diff options
| author | Mark Brown <[email protected]> | 2015-10-12 18:09:27 +0100 | 
|---|---|---|
| committer | Mark Brown <[email protected]> | 2015-10-12 18:09:27 +0100 | 
| commit | 79828b4fa835f73cdaf4bffa48696abdcbea9d02 (patch) | |
| tree | 5e0fa7156acb75ba603022bc807df8f2fedb97a8 /arch/x86/platform/intel/iosf_mbi.c | |
| parent | 721b51fcf91898299d96f4b72cb9434cda29dce6 (diff) | |
| parent | 8c1a9d6323abf0fb1e5dad96cf3f1c783505ea5a (diff) | |
Merge remote-tracking branch 'asoc/fix/rt5645' into asoc-fix-rt5645
Diffstat (limited to 'arch/x86/platform/intel/iosf_mbi.c')
| -rw-r--r-- | arch/x86/platform/intel/iosf_mbi.c | 327 | 
1 files changed, 327 insertions, 0 deletions
diff --git a/arch/x86/platform/intel/iosf_mbi.c b/arch/x86/platform/intel/iosf_mbi.c new file mode 100644 index 000000000000..edf2c54bf131 --- /dev/null +++ b/arch/x86/platform/intel/iosf_mbi.c @@ -0,0 +1,327 @@ +/* + * IOSF-SB MailBox Interface Driver + * Copyright (c) 2013, Intel Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope 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. + * + * + * The IOSF-SB is a fabric bus available on Atom based SOC's that uses a + * mailbox interface (MBI) to communicate with mutiple devices. This + * driver implements access to this interface for those platforms that can + * enumerate the device using PCI. + */ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/spinlock.h> +#include <linux/pci.h> +#include <linux/debugfs.h> +#include <linux/capability.h> + +#include <asm/iosf_mbi.h> + +#define PCI_DEVICE_ID_BAYTRAIL		0x0F00 +#define PCI_DEVICE_ID_BRASWELL		0x2280 +#define PCI_DEVICE_ID_QUARK_X1000	0x0958 +#define PCI_DEVICE_ID_TANGIER		0x1170 + +static struct pci_dev *mbi_pdev; +static DEFINE_SPINLOCK(iosf_mbi_lock); + +static inline u32 iosf_mbi_form_mcr(u8 op, u8 port, u8 offset) +{ +	return (op << 24) | (port << 16) | (offset << 8) | MBI_ENABLE; +} + +static int iosf_mbi_pci_read_mdr(u32 mcrx, u32 mcr, u32 *mdr) +{ +	int result; + +	if (!mbi_pdev) +		return -ENODEV; + +	if (mcrx) { +		result = pci_write_config_dword(mbi_pdev, MBI_MCRX_OFFSET, +						mcrx); +		if (result < 0) +			goto fail_read; +	} + +	result = pci_write_config_dword(mbi_pdev, MBI_MCR_OFFSET, mcr); +	if (result < 0) +		goto fail_read; + +	result = pci_read_config_dword(mbi_pdev, MBI_MDR_OFFSET, mdr); +	if (result < 0) +		goto fail_read; + +	return 0; + +fail_read: +	dev_err(&mbi_pdev->dev, "PCI config access failed with %d\n", result); +	return result; +} + +static int iosf_mbi_pci_write_mdr(u32 mcrx, u32 mcr, u32 mdr) +{ +	int result; + +	if (!mbi_pdev) +		return -ENODEV; + +	result = pci_write_config_dword(mbi_pdev, MBI_MDR_OFFSET, mdr); +	if (result < 0) +		goto fail_write; + +	if (mcrx) { +		result = pci_write_config_dword(mbi_pdev, MBI_MCRX_OFFSET, +						mcrx); +		if (result < 0) +			goto fail_write; +	} + +	result = pci_write_config_dword(mbi_pdev, MBI_MCR_OFFSET, mcr); +	if (result < 0) +		goto fail_write; + +	return 0; + +fail_write: +	dev_err(&mbi_pdev->dev, "PCI config access failed with %d\n", result); +	return result; +} + +int iosf_mbi_read(u8 port, u8 opcode, u32 offset, u32 *mdr) +{ +	u32 mcr, mcrx; +	unsigned long flags; +	int ret; + +	/* Access to the GFX unit is handled by GPU code */ +	if (port == BT_MBI_UNIT_GFX) { +		WARN_ON(1); +		return -EPERM; +	} + +	mcr = iosf_mbi_form_mcr(opcode, port, offset & MBI_MASK_LO); +	mcrx = offset & MBI_MASK_HI; + +	spin_lock_irqsave(&iosf_mbi_lock, flags); +	ret = iosf_mbi_pci_read_mdr(mcrx, mcr, mdr); +	spin_unlock_irqrestore(&iosf_mbi_lock, flags); + +	return ret; +} +EXPORT_SYMBOL(iosf_mbi_read); + +int iosf_mbi_write(u8 port, u8 opcode, u32 offset, u32 mdr) +{ +	u32 mcr, mcrx; +	unsigned long flags; +	int ret; + +	/* Access to the GFX unit is handled by GPU code */ +	if (port == BT_MBI_UNIT_GFX) { +		WARN_ON(1); +		return -EPERM; +	} + +	mcr = iosf_mbi_form_mcr(opcode, port, offset & MBI_MASK_LO); +	mcrx = offset & MBI_MASK_HI; + +	spin_lock_irqsave(&iosf_mbi_lock, flags); +	ret = iosf_mbi_pci_write_mdr(mcrx, mcr, mdr); +	spin_unlock_irqrestore(&iosf_mbi_lock, flags); + +	