA_CHAN_ON BIT(0) /* channel on / off bit */ |
| #define DMA_PDEN BIT(6) /* enable packet drop */ |
| #define DMA_CHAN_RST BIT(1) /* channel on / off bit */ |
| #define DMA_RESET BIT(0) /* channel on / off bit */ |
| #define DMA_IRQ_ACK 0x7e /* IRQ status register */ |
| #define DMA_POLL BIT(31) /* turn on channel polling */ |
| #define DMA_CLK_DIV4 BIT(6) /* polling clock divider */ |
| #define DMA_2W_BURST BIT(1) /* 2 word burst length */ |
| #define DMA_MAX_CHANNEL 20 /* the soc has 20 channels */ |
| #define DMA_ETOP_ENDIANESS (0xf << 8) /* endianess swap etop channels */ |
| #define DMA_WEIGHT (BIT(17) | BIT(16)) /* default channel wheight */ |
| |
| #define ltq_dma_r32(x) ltq_r32(ltq_dma_membase + (x)) |
| #define ltq_dma_w32(x, y) ltq_w32(x, ltq_dma_membase + (y)) |
| #define ltq_dma_w32_mask(x, y, z) ltq_w32_mask(x, y, \ |
| ltq_dma_membase + (z)) |
| |
| static struct resource ltq_dma_resource = { |
| .name = "dma", |
| .start = LTQ_DMA_BASE_ADDR, |
| .end = LTQ_DMA_BASE_ADDR + LTQ_DMA_SIZE - 1, |
| .flags = IORESOURCE_MEM, |
| }; |
| |
| static void __iomem *ltq_dma_membase; |
| |
| void |
| ltq_dma_enable_irq(struct ltq_dma_channel *ch) |
| { |
| unsigned long flags; |
| |
| local_irq_save(flags); |
| ltq_dma_w32(ch->nr, LTQ_DMA_CS); |
| ltq_dma_w32_mask(0, 1 << ch->nr, LTQ_DMA_IRNEN); |
| local_irq_restore(flags); |
| } |
| EXPORT_SYMBOL_GPL(ltq_dma_enable_irq); |
| |
| void |
| ltq_dma_disable_irq(struct ltq_dma_channel *ch) |
| { |
| unsigned long flags; |
| |
| local_irq_save(flags); |
| ltq_dma_w32(ch->nr, LTQ_DMA_CS); |
| ltq_dma_w32_mask(1 << ch->nr, 0, LTQ_DMA_IRNEN); |
| local_irq_restore(flags); |
| } |
| EXPORT_SYMBOL_GPL(ltq_dma_disable_irq); |
| |
| void |
| ltq_dma_ack_irq(struct ltq_dma_channel *ch) |
| { |
| unsigned long flags; |
| |
| local_irq_save(flags); |
| ltq_dma_w32(ch->nr, LTQ_DMA_CS); |
| ltq_dma_w32(DMA_IRQ_ACK, LTQ_DMA_CIS); |
| local_irq_restore(flags); |
| } |
| EXPORT_SYMBOL_GPL(ltq_dma_ack_irq); |
| |
| void |
| ltq_dma_open(struct ltq_dma_channel *ch) |
| { |
| unsigned long flag; |
| |
| local_irq_save(flag); |
| ltq_dma_w32(ch->nr, LTQ_DMA_CS); |
| ltq_dma_w32_mask(0, DMA_CHAN_ON, LTQ_DMA_CCTRL); |
| ltq_dma_enable_irq(ch); |
| local_irq_restore(flag); |
| } |
| EXPORT_SYMBOL_GPL(ltq_dma_open); |
| |
| void |
| ltq_dma_close(struct ltq_dma_channel *ch) |
| { |
| unsigned long flag; |
| |
| local_irq_save(flag); |
| ltq_dma_w32(ch->nr, LTQ_DMA_CS); |
| ltq_dma_w32_mask(DMA_CHAN_ON, 0, LTQ_DMA_CCTRL); |
| ltq_dma_disable_irq(ch); |
| local_irq_restore(flag); |
| } |
| EXPORT_SYMBOL_GPL(ltq_dma_close); |
| |
| static void |
| ltq_dma_alloc(struct ltq_dma_channel *ch) |
| { |
| unsigned long flags; |
| |
| ch->desc = 0; |
| ch->desc_base = dma_alloc_coherent(NULL, |
| LTQ_DESC_NUM * LTQ_DESC_SIZE, |
| &ch->phys, GFP_ATOMIC); |
| memset(ch->desc_base, 0, LTQ_DESC_NUM * LTQ_DESC_SIZE); |
| |
| local_irq_save(flags); |
| ltq_dma_w32(ch->nr, LTQ_DMA_CS); |
