Re: [PATCH linux-2.6.13-rc3] SATA: rewritten sil24 driver
From: Tejun Heo
Date: Sat Jul 30 2005 - 03:19:42 EST
Hello, Jeff.
I'll answer to your comments in this mail (and several questions,
too) and will soon post patches fixing things in separate mails.
On Thu, Jul 28, 2005 at 04:27:37PM -0400, Jeff Garzik wrote:
> Tejun Heo wrote:
> > Hello, Jeff.
> >
> > This is rewritten sil24 driver against v2.6.13-rc3. It seems to work
> >and am currently running stress test on it (random raw read of
> >concurrency 4, repeatitive mount/copy/checksup/unmount). I'll keep
> >running stress test for at least 12 hours and let you know if
> >something goes wrong. I've also tested basic error handling and it
> >seems to work.
>
> I've merged this into the 'sil24' branch of libata-dev.git, and moved
> the original driver from Silicon Image into the 'sil24-original' branch.
>
> So, please submit an incremental patch for any future changes to this
> driver.
>
> Comments below, need a few fixups before pushing upstream, most likely.
>
> Also, a question: do you have hardware docs?
>
Unfortunately, no. I've written this driver soley based on the SII's
preview driver. It would be great if I can obtain the hardware docs,
so that I can do things more properly and try NCQ and ATAPI.
>
> >diff --git a/drivers/scsi/Kconfig b/drivers/scsi/Kconfig
> >--- a/drivers/scsi/Kconfig
> >+++ b/drivers/scsi/Kconfig
> >@@ -499,6 +499,14 @@ config SCSI_SATA_SIL
> >
> > If unsure, say N.
> >
> >+config SCSI_SATA_SIL24
> >+ tristate "Silicon Image 3124/3132 SATA support"
> >+ depends on SCSI_SATA && PCI && EXPERIMENTAL
> >+ help
> >+ This option enables support for Silicon Image 3124/3132 Serial ATA.
> >+
> >+ If unsure, say N.
> >+
> > config SCSI_SATA_SIS
> > tristate "SiS 964/180 SATA support"
> > depends on SCSI_SATA && PCI && EXPERIMENTAL
> >diff --git a/drivers/scsi/Makefile b/drivers/scsi/Makefile
> >--- a/drivers/scsi/Makefile
> >+++ b/drivers/scsi/Makefile
> >@@ -126,6 +126,7 @@ obj-$(CONFIG_SCSI_ATA_PIIX) += libata.o
> > obj-$(CONFIG_SCSI_SATA_PROMISE) += libata.o sata_promise.o
> > obj-$(CONFIG_SCSI_SATA_QSTOR) += libata.o sata_qstor.o
> > obj-$(CONFIG_SCSI_SATA_SIL) += libata.o sata_sil.o
> >+obj-$(CONFIG_SCSI_SATA_SIL24) += libata.o sata_sil24.o
> > obj-$(CONFIG_SCSI_SATA_VIA) += libata.o sata_via.o
> > obj-$(CONFIG_SCSI_SATA_VITESSE) += libata.o sata_vsc.o
> > obj-$(CONFIG_SCSI_SATA_SIS) += libata.o sata_sis.o
> >diff --git a/drivers/scsi/sata_sil24.c b/drivers/scsi/sata_sil24.c
> >new file mode 100644
> >--- /dev/null
> >+++ b/drivers/scsi/sata_sil24.c
> >@@ -0,0 +1,786 @@
> >+/*
> >+ * sata_sil24.c - Driver for Silicon Image 3124/3132 SATA-2 controllers
> >+ *
> >+ * Copyright 2005 Tejun Heo
> >+ *
> >+ * Based on preview driver from Silicon Image.
> >+ *
> >+ * NOTE: No NCQ/ATAPI support yet. The preview driver didn't support
> >+ * NCQ nor ATAPI, and, unfortunately, I couldn't find out how to make
> >+ * those work. Enabling those shouldn't be difficult. Basic
> >+ * structure is all there (in libata-dev tree). If you have any
> >+ * information about this hardware, please contact me or linux-ide.
> >+ * Info is needed on...
> >+ *
> >+ * - How to issue tagged commands and turn on sactive on issue
> >accordingly.
> >+ * - Where to put an ATAPI command and how to tell the device to send it.
> >+ * - How to enable/use 64bit.
> >+ *
> >+ * This program is free software; you can redistribute it and/or modify it
> >+ * under the terms of the GNU General Public License as published by the
> >+ * Free Software Foundation; either version 2, or (at your option) any
> >+ * later version.
> >+ *
> >+ * 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.
> >+ *
> >+ */
> >+
> >+#include <linux/kernel.h>
> >+#include <linux/module.h>
> >+#include <linux/pci.h>
> >+#include <linux/blkdev.h>
> >+#include <linux/delay.h>
> >+#include <linux/interrupt.h>
> >+#include <linux/dma-mapping.h>
> >+#include <scsi/scsi_host.h>
> >+#include "scsi.h"
> >+#include <linux/libata.h>
> >+#include <asm/io.h>
> >+
> >+#define DRV_NAME "sata_sil24"
> >+#define DRV_VERSION "0.20" /* Silicon Image's preview driver was 0.10 */
> >+
> >+#define NR_PORTS 4
> >+
> >+/*
> >+ * Port request block (PRB) 32 bytes
> >+ */
> >+struct sil24_prb {
> >+ u16 ctrl;
> >+ u16 prot;
> >+ u32 rx_cnt;
> >+ u8 fis[6 * 4];
> >+};
> >+
> >+/*
> >+ * Scatter gather entry (SGE) 16 bytes
> >+ */
> >+struct sil24_sge {
> >+ u64 addr;
> >+ u32 cnt;
> >+ u32 flags;
> >+};
> >+
> >+/*
> >+ * Port multiplier
> >+ */
> >+struct sil24_port_multiplier {
> >+ u32 diag;
> >+ u32 sactive;
> >+};
>
> I know this is unlikely, but just asking... you didn't test this with a
> port multiplier, did you?
