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Release 4.14 arch/powerpc/platforms/pasemi/dma_lib.c

/*
 * Copyright (C) 2006-2007 PA Semi, Inc
 *
 * Common functions for DMA access on PA Semi PWRficient
 *
 * 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
 */

#include <linux/kernel.h>
#include <linux/export.h>
#include <linux/pci.h>
#include <linux/slab.h>
#include <linux/of.h>
#include <linux/sched.h>

#include <asm/pasemi_dma.h>


#define MAX_TXCH 64

#define MAX_RXCH 64

#define MAX_FLAGS 64

#define MAX_FUN 8


static struct pasdma_status *dma_status;


static void __iomem *iob_regs;

static void __iomem *mac_regs[6];

static void __iomem *dma_regs;


static int base_hw_irq;



static int num_txch, num_rxch;


static struct pci_dev *dma_pdev;

/* Bitmaps to handle allocation of channels */

static DECLARE_BITMAP(txch_free, MAX_TXCH);
static DECLARE_BITMAP(rxch_free, MAX_RXCH);
static DECLARE_BITMAP(flags_free, MAX_FLAGS);
static DECLARE_BITMAP(fun_free, MAX_FUN);

/* pasemi_read_iob_reg - read IOB register
 * @reg: Register to read (offset into PCI CFG space)
 */

unsigned int pasemi_read_iob_reg(unsigned int reg) { return in_le32(iob_regs+reg); }

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Olof Johansson18100.00%1100.00%
Total18100.00%1100.00%

EXPORT_SYMBOL(pasemi_read_iob_reg); /* pasemi_write_iob_reg - write IOB register * @reg: Register to write to (offset into PCI CFG space) * @val: Value to write */
void pasemi_write_iob_reg(unsigned int reg, unsigned int val) { out_le32(iob_regs+reg, val); }

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Olof Johansson22100.00%1100.00%
Total22100.00%1100.00%

EXPORT_SYMBOL(pasemi_write_iob_reg); /* pasemi_read_mac_reg - read MAC register * @intf: MAC interface * @reg: Register to read (offset into PCI CFG space) */
unsigned int pasemi_read_mac_reg(int intf, unsigned int reg) { return in_le32(mac_regs[intf]+reg); }

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Olof Johansson24100.00%1100.00%
Total24100.00%1100.00%

EXPORT_SYMBOL(pasemi_read_mac_reg); /* pasemi_write_mac_reg - write MAC register * @intf: MAC interface * @reg: Register to write to (offset into PCI CFG space) * @val: Value to write */
void pasemi_write_mac_reg(int intf, unsigned int reg, unsigned int val) { out_le32(mac_regs[intf]+reg, val); }

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Olof Johansson28100.00%1100.00%
Total28100.00%1100.00%

EXPORT_SYMBOL(pasemi_write_mac_reg); /* pasemi_read_dma_reg - read DMA register * @reg: Register to read (offset into PCI CFG space) */
unsigned int pasemi_read_dma_reg(unsigned int reg) { return in_le32(dma_regs+reg); }

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Olof Johansson18100.00%1100.00%
Total18100.00%1100.00%

EXPORT_SYMBOL(pasemi_read_dma_reg); /* pasemi_write_dma_reg - write DMA register * @reg: Register to write to (offset into PCI CFG space) * @val: Value to write */
void pasemi_write_dma_reg(unsigned int reg, unsigned int val) { out_le32(dma_regs+reg, val); }

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Olof Johansson22100.00%1100.00%
Total22100.00%1100.00%

EXPORT_SYMBOL(pasemi_write_dma_reg);
static int pasemi_alloc_tx_chan(enum pasemi_dmachan_type type) { int bit; int start, limit; switch (type & (TXCHAN_EVT0|TXCHAN_EVT1)) { case TXCHAN_EVT0: start = 0; limit = 10; break; case TXCHAN_EVT1: start = 10; limit = MAX_TXCH; break; default: start = 0; limit = MAX_TXCH; break; } retry: bit = find_next_bit(txch_free, MAX_TXCH, start); if (bit >= limit) return -ENOSPC; if (!test_and_clear_bit(bit, txch_free)) goto retry; return bit; }

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Olof Johansson103100.00%1100.00%
Total103100.00%1100.00%


static void pasemi_free_tx_chan(int chan) { BUG_ON(test_bit(chan, txch_free)); set_bit(chan, txch_free); }

