From 8ee9d85779356c1dc2ba87aca27fbf9414f2d82b Mon Sep 17 00:00:00 2001 From: Olof Johansson Date: Wed, 28 Nov 2007 20:56:20 -0600 Subject: pasemi: DMA engine management library pasemi: DMA engine management library Introduce a DMA management library to manage the various DMA resources on the PA Semi SoCs. Since several drivers need to allocate these shared resources, provide some abstractions as well as allocation/free functions for channels, etc. Signed-off-by: Olof Johansson Signed-off-by: Jeff Garzik --- arch/powerpc/platforms/pasemi/Makefile | 2 +- arch/powerpc/platforms/pasemi/dma_lib.c | 487 ++++++++++++++++++++++++++++++++ arch/powerpc/platforms/pasemi/pasemi.h | 1 + include/asm-powerpc/pasemi_dma.h | 76 +++++ 4 files changed, 565 insertions(+), 1 deletion(-) create mode 100644 arch/powerpc/platforms/pasemi/dma_lib.c diff --git a/arch/powerpc/platforms/pasemi/Makefile b/arch/powerpc/platforms/pasemi/Makefile index f47fcac7e581..e636daa7a80e 100644 --- a/arch/powerpc/platforms/pasemi/Makefile +++ b/arch/powerpc/platforms/pasemi/Makefile @@ -1,4 +1,4 @@ -obj-y += setup.o pci.o time.o idle.o powersave.o iommu.o +obj-y += setup.o pci.o time.o idle.o powersave.o iommu.o dma_lib.o obj-$(CONFIG_PPC_PASEMI_MDIO) += gpio_mdio.o obj-$(CONFIG_ELECTRA_IDE) += electra_ide.o obj-$(CONFIG_PPC_PASEMI_CPUFREQ) += cpufreq.o diff --git a/arch/powerpc/platforms/pasemi/dma_lib.c b/arch/powerpc/platforms/pasemi/dma_lib.c new file mode 100644 index 000000000000..e6e474247dc9 --- /dev/null +++ b/arch/powerpc/platforms/pasemi/dma_lib.c @@ -0,0 +1,487 @@ +/* + * 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 +#include +#include +#include + +#include + +#define MAX_TXCH 64 +#define MAX_RXCH 64 + +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); + +/* 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); +} +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); +} +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); +} +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); +} +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); +} +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); +} +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; +} + +static void pasemi_free_tx_chan(int chan) +{ + BUG_ON(test_bit(chan, txch_free)); + set_bit(chan, txch_free); +} + +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; +} + +static void pasemi_free_rx_chan(int chan) +{ + BUG_ON(test_bit(chan, rxch_free)); + set_bit(chan, rxch_free); +} + +/* 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; +} +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); +} +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; +} +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; +} +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); +} +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; +} +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); +} +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); +} +EXPORT_SYMBOL(pasemi_dma_free_buf); + +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); +} + +/* 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 spinlock_t init_lock = SPIN_LOCK_UNLOCKED; + struct pci_dev *iob_pdev; + struct pci_dev *pdev; + struct resource res; + struct device_node *dn; + int i, intf, err = 0; + 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, res.end-res.start, 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); + + 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; +} diff --git a/arch/powerpc/platforms/pasemi/pasemi.h b/arch/powerpc/platforms/pasemi/pasemi.h index 516acabb4e96..58b344c6fc38 100644 --- a/arch/powerpc/platforms/pasemi/pasemi.h +++ b/arch/powerpc/platforms/pasemi/pasemi.h @@ -9,6 +9,7 @@ extern void __devinit pas_pci_dma_dev_setup(struct pci_dev *dev); extern void __iomem *pasemi_pci_getcfgaddr(struct pci_dev *dev, int offset); extern void __init alloc_iobmap_l2(void); +extern void __init pasemi_map_registers(void); /* Power savings modes, implemented in asm */ extern void idle_spin(void); diff --git a/include/asm-powerpc/pasemi_dma.h b/include/asm-powerpc/pasemi_dma.h index 8ef80d8bdecd..b4526ff3a50d 100644 --- a/include/asm-powerpc/pasemi_dma.h +++ b/include/asm-powerpc/pasemi_dma.h @@ -33,11 +33,27 @@ struct pasdma_status { * device. Use the normal PCI config access functions for them. */ enum { + PAS_DMA_CAP_TXCH = 0x44, /* Transmit Channel Info */ + PAS_DMA_CAP_RXCH = 0x48, /* Transmit Channel Info */ + PAS_DMA_CAP_IFI = 0x4c, /* Interface Info */ PAS_DMA_COM_TXCMD = 0x100, /* Transmit Command Register */ PAS_DMA_COM_TXSTA = 0x104, /* Transmit Status Register */ PAS_DMA_COM_RXCMD = 0x108, /* Receive Command Register */ PAS_DMA_COM_RXSTA = 0x10c, /* Receive Status Register */ }; + + +#define PAS_DMA_CAP_TXCH_TCHN_M 0x00ff0000 /* # of TX channels */ +#define PAS_DMA_CAP_TXCH_TCHN_S 16 + +#define PAS_DMA_CAP_RXCH_RCHN_M 0x00ff0000 /* # of RX channels */ +#define PAS_DMA_CAP_RXCH_RCHN_S 16 + +#define PAS_DMA_CAP_IFI_IOFF_M 0xff000000 /* Cfg reg for intf pointers */ +#define PAS_DMA_CAP_IFI_IOFF_S 24 +#define PAS_DMA_CAP_IFI_NIN_M 0x00ff0000 /* # of interfaces */ +#define PAS_DMA_CAP_IFI_NIN_S 16 + #define PAS_DMA_COM_TXCMD_EN 0x00000001 /* enable */ #define PAS_DMA_COM_TXSTA_ACT 0x00000001 /* active */ #define PAS_DMA_COM_RXCMD_EN 0x00000001 /* enable */ @@ -388,4 +404,64 @@ enum { CTRL_CMD_REG_M) + +/* Prototypes for the shared DMA functions in the platform code. */ + +/* DMA TX Channel type. Right now only limitations used are event types 0/1, + * for event-triggered DMA transactions. + */ + +enum pasemi_dmachan_type { + RXCHAN = 0, /* Any RX chan */ + TXCHAN = 1, /* Any TX chan */ + TXCHAN_EVT0 = 0x1001, /* TX chan in event class 0 (chan 0-9) */ + TXCHAN_EVT1 = 0x2001, /* TX chan in event class 1 (chan 10-19) */ +}; + +struct pasemi_dmachan { + int chno; /* Channel number */ + enum pasemi_dmachan_type chan_type; /* TX / RX */ + u64 *status; /* Ptr to cacheable status */ + int irq; /* IRQ used by channel */ + unsigned int ring_size; /* size of allocated ring */ + dma_addr_t ring_dma; /* DMA address for ring */ + u64 *ring_virt; /* Virt address for ring */ + void *priv; /* Ptr to start of client struct */ +}; + +/* Read/write the different registers in the I/O Bridge, Ethernet + * and DMA Controller + */ +extern unsigned int pasemi_read_iob_reg(unsigned int reg); +extern void pasemi_write_iob_reg(unsigned int reg, unsigned int val); + +extern unsigned int pasemi_read_mac_reg(int intf, unsigned int reg); +extern void pasemi_write_mac_reg(int intf, unsigned int reg, unsigned int val); + +extern unsigned int pasemi_read_dma_reg(unsigned int reg); +extern void pasemi_write_dma_reg(unsigned int reg, unsigned int val); + +/* Channel management routines */ + +extern void *pasemi_dma_alloc_chan(enum pasemi_dmachan_type type, + int total_size, int offset); +extern void pasemi_dma_free_chan(struct pasemi_dmachan *chan); + +extern void pasemi_dma_start_chan(const struct pasemi_dmachan *chan, + const u32 cmdsta); +extern int pasemi_dma_stop_chan(const struct pasemi_dmachan *chan); + +/* Common routines to allocate rings and buffers */ + +extern int pasemi_dma_alloc_ring(struct pasemi_dmachan *chan, int ring_size); +extern void pasemi_dma_free_ring(struct pasemi_dmachan *chan); + +extern void *pasemi_dma_alloc_buf(struct pasemi_dmachan *chan, int size, + dma_addr_t *handle); +extern void pasemi_dma_free_buf(struct pasemi_dmachan *chan, int size, + dma_addr_t *handle); + +/* Initialize the library, must be called before any other functions */ +extern int pasemi_dma_init(void); + #endif /* ASM_PASEMI_DMA_H */ -- cgit v1.2.1