>
No, the structure is there just for completness (the preview driver
had it). If I can get the docs and access to a port multiplier, I'm
willing to implement PM support though. Is any multiplier on sale? I
cannot find any on online shops over here.
>
> >+enum {
> >+ /*
> >+ * Global controller registers (128 bytes @ BAR0)
> >+ */
> >+ /* 32 bit regs */
> >+ HOST_SLOT_STAT = 0x00, /* 32 bit slot stat * 4 */
> >+ HOST_CTRL = 0x40,
> >+ HOST_IRQ_STAT = 0x44,
> >+ HOST_PHY_CFG = 0x48,
> >+ HOST_BIST_CTRL = 0x50,
> >+ HOST_BIST_PTRN = 0x54,
> >+ HOST_BIST_STAT = 0x58,
> >+ HOST_MEM_BIST_STAT = 0x5c,
> >+ HOST_FLASH_CMD = 0x70,
> >+ /* 8 bit regs */
> >+ HOST_FLASH_DATA = 0x74,
> >+ HOST_TRANSITION_DETECT = 0x75,
> >+ HOST_GPIO_CTRL = 0x76,
> >+ HOST_I2C_ADDR = 0x78, /* 32 bit */
> >+ HOST_I2C_DATA = 0x7c,
> >+ HOST_I2C_XFER_CNT = 0x7e,
> >+ HOST_I2C_CTRL = 0x7f,
> >+
> >+ /* HOST_SLOT_STAT bits */
> >+ HOST_SSTAT_ATTN = (1 << 31),
> >+
> >+ /*
> >+ * Port registers
> >+ * (8192 bytes @ +0x0000, +0x2000, +0x4000 and +0x6000 @ BAR2)
> >+ */
> >+ PORT_REGS_SIZE = 0x2000,
> >+ PORT_PRB = 0x0000, /* (32 bytes PRB + 16 bytes SGEs *
> >6) * 31 (3968 bytes) */
> >+ /* TF is overlayed w/ PRB regs in the preview driver,
> >+ * but it doesn't seem to work. */
> >+ PORT_TF = 0x0000,
> >+
> >+ PORT_PM = 0x0f80, /* 8 bytes PM * 16 (128 bytes) */
> >+ /* 32 bit regs */
> >+ PORT_CTRL_STAT = 0x1000, /* write:ctrl, read:stat */
> >+ PORT_CTRL_CLR = 0x1004,
> >+ PORT_IRQ_STAT = 0x1008,
> >+ PORT_IRQ_ENABLE_SET = 0x1010,
> >+ PORT_IRQ_ENABLE_CLR = 0x1014,
> >+ PORT_ACTIVATE_UPPER_ADDR= 0x101c,
> >+ PORT_EXEC_FIFO = 0x1020,
> >+ PORT_CMD_ERR = 0x1024,
> >+ PORT_FIS_CFG = 0x1028,
> >+ PORT_FIFO_THRES = 0x102c,
> >+ /* 16 bit regs */
> >+ PORT_DECODE_ERR_CNT = 0x1040,
> >+ PORT_DECODE_ERR_THRESH = 0x1042,
> >+ PORT_CRC_ERR_CNT = 0x1044,
> >+ PORT_CRC_ERR_THRESH = 0x1046,
> >+ PORT_HSHK_ERR_CNT = 0x1048,
> >+ PORT_HSHK_ERR_THRESH = 0x104a,
> >+ /* 32 bit regs */
> >+ PORT_PHY_CFG = 0x1050,
> >+ PORT_SLOT_STAT = 0x1800,
> >+ PORT_CMD_ACTIVATE = 0x1c00, /* 64 bit cmd activate * 31 (248
> >bytes) */
> >+ PORT_EXEC_DIAG = 0x1e00, /* 32bit exec diag * 16 (64 bytes,
> >0-10 used on 3124) */
> >+ PORT_PSD_DIAG = 0x1e40, /* 32bit psd diag * 16 (64 bytes,
> >0-8 used on 3124) */
> >+ PORT_SCONTROL = 0x1f00,
> >+ PORT_SSTATUS = 0x1f04,
> >+ PORT_SERROR = 0x1f08,
> >+ PORT_SACTIVE = 0x1f0c,
> >+
> >+ /* PORT_CTRL_STAT bits */
> >+ PORT_CS_PORT_RST = (1 << 0), /* port reset */
> >+ PORT_CS_DEV_RST = (1 << 1), /* device reset */
> >+ PORT_CS_INIT = (1 << 2), /* port initialize */
> >+ PORT_CS_IRQ_WOC = (1 << 3), /* interrupt write one to clear
> >*/
> >+ PORT_CS_RESUME = (1 << 4), /* port resume */
> >+ PORT_CS_32BIT_ACTV = (1 << 5), /* 32-bit activation */
> >+ PORT_CS_PM_EN = (1 << 6), /* port multiplier enable */
> >+ PORT_CS_RDY = (1 << 7), /* port ready to accept commands
> >*/
> >+
> >+ /* PORT_IRQ_STAT/ENABLE_SET/CLR */
> >+ /* bits[11:0] are masked */