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Olof Johansson26100.00%1100.00%
Total26100.00%1100.00%


static int pasemi_alloc_rx_chan(void) { int bit; retry: bit = find_first_bit(rxch_free, MAX_RXCH); if (bit >= MAX_TXCH) return -ENOSPC; if (!test_and_clear_bit(bit, rxch_free)) goto retry; return bit; }

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Olof Johansson48100.00%1100.00%
Total48100.00%1100.00%


static void pasemi_free_rx_chan(int chan) { BUG_ON(test_bit(chan, rxch_free)); set_bit(chan, rxch_free); }

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Olof Johansson26100.00%1100.00%
Total26100.00%1100.00%

/* pasemi_dma_alloc_chan - Allocate a DMA channel * @type: Type of channel to allocate * @total_size: Total size of structure to allocate (to allow for more * room behind the structure to be used by the client) * @offset: Offset in bytes from start of the total structure to the beginning * of struct pasemi_dmachan. Needed when struct pasemi_dmachan is * not the first member of the client structure. * * pasemi_dma_alloc_chan allocates a DMA channel for use by a client. The * type argument specifies whether it's a RX or TX channel, and in the case * of TX channels which group it needs to belong to (if any). * * Returns a pointer to the total structure allocated on success, NULL * on failure. */
void *pasemi_dma_alloc_chan(enum pasemi_dmachan_type type, int total_size, int offset) { void *buf; struct pasemi_dmachan *chan; int chno; BUG_ON(total_size < sizeof(struct pasemi_dmachan)); buf = kzalloc(total_size, GFP_KERNEL); if (!buf) return NULL; chan = buf + offset; chan->priv = buf; switch (type & (TXCHAN|RXCHAN)) { case RXCHAN: chno = pasemi_alloc_rx_chan(); chan->chno = chno; chan->irq = irq_create_mapping(NULL, base_hw_irq + num_txch + chno); chan->status = &dma_status->rx_sta[chno]; break; case TXCHAN: chno = pasemi_alloc_tx_chan(type); chan->chno = chno; chan->irq = irq_create_mapping(NULL, base_hw_irq + chno); chan->status = &dma_status->tx_sta[chno]; break; } chan->chan_type = type; return chan; }

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Olof Johansson173100.00%1100.00%
Total173100.00%1100.00%

EXPORT_SYMBOL(pasemi_dma_alloc_chan); /* pasemi_dma_free_chan - Free a previously allocated channel * @chan: Channel to free * * Frees a previously allocated channel. It will also deallocate any * descriptor ring associated with the channel, if allocated. */
void pasemi_dma_free_chan(struct pasemi_dmachan *chan) { if (chan->ring_virt) pasemi_dma_free_ring(chan); switch (chan->chan_type & (RXCHAN|TXCHAN)) { case RXCHAN: pasemi_free_rx_chan(chan->chno); break; case TXCHAN: pasemi_free_tx_chan(chan->chno); break; } kfree(chan->priv); }

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Olof Johansson64100.00%1100.00%
Total64100.00%1100.00%

EXPORT_SYMBOL(pasemi_dma_free_chan); /* pasemi_dma_alloc_ring - Allocate descriptor ring for a channel * @chan: Channel for which to allocate * @ring_size: Ring size in 64-bit (8-byte) words * * Allocate a descriptor ring for a channel. Returns 0 on success, errno * on failure. The passed in struct pasemi_dmachan is updated with the * virtual and DMA addresses of the ring. */
int pasemi_dma_alloc_ring(struct pasemi_dmachan *chan, int ring_size) { BUG_ON(chan->ring_virt); chan->ring_size = ring_size; chan->ring_virt = dma_alloc_coherent(&dma_pdev->dev, ring_size * sizeof(u64), &chan->ring_dma, GFP_KERNEL); if (!chan->ring_virt) return -ENOMEM; memset(chan->ring_virt, 0, ring_size * sizeof(u64)); return 0; }

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Olof Johansson82100.00%1100.00%
Total82100.00%1100.00%

EXPORT_SYMBOL(pasemi_dma_alloc_ring); /* pasemi_dma_free_ring - Free an allocated descriptor ring for a channel * @chan: Channel for which to free the descriptor ring * * Frees a previously allocated descriptor ring for a channel. */
void pasemi_dma_free_ring(struct pasemi_dmachan *chan) { BUG_ON(!chan->ring_virt); dma_free_coherent(&dma_pdev->dev, chan->ring_size * sizeof(u64), chan->ring_virt, chan->ring_dma); chan->ring_virt = NULL; chan->ring_size = 0; chan->ring_dma = 0; }