return ret; +} +EXPORT_SYMBOL(iosf_mbi_write); + +int iosf_mbi_modify(u8 port, u8 opcode, u32 offset, u32 mdr, u32 mask) +{ +	u32 mcr, mcrx; +	u32 value; +	unsigned long flags; +	int ret; + +	/* Access to the GFX unit is handled by GPU code */ +	if (port == BT_MBI_UNIT_GFX) { +		WARN_ON(1); +		return -EPERM; +	} + +	mcr = iosf_mbi_form_mcr(opcode, port, offset & MBI_MASK_LO); +	mcrx = offset & MBI_MASK_HI; + +	spin_lock_irqsave(&iosf_mbi_lock, flags); + +	/* Read current mdr value */ +	ret = iosf_mbi_pci_read_mdr(mcrx, mcr & MBI_RD_MASK, &value); +	if (ret < 0) { +		spin_unlock_irqrestore(&iosf_mbi_lock, flags); +		return ret; +	} + +	/* Apply mask */ +	value &= ~mask; +	mdr &= mask; +	value |= mdr; + +	/* Write back */ +	ret = iosf_mbi_pci_write_mdr(mcrx, mcr | MBI_WR_MASK, value); + +	spin_unlock_irqrestore(&iosf_mbi_lock, flags); + +	return ret; +} +EXPORT_SYMBOL(iosf_mbi_modify); + +bool iosf_mbi_available(void) +{ +	/* Mbi isn't hot-pluggable. No remove routine is provided */ +	return mbi_pdev; +} +EXPORT_SYMBOL(iosf_mbi_available); + +#ifdef CONFIG_IOSF_MBI_DEBUG +static u32	dbg_mdr; +static u32	dbg_mcr; +static u32	dbg_mcrx; + +static int mcr_get(void *data, u64 *val) +{ +	*val = *(u32 *)data; +	return 0; +} + +static int mcr_set(void *data, u64 val) +{ +	u8 command = ((u32)val & 0xFF000000) >> 24, +	   port	   = ((u32)val & 0x00FF0000) >> 16, +	   offset  = ((u32)val & 0x0000FF00) >> 8; +	int err; + +	*(u32 *)data = val; + +	if (!capable(CAP_SYS_RAWIO)) +		return -EACCES; + +	if (command & 1u) +		err = iosf_mbi_write(port, +			       command, +			       dbg_mcrx | offset, +			       dbg_mdr); +	else +		err = iosf_mbi_read(port, +			      command, +			      dbg_mcrx | offset, +			      &dbg_mdr); + +	return err; +} +DEFINE_SIMPLE_ATTRIBUTE(iosf_mcr_fops, mcr_get, mcr_set , "%llx\n"); + +static struct dentry *iosf_dbg; + +static void iosf_sideband_debug_init(void) +{ +	struct dentry *d; + +	iosf_dbg = debugfs_create_dir("iosf_sb", NULL); +	if (IS_ERR_OR_NULL(iosf_dbg)) +		return; + +	/* mdr */ +	d = debugfs_create_x32("mdr", 0660, iosf_dbg, &dbg_mdr); +	if (!d) +		goto cleanup; + +	/* mcrx */ +	d = debugfs_create_x32("mcrx", 0660, iosf_dbg, &dbg_mcrx); +	if (!d) +		goto cleanup; + +	/* mcr - initiates mailbox tranaction */ +	d = debugfs_create_file("mcr", 0660, iosf_dbg, &dbg_mcr, &iosf_mcr_fops); +	if (!d) +		goto cleanup; + +	return; + +cleanup: +	debugfs_remove_recursive(d); +} + +static void iosf_debugfs_init(void) +{ +	iosf_sideband_debug_init(); +} + +static void iosf_debugfs_remove(void) +{ +	debugfs_remove_recursive(iosf_dbg); +} +#else +static inline void iosf_debugfs_init(void) { } +static inline void iosf_debugfs_remove(void) { } +#endif /* CONFIG_IOSF_MBI_DEBUG */ + +static int iosf_mbi_probe(struct pci_dev *pdev, +			  const struct pci_device_id *unused) +{ +	int ret; + +	ret = pci_enable_device(pdev); +	if (ret < 0) { +		dev_err(&pdev->dev, "error: could not enable device\n"); +		return ret; +	} + +	mbi_pdev = pci_dev_get(pdev); +	return 0; +} + +static const struct pci_device_id iosf_mbi_pci_ids[] = { +	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_BAYTRAIL) }, +	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_BRASWELL) }, +	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_QUARK_X1000) }, +	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_TANGIER) }, +	{ 0, }, +}; +MODULE_DEVICE_TABLE(pci, iosf_mbi_pci_ids); + +static struct pci_driver iosf_mbi_pci_driver = { +	.name		= "iosf_mbi_pci", +	.probe		= iosf_mbi_probe, +	.id_table	= iosf_mbi_pci_ids, +}; + +static int __init iosf_mbi_init(void) +{ +	iosf_debugfs_init(); + +	return pci_register_driver(&iosf_mbi_pci_driver); +} + +static void __exit iosf_mbi_exit(void) +{ +	iosf_debugfs_remove(); + +	pci_unregister_driver(&iosf_mbi_pci_driver); +	pci_dev_put(mbi_pdev); +	mbi_pdev = NULL; +} + +module_init(iosf_mbi_init); +module_exit(iosf_mbi_exit); + +MODULE_AUTHOR("David E. Box <[email protected]>"); +MODULE_DESCRIPTION("IOSF Mailbox Interface accessor"); +MODULE_LICENSE("GPL v2");  |