> >+ PORT_IRQ_COMPLETE = (1 << 0), /* command(s) completed */
> >+ PORT_IRQ_ERROR = (1 << 1), /* command execution error */
> >+ PORT_IRQ_PORTRDY_CHG = (1 << 2), /* port ready change */
> >+ PORT_IRQ_PWR_CHG = (1 << 3), /* power management change */
> >+ PORT_IRQ_PHYRDY_CHG = (1 << 4), /* PHY ready change */
> >+ PORT_IRQ_COMWAKE = (1 << 5), /* COMWAKE received */
> >+ PORT_IRQ_UNK_FIS = (1 << 6), /* Unknown FIS received */
> >+ PORT_IRQ_SDB_FIS = (1 << 11), /* SDB FIS received */
> >+
> >+ /* bits[27:16] are unmasked (raw) */
> >+ PORT_IRQ_RAW_SHIFT = 16,
> >+ PORT_IRQ_MASKED_MASK = 0x7ff,
> >+ PORT_IRQ_RAW_MASK = (0x7ff << PORT_IRQ_RAW_SHIFT),
> >+
> >+ /* ENABLE_SET/CLR specific, intr steering - 2 bit field */
> >+ PORT_IRQ_STEER_SHIFT = 30,
> >+ PORT_IRQ_STEER_MASK = (3 << PORT_IRQ_STEER_SHIFT),
> >+
> >+ /* PORT_CMD_ERR constants */
> >+ PORT_CERR_DEV = 1, /* Error bit in D2H Register FIS */
> >+ PORT_CERR_SDB = 2, /* Error bit in SDB FIS */
> >+ PORT_CERR_DATA = 3, /* Error in data FIS not detected by
> >dev */
> >+ PORT_CERR_SEND = 4, /* Initial cmd FIS transmission failure
> >*/
> >+ PORT_CERR_INCONSISTENT = 5, /* Protocol mismatch */
> >+ PORT_CERR_DIRECTION = 6, /* Data direction mismatch */
> >+ PORT_CERR_UNDERRUN = 7, /* Ran out of SGEs while writing */
> >+ PORT_CERR_OVERRUN = 8, /* Ran out of SGEs while reading */
> >+ PORT_CERR_PKT_PROT = 11, /* DIR invalid in 1st PIO setup of
> >ATAPI */
> >+ PORT_CERR_SGT_BOUNDARY = 16, /* PLD ecode 00 - SGT not on qword
> >boundary */
> >+ PORT_CERR_SGT_TGTABRT = 17, /* PLD ecode 01 - target abort */
> >+ PORT_CERR_SGT_MSTABRT = 18, /* PLD ecode 10 - master abort */
> >+ PORT_CERR_SGT_PCIPERR = 19, /* PLD ecode 11 - PCI parity err while
> >fetching SGT */
> >+ PORT_CERR_CMD_BOUNDARY = 24, /* ctrl[15:13] 001 - PRB not on qword
> >boundary */
> >+ PORT_CERR_CMD_TGTABRT = 25, /* ctrl[15:13] 010 - target abort */
> >+ PORT_CERR_CMD_MSTABRT = 26, /* ctrl[15:13] 100 - master abort */
> >+ PORT_CERR_CMD_PCIPERR = 27, /* ctrl[15:13] 110 - PCI parity err
> >while fetching PRB */
> >+ PORT_CERR_XFR_UNDEF = 32, /* PSD ecode 00 - undefined */
> >+ PORT_CERR_XFR_TGTABRT = 33, /* PSD ecode 01 - target abort */
> >+ PORT_CERR_XFR_MSGABRT = 34, /* PSD ecode 10 - master abort */
> >+ PORT_CERR_XFR_PCIPERR = 35, /* PSD ecode 11 - PCI prity err during
> >transfer */
> >+ PORT_CERR_SENDSERVICE = 36, /* FIS received whiel sending service
> >*/
> >+
> >+ /*
> >+ * Other constants
> >+ */
> >+ SGE_TRM = (1 << 31), /* Last SGE in chain */
> >+ PRB_SOFT_RST = (1 << 7), /* Soft reset request (ign
> >BSY?) */
> >+
> >+ /* board id */
> >+ BID_SIL3124 = 0,
> >+ BID_SIL3132 = 1,
> >+
> >+ IRQ_STAT_4PORTS = 0xf,
> >+};
> >+
> >+struct sil24_cmd_block {
> >+ struct sil24_prb prb;
> >+ struct sil24_sge sge[LIBATA_MAX_PRD];
> >+};
> >+
> >+/*
> >+ * ap->private_data
> >+ *
> >+ * The preview driver always returned 0 for status. We emulate it
> >+ * here from the previous interrupt.