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Olof Johansson61100.00%1100.00%
Total61100.00%1100.00%

EXPORT_SYMBOL(pasemi_dma_free_ring); /* pasemi_dma_start_chan - Start a DMA channel * @chan: Channel to start * @cmdsta: Additional CCMDSTA/TCMDSTA bits to write * * Enables (starts) a DMA channel with optional additional arguments. */
void pasemi_dma_start_chan(const struct pasemi_dmachan *chan, const u32 cmdsta) { if (chan->chan_type == RXCHAN) pasemi_write_dma_reg(PAS_DMA_RXCHAN_CCMDSTA(chan->chno), cmdsta | PAS_DMA_RXCHAN_CCMDSTA_EN); else pasemi_write_dma_reg(PAS_DMA_TXCHAN_TCMDSTA(chan->chno), cmdsta | PAS_DMA_TXCHAN_TCMDSTA_EN); }

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Olof Johansson52100.00%1100.00%
Total52100.00%1100.00%

EXPORT_SYMBOL(pasemi_dma_start_chan); /* pasemi_dma_stop_chan - Stop a DMA channel * @chan: Channel to stop * * Stops (disables) a DMA channel. This is done by setting the ST bit in the * CMDSTA register and waiting on the ACT (active) bit to clear, then * finally disabling the whole channel. * * This function will only try for a short while for the channel to stop, if * it doesn't it will return failure. * * Returns 1 on success, 0 on failure. */ #define MAX_RETRIES 5000
int pasemi_dma_stop_chan(const struct pasemi_dmachan *chan) { int reg, retries; u32 sta; if (chan->chan_type == RXCHAN) { reg = PAS_DMA_RXCHAN_CCMDSTA(chan->chno); pasemi_write_dma_reg(reg, PAS_DMA_RXCHAN_CCMDSTA_ST); for (retries = 0; retries < MAX_RETRIES; retries++) { sta = pasemi_read_dma_reg(reg); if (!(sta & PAS_DMA_RXCHAN_CCMDSTA_ACT)) { pasemi_write_dma_reg(reg, 0); return 1; } cond_resched(); } } else { reg = PAS_DMA_TXCHAN_TCMDSTA(chan->chno); pasemi_write_dma_reg(reg, PAS_DMA_TXCHAN_TCMDSTA_ST); for (retries = 0; retries < MAX_RETRIES; retries++) { sta = pasemi_read_dma_reg(reg); if (!(sta & PAS_DMA_TXCHAN_TCMDSTA_ACT)) { pasemi_write_dma_reg(reg, 0); return 1; } cond_resched(); } } return 0; }

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Olof Johansson159100.00%1100.00%
Total159100.00%1100.00%

EXPORT_SYMBOL(pasemi_dma_stop_chan); /* pasemi_dma_alloc_buf - Allocate a buffer to use for DMA * @chan: Channel to allocate for * @size: Size of buffer in bytes * @handle: DMA handle * * Allocate a buffer to be used by the DMA engine for read/write, * similar to dma_alloc_coherent(). * * Returns the virtual address of the buffer, or NULL in case of failure. */
void *pasemi_dma_alloc_buf(struct pasemi_dmachan *chan, int size, dma_addr_t *handle) { return dma_alloc_coherent(&dma_pdev->dev, size, handle, GFP_KERNEL); }

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Olof Johansson33100.00%1100.00%
Total33100.00%1100.00%

EXPORT_SYMBOL(pasemi_dma_alloc_buf); /* pasemi_dma_free_buf - Free a buffer used for DMA * @chan: Channel the buffer was allocated for * @size: Size of buffer in bytes * @handle: DMA handle * * Frees a previously allocated buffer. */
void pasemi_dma_free_buf(struct pasemi_dmachan *chan, int size, dma_addr_t *handle) { dma_free_coherent(&dma_pdev->dev, size, handle, GFP_KERNEL); }

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Olof Johansson31100.00%1100.00%
Total31100.00%1100.00%

EXPORT_SYMBOL(pasemi_dma_free_buf); /* pasemi_dma_alloc_flag - Allocate a flag (event) for channel synchronization * * Allocates a flag for use with channel synchronization (event descriptors). * Returns allocated flag (0-63), < 0 on error. */
int pasemi_dma_alloc_flag(void) { int bit; retry: bit = find_next_bit(flags_free, MAX_FLAGS, 0); if (bit >= MAX_FLAGS) return -ENOSPC; if (!test_and_clear_bit(bit, flags_free)) goto retry; return bit; }