| ltq_dma_w32(ch->phys, LTQ_DMA_CDBA); |
| ltq_dma_w32(LTQ_DESC_NUM, LTQ_DMA_CDLEN); |
| ltq_dma_w32_mask(DMA_CHAN_ON, 0, LTQ_DMA_CCTRL); |
| wmb(); |
| ltq_dma_w32_mask(0, DMA_CHAN_RST, LTQ_DMA_CCTRL); |
| while (ltq_dma_r32(LTQ_DMA_CCTRL) & DMA_CHAN_RST) |
| ; |
| local_irq_restore(flags); |
| } |
| |
| void |
| ltq_dma_alloc_tx(struct ltq_dma_channel *ch) |
| { |
| unsigned long flags; |
| |
| ltq_dma_alloc(ch); |
| |
| local_irq_save(flags); |
| ltq_dma_w32(DMA_DESCPT, LTQ_DMA_CIE); |
| ltq_dma_w32_mask(0, 1 << ch->nr, LTQ_DMA_IRNEN); |
| ltq_dma_w32(DMA_WEIGHT | DMA_TX, LTQ_DMA_CCTRL); |
| local_irq_restore(flags); |
| } |
| EXPORT_SYMBOL_GPL(ltq_dma_alloc_tx); |
| |
| void |
| ltq_dma_alloc_rx(struct ltq_dma_channel *ch) |
| { |
| unsigned long flags; |
| |
| ltq_dma_alloc(ch); |
| |
| local_irq_save(flags); |
| ltq_dma_w32(DMA_DESCPT, LTQ_DMA_CIE); |
| ltq_dma_w32_mask(0, 1 << ch->nr, LTQ_DMA_IRNEN); |
| ltq_dma_w32(DMA_WEIGHT, LTQ_DMA_CCTRL); |
| local_irq_restore(flags); |
| } |
| EXPORT_SYMBOL_GPL(ltq_dma_alloc_rx); |
| |
| void |
| ltq_dma_free(struct ltq_dma_channel *ch) |
| { |
| if (!ch->desc_base) |
| return; |
| ltq_dma_close(ch); |
| dma_free_coherent(NULL, LTQ_DESC_NUM * LTQ_DESC_SIZE, |
| ch->desc_base, ch->phys); |
| } |
| EXPORT_SYMBOL_GPL(ltq_dma_free); |
| |
| void |
| ltq_dma_init_port(int p) |
| { |
| ltq_dma_w32(p, LTQ_DMA_PS); |
| switch (p) { |
| case DMA_PORT_ETOP: |
| /* |
| * Tell the DMA engine to swap the endianess of data frames and |
| * drop packets if the channel arbitration fails. |
| */ |
| ltq_dma_w32_mask(0, DMA_ETOP_ENDIANESS | DMA_PDEN, |
| LTQ_DMA_PCTRL); |
| break; |
| |
| case DMA_PORT_DEU: |
| ltq_dma_w32((DMA_2W_BURST << 4) | (DMA_2W_BURST << 2), |
| LTQ_DMA_PCTRL); |
| break; |
| |
| default: |
| break; |
| } |
| } |
| EXPORT_SYMBOL_GPL(ltq_dma_init_port); |
| |
| int __init |
| ltq_dma_init(void) |
| { |
| int i; |
| |
| /* insert and request the memory region */ |
| if (insert_resource(&iomem_resource, <q_dma_resource) < 0) |
| panic("Failed to insert dma memory\n"); |
| |
| if (request_mem_region(ltq_dma_resource.start, |
| resource_size(<q_dma_resource), "dma") < 0) |
| panic("Failed to request dma memory\n"); |
| |
| /* remap dma register range */ |
| ltq_dma_membase = ioremap_nocache(ltq_dma_resource.start, |
| resource_size(<q_dma_resource)); |
| if (!ltq_dma_membase) |
| panic("Failed to remap dma memory\n"); |
| |
| /* power up and reset the dma engine */ |
| ltq_pmu_enable(PMU_DMA); |
| ltq_dma_w32_mask(0, DMA_RESET, LTQ_DMA_CTRL); |
| |
| /* disable all interrupts */ |
| ltq_dma_w32(0, LTQ_DMA_IRNEN); |
| |
| /* reset/configure each channel */ |
| for (i = 0; i < DMA_MAX_CHANNEL; i++) { |
| ltq_dma_w32(i, LTQ_DMA_CS); |
| ltq_dma_w32(DMA_CHAN_RST, LTQ_DMA_CCTRL); |
| ltq_dma_w32(DMA_POLL | DMA_CLK_DIV4, LTQ_DMA_CPOLL); |
| ltq_dma_w32_mask(DMA_CHAN_ON, 0, LTQ_DMA_CCTRL); |
| } |
| return 0; |
| } |
| |
| postcore_initcall(ltq_dma_init); |