> >+ */
> >+struct sil24_port_priv {
> >+ void *port;
> >+ struct sil24_cmd_block *cmd_block; /* 32 cmd blocks */
> >+ dma_addr_t cmd_block_dma; /* DMA base addr for them */
> >+};
> >+
> >+/* ap->host_set->private_data */
> >+struct sil24_host_priv {
> >+ void *host_base; /* global controller control (128 bytes
> >@BAR0) */
> >+ void *port_base; /* port registers (4 * 8192 bytes @BAR2) */
> >+};
> >+
> >+static u8 sil24_check_status(struct ata_port *ap);
> >+static u8 sil24_check_err(struct ata_port *ap);
> >+static u32 sil24_scr_read(struct ata_port *ap, unsigned sc_reg);
> >+static void sil24_scr_write(struct ata_port *ap, unsigned sc_reg, u32
> >val);
> >+static void sil24_phy_reset(struct ata_port *ap);
> >+static void sil24_qc_prep(struct ata_queued_cmd *qc);
> >+static int sil24_qc_issue(struct ata_queued_cmd *qc);
> >+static void sil24_irq_clear(struct ata_port *ap);
> >+static void sil24_eng_timeout(struct ata_port *ap);
> >+static irqreturn_t sil24_interrupt(int irq, void *dev_instance, struct
> >pt_regs *regs);
> >+static int sil24_port_start(struct ata_port *ap);
> >+static void sil24_port_stop(struct ata_port *ap);
> >+static void sil24_host_stop(struct ata_host_set *host_set);
> >+static int sil24_init_one(struct pci_dev *pdev, const struct
> >pci_device_id *ent);
> >+
> >+static struct pci_device_id sil24_pci_tbl[] = {
> >+ { 0x1095, 0x3124, PCI_ANY_ID, PCI_ANY_ID, 0, 0, BID_SIL3124 },
> >+ { 0x1095, 0x3132, PCI_ANY_ID, PCI_ANY_ID, 0, 0, BID_SIL3132 },
> >+};
> >+
> >+static struct pci_driver sil24_pci_driver = {
> >+ .name = DRV_NAME,
> >+ .id_table = sil24_pci_tbl,
> >+ .probe = sil24_init_one,
> >+ .remove = ata_pci_remove_one, /* safe? */
> >+};
> >+
> >+static Scsi_Host_Template sil24_sht = {
> >+ .module = THIS_MODULE,
> >+ .name = DRV_NAME,
> >+ .ioctl = ata_scsi_ioctl,
> >+ .queuecommand = ata_scsi_queuecmd,
> >+ .eh_strategy_handler = ata_scsi_error,
> >+ .can_queue = ATA_DEF_QUEUE,
> >+ .this_id = ATA_SHT_THIS_ID,
> >+ .sg_tablesize = LIBATA_MAX_PRD,
> >+ .max_sectors = ATA_MAX_SECTORS,
> >+ .cmd_per_lun = ATA_SHT_CMD_PER_LUN,
> >+ .emulated = ATA_SHT_EMULATED,
> >+ .use_clustering = ATA_SHT_USE_CLUSTERING,
> >+ .proc_name = DRV_NAME,
> >+ .dma_boundary = ATA_DMA_BOUNDARY,
> >+ .slave_configure = ata_scsi_slave_config,
> >+ .bios_param = ata_std_bios_param,
> >+ .ordered_flush = 1, /* NCQ not supported yet */
> >+};
> >+
> >+static struct ata_port_operations sil24_ops = {
> >+ .port_disable = ata_port_disable,
> >+
> >+ .check_status = sil24_check_status,
> >+ .check_altstatus = sil24_check_status,
> >+ .check_err = sil24_check_err,
> >+ .dev_select = ata_noop_dev_select,
> >+
> >+ .phy_reset = sil24_phy_reset,
> >+
> >+ .qc_prep = sil24_qc_prep,
> >+ .qc_issue = sil24_qc_issue,
> >+
> >+ .eng_timeout = sil24_eng_timeout,
> >+
> >+ .irq_handler = sil24_interrupt,
> >+ .irq_clear = sil24_irq_clear,
> >+
> >+ .scr_read = sil24_scr_read,
> >+ .scr_write = sil24_scr_write,
> >+
> >+ .port_start = sil24_port_start,
> >+ .port_stop = sil24_port_stop,
> >+ .host_stop = sil24_host_stop,
> >+};
> >+
> >+static struct ata_port_info sil24_port_info[] = {
> >+ /* sil_3124 */
> >+ {
> >+ .sht = &sil24_sht,
> >+ .host_flags = ATA_FLAG_SATA | ATA_FLAG_NO_LEGACY |
> >+ ATA_FLAG_SATA_RESET | ATA_FLAG_MMIO |
> >+ ATA_FLAG_PIO_DMA,
> >+ .pio_mask = 0x1f, /* pio0-4 */
> >+ .mwdma_mask = 0x07, /* mwdma0-2 */
> >+ .udma_mask = 0x3f, /* udma0-5 */
> >+ .port_ops = &sil24_ops,
> >+ },
> >+ /* sil_3132 */
> >+ {
> >+ .sht = &sil24_sht,
> >+ .host_flags = ATA_FLAG_SATA | ATA_FLAG_NO_LEGACY |
> >+ ATA_FLAG_SATA_RESET | ATA_FLAG_MMIO |
> >+ ATA_FLAG_PIO_DMA,
> >+ .pio_mask = 0x1f, /* pio0-4 */
> >+ .mwdma_mask = 0x07, /* mwdma0-2 */
> >+ .udma_mask = 0x3f, /* udma0-5 */
> >+ .port_ops = &sil24_ops,
> >+ },
> >+};
> >+
> >+static u8 sil24_check_status(struct ata_port *ap)
> >+{
> >+ return ATA_DRDY;
> >+}
> >+
> >+static u8 sil24_check_err(struct ata_port *ap)
> >+{
> >+ return 0;
> >+}
>
> For these two functions, we need to grab the values for these registers
> from the D2H Register FIS. These should not be constant values, they
> are used in probing.
>
Sadly I don't know where the values are. The original driver seems
to assume that taskfile registers are overlayed with PORT_PRB, but
they are not. Values are bogus there. Again, in need of hardware
docs here.
The original rewritten sil24 driver against NCQ helpers had simple
status register emulation using normal/error completion interrupt. I
don't know why I stripped that while converting the driver over
vanilla libata (sorry). I'll restore it. It's not good, but it
correctly indicates error on error.