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Olof Johansson49100.00%1100.00%
Total49100.00%1100.00%

EXPORT_SYMBOL(pasemi_dma_alloc_flag); /* pasemi_dma_free_flag - Deallocates a flag (event) * @flag: Flag number to deallocate * * Frees up a flag so it can be reused for other purposes. */
void pasemi_dma_free_flag(int flag) { BUG_ON(test_bit(flag, flags_free)); BUG_ON(flag >= MAX_FLAGS); set_bit(flag, flags_free); }

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Olof Johansson32100.00%1100.00%
Total32100.00%1100.00%

EXPORT_SYMBOL(pasemi_dma_free_flag); /* pasemi_dma_set_flag - Sets a flag (event) to 1 * @flag: Flag number to set active * * Sets the flag provided to 1. */
void pasemi_dma_set_flag(int flag) { BUG_ON(flag >= MAX_FLAGS); if (flag < 32) pasemi_write_dma_reg(PAS_DMA_TXF_SFLG0, 1 << flag); else pasemi_write_dma_reg(PAS_DMA_TXF_SFLG1, 1 << flag); }

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Olof Johansson40100.00%1100.00%
Total40100.00%1100.00%

EXPORT_SYMBOL(pasemi_dma_set_flag); /* pasemi_dma_clear_flag - Sets a flag (event) to 0 * @flag: Flag number to set inactive * * Sets the flag provided to 0. */
void pasemi_dma_clear_flag(int flag) { BUG_ON(flag >= MAX_FLAGS); if (flag < 32) pasemi_write_dma_reg(PAS_DMA_TXF_CFLG0, 1 << flag); else pasemi_write_dma_reg(PAS_DMA_TXF_CFLG1, 1 << flag); }

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Olof Johansson40100.00%1100.00%
Total40100.00%1100.00%

EXPORT_SYMBOL(pasemi_dma_clear_flag); /* pasemi_dma_alloc_fun - Allocate a function engine * * Allocates a function engine to use for crypto/checksum offload * Returns allocated engine (0-8), < 0 on error. */
int pasemi_dma_alloc_fun(void) { int bit; retry: bit = find_next_bit(fun_free, MAX_FLAGS, 0); if (bit >= MAX_FLAGS) return -ENOSPC; if (!test_and_clear_bit(bit, fun_free)) goto retry; return bit; }

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Olof Johansson49100.00%1100.00%
Total49100.00%1100.00%

EXPORT_SYMBOL(pasemi_dma_alloc_fun); /* pasemi_dma_free_fun - Deallocates a function engine * @flag: Engine number to deallocate * * Frees up a function engine so it can be used for other purposes. */
void pasemi_dma_free_fun(int fun) { BUG_ON(test_bit(fun, fun_free)); BUG_ON(fun >= MAX_FLAGS); set_bit(fun, fun_free); }

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Olof Johansson32100.00%1100.00%
Total32100.00%1100.00%

EXPORT_SYMBOL(pasemi_dma_free_fun);
static void *map_onedev(struct pci_dev *p, int index) { struct device_node *dn; void __iomem *ret; dn = pci_device_to_OF_node(p); if (!dn) goto fallback; ret = of_iomap(dn, index); if (!ret) goto fallback; return ret; fallback: /* This is hardcoded and ugly, but we have some firmware versions * that don't provide the register space in the device tree. Luckily * they are at well-known locations so we can just do the math here. */ return ioremap(0xe0000000 + (p->devfn << 12), 0x2000); }

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Olof Johansson79100.00%1100.00%
Total79100.00%1100.00%