>
> >+static int sil24_scr_map[] = {
> >+ [SCR_CONTROL] = 0,
> >+ [SCR_STATUS] = 1,
> >+ [SCR_ERROR] = 2,
> >+ [SCR_ACTIVE] = 3,
> >+};
> >+
> >+static u32 sil24_scr_read(struct ata_port *ap, unsigned sc_reg)
> >+{
> >+ void *scr_addr = (void *)ap->ioaddr.scr_addr;
> >+ if (sc_reg < ARRAY_SIZE(sil24_scr_map)) {
> >+ void *addr;
> >+ addr = scr_addr + sil24_scr_map[sc_reg] * 4;
> >+ return readl(scr_addr + sil24_scr_map[sc_reg] * 4);
> >+ }
> >+ return 0xffffffffU;
> >+}
> >+
> >+static void sil24_scr_write(struct ata_port *ap, unsigned sc_reg, u32 val)
> >+{
> >+ void *scr_addr = (void *)ap->ioaddr.scr_addr;
> >+ if (sc_reg < ARRAY_SIZE(sil24_scr_map)) {
> >+ void *addr;
> >+ addr = scr_addr + sil24_scr_map[sc_reg] * 4;
> >+ writel(val, scr_addr + sil24_scr_map[sc_reg] * 4);
> >+ }
> >+}
> >+
> >+static void sil24_phy_reset(struct ata_port *ap)
> >+{
> >+ __sata_phy_reset(ap);
> >+ /*
> >+ * No ATAPI yet. Just unconditionally indicate ATA device.
> >+ * If ATAPI device is attached, it will fail ATA_CMD_ID_ATA
> >+ * and libata core will ignore the device.
> >+ */
> >+ if (!(ap->flags & ATA_FLAG_PORT_DISABLED))
> >+ ap->device[0].class = ATA_DEV_ATA;
> >+}
>
> We need to use the standard probing code to figure this out.
> ata_dev_classify(), etc.
>
Again, the problem here is that I don't know how to access the
signature values after reset. The preview driver didn't do that and
maybe that's why they duplicated the whole reset-probe procedure. The
above code always forces ATA_DEV_ATA signature after reset which makes
ata_dev_identify() always use ATA_CMD_ID_ATA which will be failed by
the drive (with soon-to-be-posted status fix... :-). So, it's a bit
hacky but achieves ATA-only support with very few lines.
Maybe the proper thing here would be...
* get information on how to access signature information and set class
to ATA_DEV_NONE if ATAPI. (Or, even better, add proper ATAPI support)
* if signature info is inaccessible, we can implement ATA_FLAG_NOSIG
flag and let libata layer figure out what's attached using both
ATA_CMD_ID_ATA and ATA_CMD_ID_ATAPI.
>
> >+static inline void sil24_fill_sg(struct ata_queued_cmd *qc,
> >+ struct sil24_cmd_block *cb)
> >+{
> >+ struct scatterlist *sg = qc->sg;
> >+ struct sil24_sge *sge = cb->sge;
> >+ unsigned i;
> >+
> >+ for (i = 0; i < qc->n_elem; i++, sg++, sge++) {
> >+ sge->addr = cpu_to_le64(sg_dma_address(sg));
> >+ sge->cnt = cpu_to_le32(sg_dma_len(sg));
> >+ sge->flags = 0;
> >+ sge->flags = i < qc->n_elem - 1 ? 0 : cpu_to_le32(SGE_TRM);
> >+ }
> >+}
> >+
> >+static void sil24_qc_prep(struct ata_queued_cmd *qc)
> >+{
> >+ struct ata_port *ap = qc->ap;
> >+ struct sil24_port_priv *pp = ap->private_data;
> >+ struct sil24_cmd_block *cb = pp->cmd_block + qc->tag;
> >+ struct sil24_prb *prb = &cb->prb;
> >+
> >+ switch (qc->tf.protocol) {
> >+ case ATA_PROT_PIO:
> >+ case ATA_PROT_DMA:
> >+ case ATA_PROT_NODATA:
> >+ break;
> >+ default:
> >+ /* ATAPI isn't supported yet */
> >+ BUG();
> >+ }
> >+
> >+ ata_tf_to_fis(&qc->tf, prb->fis, 0);
> >+
> >+ if (qc->flags & ATA_QCFLAG_DMAMAP)
> >+ sil24_fill_sg(qc, cb);
> >+}
> >+
> >+static int sil24_qc_issue(struct ata_queued_cmd *qc)
> >+{
> >+ struct ata_port *ap = qc->ap;
> >+ struct sil24_port_priv *pp = ap->private_data;
> >+ dma_addr_t paddr = pp->cmd_block_dma + qc->tag *
> >sizeof(*pp->cmd_block);
> >+
> >+ writel((u32)paddr, pp->port + PORT_CMD_ACTIVATE);
> >+ return 0;
> >+}
> >+
> >+static void sil24_irq_clear(struct ata_port *ap)
> >+{
> >+ /* unused */
> >+}
>
> we need to fill this in.
>
AFAIK, this function will be called only from ata_device_add(). As
we call that function after resetting all status (including
interrupts), this callback isn't really useful in this case, I think.
>
> >+static void sil24_reset_controller(struct ata_port *ap)
> >+{
> >+ struct sil24_port_priv *pp = ap->private_data;
> >+ void *port = pp->port;
> >+ int cnt;
> >+ u32 tmp;
> >+
> >+ printk(KERN_NOTICE DRV_NAME
> >+ " ata%u: resetting controller...\n", ap->id);
> >+
> >+ /* Reset controller state. Is this correct? */
> >+ writel(PORT_CS_DEV_RST, port + PORT_CTRL_STAT);
> >+ readl(port + PORT_CTRL_STAT); /* sync */
> >+
> >+ /* Max ~100ms */
> >+ for (cnt = 0; cnt < 1000; cnt++) {
> >+ udelay(100);
> >+ tmp = readl(port + PORT_CTRL_STAT);
> >+ if (!(tmp & PORT_CS_DEV_RST))
> >+ break;
> >+ }
>
> Use mdelay. We should be able to sleep here?
>
> Either way, we want to avoid long delays like this.