/* pasemi_dma_init - Initialize the PA Semi DMA library * * This function initializes the DMA library. It must be called before * any other function in the library. * * Returns 0 on success, errno on failure. */
int pasemi_dma_init(void) { static DEFINE_SPINLOCK(init_lock); struct pci_dev *iob_pdev; struct pci_dev *pdev; struct resource res; struct device_node *dn; int i, intf, err = 0; unsigned long timeout; u32 tmp; if (!machine_is(pasemi)) return -ENODEV; spin_lock(&init_lock); /* Make sure we haven't already initialized */ if (dma_pdev) goto out; iob_pdev = pci_get_device(PCI_VENDOR_ID_PASEMI, 0xa001, NULL); if (!iob_pdev) { BUG(); printk(KERN_WARNING "Can't find I/O Bridge\n"); err = -ENODEV; goto out; } iob_regs = map_onedev(iob_pdev, 0); dma_pdev = pci_get_device(PCI_VENDOR_ID_PASEMI, 0xa007, NULL); if (!dma_pdev) { BUG(); printk(KERN_WARNING "Can't find DMA controller\n"); err = -ENODEV; goto out; } dma_regs = map_onedev(dma_pdev, 0); base_hw_irq = virq_to_hw(dma_pdev->irq); pci_read_config_dword(dma_pdev, PAS_DMA_CAP_TXCH, &tmp); num_txch = (tmp & PAS_DMA_CAP_TXCH_TCHN_M) >> PAS_DMA_CAP_TXCH_TCHN_S; pci_read_config_dword(dma_pdev, PAS_DMA_CAP_RXCH, &tmp); num_rxch = (tmp & PAS_DMA_CAP_RXCH_RCHN_M) >> PAS_DMA_CAP_RXCH_RCHN_S; intf = 0; for (pdev = pci_get_device(PCI_VENDOR_ID_PASEMI, 0xa006, NULL); pdev; pdev = pci_get_device(PCI_VENDOR_ID_PASEMI, 0xa006, pdev)) mac_regs[intf++] = map_onedev(pdev, 0); pci_dev_put(pdev); for (pdev = pci_get_device(PCI_VENDOR_ID_PASEMI, 0xa005, NULL); pdev; pdev = pci_get_device(PCI_VENDOR_ID_PASEMI, 0xa005, pdev)) mac_regs[intf++] = map_onedev(pdev, 0); pci_dev_put(pdev); dn = pci_device_to_OF_node(iob_pdev); if (dn) err = of_address_to_resource(dn, 1, &res); if (!dn || err) { /* Fallback for old firmware */ res.start = 0xfd800000; res.end = res.start + 0x1000; } dma_status = __ioremap(res.start, resource_size(&res), 0); pci_dev_put(iob_pdev); for (i = 0; i < MAX_TXCH; i++) __set_bit(i, txch_free); for (i = 0; i < MAX_RXCH; i++) __set_bit(i, rxch_free); timeout = jiffies + HZ; pasemi_write_dma_reg(PAS_DMA_COM_RXCMD, 0); while (pasemi_read_dma_reg(PAS_DMA_COM_RXSTA) & 1) { if (time_after(jiffies, timeout)) { pr_warning("Warning: Could not disable RX section\n"); break; } } timeout = jiffies + HZ; pasemi_write_dma_reg(PAS_DMA_COM_TXCMD, 0); while (pasemi_read_dma_reg(PAS_DMA_COM_TXSTA) & 1) { if (time_after(jiffies, timeout)) { pr_warning("Warning: Could not disable TX section\n"); break; } } /* setup resource allocations for the different DMA sections */ tmp = pasemi_read_dma_reg(PAS_DMA_COM_CFG); pasemi_write_dma_reg(PAS_DMA_COM_CFG, tmp | 0x18000000); /* enable tx section */ pasemi_write_dma_reg(PAS_DMA_COM_TXCMD, PAS_DMA_COM_TXCMD_EN); /* enable rx section */ pasemi_write_dma_reg(PAS_DMA_COM_RXCMD, PAS_DMA_COM_RXCMD_EN); for (i = 0; i < MAX_FLAGS; i++) __set_bit(i, flags_free); for (i = 0; i < MAX_FUN; i++) __set_bit(i, fun_free); /* clear all status flags */ pasemi_write_dma_reg(PAS_DMA_TXF_CFLG0, 0xffffffff); pasemi_write_dma_reg(PAS_DMA_TXF_CFLG1, 0xffffffff); printk(KERN_INFO "PA Semi PWRficient DMA library initialized " "(%d tx, %d rx channels)\n", num_txch, num_rxch); out: spin_unlock(&init_lock); return err; }

Contributors

PersonTokensPropCommitsCommitProp
Olof Johansson59898.68%466.67%
Joe Perches40.66%116.67%
Julia Lawall40.66%116.67%
Total606100.00%6100.00%

EXPORT_SYMBOL(pasemi_dma_init);

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Olof Johansson214599.26%545.45%
Julia Lawall40.19%19.09%
Paul Gortmaker40.19%218.18%
Joe Perches40.19%19.09%
Tejun Heo30.14%19.09%
Lucas De Marchi10.05%19.09%
Total2161100.00%11100.00%
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