>
With NCQ-helpers changes, all errors are handled in EH thread (NCQ
device or not), so original rewritten driver uses msleep, but here we
cannot as sil24_host_intr calls this function on error (I know it's
bad... but AHCI does the same way currently). And the reset procedure
is what I've found by trial & error, so I don't know what the upper
time limit is. I can change it to cnt < 100, msleep(1) or whatever
else, as it's an arbitrary value anyway. Again, more information
needed.
>
> >+ if (tmp & PORT_CS_DEV_RST)
> >+ printk(KERN_ERR DRV_NAME
> >+ " ata%u: failed to reset controller\n", ap->id);
> >+}
> >+
> >+static void sil24_eng_timeout(struct ata_port *ap)
> >+{
> >+ struct ata_queued_cmd *qc;
> >+
> >+ qc = ata_qc_from_tag(ap, ap->active_tag);
> >+ if (!qc) {
> >+ printk(KERN_ERR "ata%u: BUG: tiemout without command\n",
> >+ ap->id);
> >+ return;
> >+ }
> >+
> >+ /*
> >+ * hack alert! We cannot use the supplied completion
> >+ * function from inside the ->eh_strategy_handler() thread.
> >+ * libata is the only user of ->eh_strategy_handler() in
> >+ * any kernel, so the default scsi_done() assumes it is
> >+ * not being called from the SCSI EH.
> >+ */
> >+ printk(KERN_ERR "ata%u: command timeout\n", ap->id);
> >+ qc->scsidone = scsi_finish_command;
> >+ ata_qc_complete(qc, ATA_ERR);
> >+
> >+ sil24_reset_controller(ap);
> >+}
> >+
> >+static inline void sil24_host_intr(struct ata_port *ap)
> >+{
> >+ struct ata_queued_cmd *qc = ata_qc_from_tag(ap, ap->active_tag);
> >+ struct sil24_port_priv *pp = ap->private_data;
> >+ void *port = pp->port;
> >+ u32 slot_stat;
> >+
> >+ slot_stat = readl(port + PORT_SLOT_STAT);
> >+ if (!(slot_stat & HOST_SSTAT_ATTN)) {
> >+ if (qc)
> >+ ata_qc_complete(qc, 0);
> >+ } else {
> >+ u32 irq_stat, cmd_err, sstatus, serror;
> >+
> >+ irq_stat = readl(port + PORT_IRQ_STAT);
> >+ cmd_err = readl(port + PORT_CMD_ERR);
> >+ sstatus = readl(port + PORT_SSTATUS);
> >+ serror = readl(port + PORT_SERROR);
> >+
> >+ /* Clear IRQ/errors */
> >+ writel(irq_stat, port + PORT_IRQ_STAT);
> >+ if (cmd_err)
> >+ writel(cmd_err, port + PORT_CMD_ERR);
> >+ if (serror)
> >+ writel(serror, port + PORT_SERROR);
> >+
> >+ printk(KERN_ERR DRV_NAME " ata%u: error interrupt on
> >port%d\n"
> >+ " stat=0x%x irq=0x%x cmd_err=%d sstatus=0x%x
> >serror=0x%x\n",
> >+ ap->id, ap->port_no, slot_stat, irq_stat, cmd_err,
> >sstatus, serror);
> >+
> >+ if (qc)
> >+ ata_qc_complete(qc, ATA_ERR);
> >+
> >+ sil24_reset_controller(ap);
> >+ }
> >+}
>
> Two comments:
> 1) The "OK" test for command completion seems quite fragile. I think
> the code may be -assuming- a command is completed. I'll have to check
> the docs to see if HOST_IRQ_STAT + no-other-events truly guarantees an
> indication of command completion.
>
It's from the preview driver. DOCS, PLEASE. :-)
> 2) Error handling should be moved out-of-line, in a separate function.
Sure.
>
> >+static irqreturn_t sil24_interrupt(int irq, void *dev_instance, struct
> >pt_regs *regs)
> >+{
> >+ struct ata_host_set *host_set = dev_instance;
> >+ struct sil24_host_priv *hpriv = host_set->private_data;
> >+ unsigned handled = 0;
> >+ u32 status;
> >+ int i;
> >+
> >+ status = readl(hpriv->host_base + HOST_IRQ_STAT);
> >+
> >+ if (!(status & IRQ_STAT_4PORTS))
> >+ goto out;
>
> also check for status==0xffffffff to indicate PCI bus fault, or hardware
> unplug.
>
Okay. Hmmm... Out of curiosity, are we supposed to do this kind of
test in all drivers? Can you please point me to information regarding
this?
>
> >+ spin_lock(&host_set->lock);
> >+
> >+ for (i = 0; i < host_set->n_ports; i++)
> >+ if (status & (1 << i)) {
> >+ struct ata_port *ap = host_set->ports[i];
> >+ if (ap && !(ap->flags & ATA_FLAG_PORT_DISABLED))
> >+ sil24_host_intr(host_set->ports[i]);
> >+ else {
> >+ u32 tmp;
> >+ printk(KERN_WARNING DRV_NAME
> >+ ": spurious interrupt from port
> >%d\n", i);
> >+ tmp = readl(hpriv->host_base + HOST_CTRL);
> >+ tmp &= ~(1 << i);
> >+ writel(tmp, hpriv->host_base + HOST_CTRL);
>
> add a comment describing what these three lines of code do
>
The code disables interrupt for the port which has generated spurious
interrupt. The original code just printed a message and told IRQ
subsystem that it isn't ours, possibly causing "nobody cared" error.
So, this piece of code is what I've added. I think I'll enable IRQs
just for enabled ports and remove the disabling code here.
>
> >+ }
> >+ handled++;
> >+ }
> >+
> >+ spin_unlock(&host_set->lock);
> >+ out:
> >+ return IRQ_RETVAL(handled);
> >+}
> >+
> >+static int sil24_port_start(struct ata_port *ap)
> >+{
> >+ struct device *dev = ap->host_set->dev;
> >+ struct sil24_host_priv *hpriv = ap->host_set->private_data;
> >+ struct sil24_port_priv *pp;
> >+ struct sil24_cmd_block *cb;
> >+ size_t cb_size = sizeof(*cb);
> >+ dma_addr_t cb_dma;
> >+
> >+ pp = kmalloc(sizeof(*pp), GFP_KERNEL);
> >+ if (!pp)
> >+ return -ENOMEM;
> >+ memset(pp, 0, sizeof(*pp));
> >+
> >+ cb = dma_alloc_coherent(dev, cb_size, &cb_dma, GFP_KERNEL);
> >+ if (!cb) {
> >+ kfree(pp);
> >+ return -ENOMEM;
> >+ }
> >+ memset(cb, 0, cb_size);
> >+
> >+ pp->port = hpriv->port_base + ap->port_no * PORT_REGS_SIZE;
> >+ pp->cmd_block = cb;
> >+ pp->cmd_block_dma = cb_dma;
> >+
> >+ ap->private_data = pp;
> >+
> >+ return 0;
> >+}
> >+
> >+static void sil24_port_stop(struct ata_port *ap)
> >+{
> >+ struct device *dev = ap->host_set->dev;
> >+ struct sil24_port_priv *pp = ap->private_data;
> >+ size_t cb_size = sizeof(*pp->cmd_block);
> >+
> >+ dma_free_coherent(dev, cb_size, pp->cmd_block, pp->cmd_block_dma);
> >+ kfree(pp);
> >+}
> >+
> >+static void sil24_host_stop(struct ata_host_set *host_set)
> >+{
> >+ struct sil24_host_priv *hpriv = host_set->private_data;
> >+
> >+ iounmap(hpriv->host_base);
> >+ iounmap(hpriv->port_base);
> >+ kfree(hpriv);
> >+}
> >+
> >+static int sil24_init_one(struct pci_dev *pdev, const struct
> >pci_device_id *ent)
> >+{
> >+ static int printed_version = 0;
> >+ unsigned int board_id = (unsigned int)ent->driver_data;
> >+ struct ata_probe_ent *probe_ent = NULL;
> >+ struct sil24_host_priv *hpriv = NULL;
> >+ void *host_base = NULL, *port_base = NULL;
> >+ int i, rc;
> >+
> >+ if (!printed_version++)
> >+ printk(KERN_DEBUG DRV_NAME " version " DRV_VERSION "\n");
> >+
> >+ rc = pci_enable_device(pdev);
> >+ if (rc)
> >+ return rc;
> >+
> >+ rc = pci_request_regions(pdev, DRV_NAME);
> >+ if (rc)
> >+ goto out_disable;
> >+
> >+ rc = -ENOMEM;
> >+ /* ioremap mmio registers */
> >+ host_base = ioremap(pci_resource_start(pdev, 0),
> >+ pci_resource_len(pdev, 0));
> >+ if (!host_base)
> >+ goto out_free;
> >+ port_base = ioremap(pci_resource_start(pdev, 2),
> >+ pci_resource_len(pdev, 2));
> >+ if (!port_base)
> >+ goto out_free;
> >+ /* allocate & init probe_ent and hpriv */
> >+ probe_ent = kmalloc(sizeof(*probe_ent), GFP_KERNEL);
> >+ if (!probe_ent)
> >+ goto out_free;
> >+
> >+ hpriv = kmalloc(sizeof(*hpriv), GFP_KERNEL);
> >+ if (!hpriv)
> >+ goto out_free;
> >+
> >+ memset(probe_ent, 0, sizeof(*probe_ent));
> >+ probe_ent->dev = pci_dev_to_dev(pdev);
> >+ INIT_LIST_HEAD(&probe_ent->node);
> >+
> >+ probe_ent->sht = sil24_port_info[board_id].sht;
> >+ probe_ent->host_flags = sil24_port_info[board_id].host_flags;
> >+ probe_ent->pio_mask = sil24_port_info[board_id].pio_mask;
> >+ probe_ent->udma_mask = sil24_port_info[board_id].udma_mask;
> >+ probe_ent->port_ops = sil24_port_info[board_id].port_ops;
> >+ probe_ent->n_ports = (board_id == BID_SIL3124) ? 4 : 2;
> >+
> >+ probe_ent->irq = pdev->irq;
> >+ probe_ent->irq_flags = SA_SHIRQ;
> >+ probe_ent->mmio_base = port_base;
> >+ probe_ent->private_data = hpriv;
> >+
> >+ memset(hpriv, 0, sizeof(*hpriv));
> >+ hpriv->host_base = host_base;
> >+ hpriv->port_base = port_base;
> >+
> >+ /*
> >+ * Configure the device
> >+ */
> >+ /*
> >+ * FIXME: This device is certainly 64-bit capable. We just
> >+ * don't know how to use it. After fixing 32bit activation in
> >+ * this function, enable 64bit masks here.
> >+ */
>
> elaboration?
>
In the preview driver, while initializing port, PORT_CSR_M_32BIT_ACTV
is written to CtrlSetStatus. I don't know what it really means and
have no means of testing it as I don't have any machine with more than
4gigs of memory. So, I wasn't really sure if that 32 bit applies only
to consistent memory (maybe it's 32bit activation address?) or also to
DMA buffers. That's why I just used 32bit masks for both of them.
Again, with docs, this should be easy to fix.
>
> >+ rc = pci_set_dma_mask(pdev, DMA_32BIT_MASK);
> >+ if (rc) {
> >+ printk(KERN_ERR DRV_NAME "(%s): 32-bit DMA enable failed\n",
> >+ pci_name(pdev));
> >+ goto out_free;
> >+ }
> >+ rc = pci_set_consistent_dma_mask(pdev, DMA_32BIT_MASK);
> >+ if (rc) {
> >+ printk(KERN_ERR DRV_NAME "(%s): 32-bit consistent DMA enable
> >failed\n",
> >+ pci_name(pdev));
> >+ goto out_free;
> >+ }
> >+
> >+ /* GPIO off */
> >+ writel(0, host_base + HOST_FLASH_CMD);
> >+
> >+ /* Mask interrupts during initialization */
> >+ writel(0, host_base + HOST_CTRL);
>
> add a readl() to flush this write out to the PCI bus ("PCI posting")
>
Sure. And, out of curiosity, isn't sync unnecessary unless we're
gonna perform some kind of timed waiting following it? We don't have
any timing requirement after above interrupt masking, do we?
>
> >+ for (i = 0; i < probe_ent->n_ports; i++) {
> >+ void *port = port_base + i * PORT_REGS_SIZE;
> >+ unsigned long portu = (unsigned long)port;
> >+ u32 tmp;
> >+ int cnt;
> >+
> >+ probe_ent->port[i].cmd_addr = portu + PORT_TF;
> >+ probe_ent->port[i].ctl_addr = portu + PORT_TF + 0xa;
> >+ probe_ent->port[i].altstatus_addr = portu + PORT_TF + 0xa;
> >+ probe_ent->port[i].scr_addr = portu + PORT_SCONTROL;
> >+
> >+ ata_std_ports(&probe_ent->port[i]);
> >+
> >+ /* Initial PHY setting */
> >+ writel(0x20c, port + PORT_PHY_CFG);
> >+
> >+ /* Clear port RST */
> >+ tmp = readl(port + PORT_CTRL_STAT);
> >+ if (tmp & PORT_CS_PORT_RST) {
> >+ writel(PORT_CS_PORT_RST, port + PORT_CTRL_CLR);
> >+ readl(port + PORT_CTRL_STAT); /* sync */
> >+ for (cnt = 0; cnt < 10; cnt++) {
> >+ msleep(10);
> >+ tmp = readl(port + PORT_CTRL_STAT);
> >+ if (!(tmp & PORT_CS_PORT_RST))
> >+ break;
> >+ }
> >+ if (tmp & PORT_CS_PORT_RST)
> >+ printk(KERN_ERR DRV_NAME
> >+ "(%s): failed to clear port RST\n",
> >+ pci_name(pdev));
> >+ }
>
> this is already done in sata_phy_reset()?
>
I don't know what PORT_RST does here. This is what the preview
driver does, so... If it's the same thing as phy reset using SATA
SCR, we can remove it. Again, docs needed.
>
> >+ /* Zero error counters. */
> >+ writel(0x8000, port + PORT_DECODE_ERR_THRESH);
> >+ writel(0x8000, port + PORT_CRC_ERR_THRESH);
> >+ writel(0x8000, port + PORT_HSHK_ERR_THRESH);
> >+ writel(0x0000, port + PORT_DECODE_ERR_CNT);
> >+ writel(0x0000, port + PORT_CRC_ERR_CNT);
> >+ writel(0x0000, port + PORT_HSHK_ERR_CNT);
> >+
> >+ /* FIXME: 32bit activation? */
> >+ writel(0, port + PORT_ACTIVATE_UPPER_ADDR);
> >+ writel(PORT_CS_32BIT_ACTV, port + PORT_CTRL_STAT);
> >+
> >+ /* Configure interrupts */
> >+ writel(0xffff, port + PORT_IRQ_ENABLE_CLR);
> >+ writel(PORT_IRQ_COMPLETE | PORT_IRQ_ERROR | PORT_IRQ_SDB_FIS,
> >+ port + PORT_IRQ_ENABLE_SET);
> >+
> >+ /* Clear interrupts */
> >+ writel(0x0fff0fff, port + PORT_IRQ_STAT);
> >+ writel(PORT_CS_IRQ_WOC, port + PORT_CTRL_CLR);
> >+ }
> >+
> >+ /* Turn on interrupts */
> >+ writel(IRQ_STAT_4PORTS, host_base + HOST_CTRL);
> >+
> >+ pci_set_master(pdev);
> >+
> >+ ata_device_add(probe_ent);
>
> as with other drivers, add FIXME comment, indicating that the return
> value should be checked, and if ata_device_add() failed.
>
Sure.
>
> >+ kfree(probe_ent);
> >+ return 0;
> >+
> >+ out_free:
> >+ if (host_base)
> >+ iounmap(host_base);
> >+ if (port_base)
> >+ iounmap(port_base);
> >+ kfree(probe_ent);
> >+ kfree(hpriv);
> >+ pci_release_regions(pdev);
> >+ out_disable:
> >+ pci_disable_device(pdev);
> >+ return rc;
> >+}
> >+
> >+static int __init sil24_init(void)
> >+{
> >+ return pci_module_init(&sil24_pci_driver);
> >+}
> >+
> >+static void __exit sil24_exit(void)
> >+{
> >+ pci_unregister_driver(&sil24_pci_driver);
> >+}
> >+
> >+MODULE_AUTHOR("Tejun Heo");
> >+MODULE_DESCRIPTION("Silicon Image 3124/3132 SATA low-level driver");
> >+MODULE_LICENSE("GPL");
> >+MODULE_DEVICE_TABLE(pci, sil24_pci_tbl);
> >+
> >+module_init(sil24_init);
> >+module_exit(sil24_exit);
> >
--
tejun
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