[PATCH 4/4 v5] iommu/fsl: Freescale PAMU driver and IOMMU API implementation.
Timur Tabi
timur at freescale.com
Wed Nov 21 09:52:53 EST 2012
Varun Sethi wrote:
> diff --git a/drivers/iommu/fsl_pamu.h b/drivers/iommu/fsl_pamu.h
> new file mode 100644
> index 0000000..6d32fb5
> --- /dev/null
> +++ b/drivers/iommu/fsl_pamu.h
> @@ -0,0 +1,398 @@
> +/*
> + * 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, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
> + *
> + * Copyright (C) 2012 Freescale Semiconductor, Inc.
> + *
> + */
> +
> +#ifndef __FSL_PAMU_H
> +#define __FSL_PAMU_H
> +
> +/* Bit Field macros
> + * v = bit field variable; m = mask, m##_SHIFT = shift, x = value to load
> + */
> +#define set_bf(v, m, x) (v = ((v) & ~(m)) | (((x) << (m##_SHIFT)) & (m)))
> +#define get_bf(v, m) (((v) & (m)) >> (m##_SHIFT))
> +
> +/* PAMU CCSR space */
> +#define PAMU_PGC 0x00000000 /* Allows all peripheral accesses */
> +#define PAMU_PE 0x40000000 /* enable PAMU */
> +
> +/* PAMU_OFFSET to the next pamu space in ccsr */
> +#define PAMU_OFFSET 0x1000
> +
> +#define PAMU_MMAP_REGS_BASE 0
> +
> +struct pamu_mmap_regs {
> + u32 ppbah;
> + u32 ppbal;
> + u32 pplah;
> + u32 pplal;
> + u32 spbah;
> + u32 spbal;
> + u32 splah;
> + u32 splal;
> + u32 obah;
> + u32 obal;
> + u32 olah;
> + u32 olal;
> +};
> +
> +/* PAMU Error Registers */
> +#define PAMU_POES1 0x0040
> +#define PAMU_POES2 0x0044
> +#define PAMU_POEAH 0x0048
> +#define PAMU_POEAL 0x004C
> +#define PAMU_AVS1 0x0050
> +#define PAMU_AVS1_AV 0x1
> +#define PAMU_AVS1_OTV 0x6
> +#define PAMU_AVS1_APV 0x78
> +#define PAMU_AVS1_WAV 0x380
> +#define PAMU_AVS1_LAV 0x1c00
> +#define PAMU_AVS1_GCV 0x2000
> +#define PAMU_AVS1_PDV 0x4000
> +#define PAMU_AV_MASK (PAMU_AVS1_AV | PAMU_AVS1_OTV | PAMU_AVS1_APV | PAMU_AVS1_WAV \
> + | PAMU_AVS1_LAV | PAMU_AVS1_GCV | PAMU_AVS1_PDV)
> +#define PAMU_AVS1_LIODN_SHIFT 16
> +#define PAMU_LAV_LIODN_NOT_IN_PPAACT 0x400
I think you can move most of macros in this .h file into one of the .c files.
> diff --git a/drivers/iommu/fsl_pamu_domain.c b/drivers/iommu/fsl_pamu_domain.c
> new file mode 100644
> index 0000000..d473447
> --- /dev/null
> +++ b/drivers/iommu/fsl_pamu_domain.c
The code in this file is generally hard to read because you
1) have very few comments
2) you have a lot of expressions that span several lines, like this one:
if ((iova >= geom_attr->aperture_start &&
iova < geom_attr->aperture_end - 1 &&
size <= geom_size) &&
!align_check) {
Try adding a few more comments (e.g. each function should be commented)
and maybe try to break up a few of these lines.
> @@ -0,0 +1,978 @@
> +/*
> + * 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, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
> + *
> + * Copyright (C) 2012 Freescale Semiconductor, Inc.
> + * Author: Varun Sethi <varun.sethi at freescale.com>
> + *
> + */
> +
> +#define pr_fmt(fmt) "fsl-pamu-domain: %s: " fmt, __func__
You don't use this macro.
> +
> +#include <linux/init.h>
> +#include <linux/iommu.h>
> +#include <linux/notifier.h>
> +#include <linux/slab.h>
> +#include <linux/module.h>
> +#include <linux/types.h>
> +#include <linux/mm.h>
> +#include <linux/interrupt.h>
> +#include <linux/device.h>
> +#include <linux/of_platform.h>
> +#include <linux/bootmem.h>
> +#include <linux/err.h>
> +#include <asm/io.h>
> +#include <asm/bitops.h>
> +
> +#include "fsl_pamu_domain.h"
> +
> +/* This bitmap advertises the page sizes supported by PAMU hardware
> + * to the IOMMU API.
> + */
> +#define FSL_PAMU_PGSIZES (~0xFFFUL)
> +
> +/* global spinlock that needs to be held while
> + * configuring PAMU.
> + */
> +static DEFINE_SPINLOCK(iommu_lock);
> +
> +static struct kmem_cache *fsl_pamu_domain_cache;
> +static struct kmem_cache *iommu_devinfo_cache;
> +static DEFINE_SPINLOCK(device_domain_lock);
> +
> +int __init iommu_init_mempool(void)
> +{
> +
> + fsl_pamu_domain_cache = kmem_cache_create("fsl_pamu_domain",
> + sizeof(struct fsl_dma_domain),
> + 0,
> + SLAB_HWCACHE_ALIGN,
> +
> + NULL);
> + if (!fsl_pamu_domain_cache) {
> + pr_err("Couldn't create fsl iommu_domain cache\n");
ALL of these pr_xxx functions (in the entire file) need to have a
"fsl-pamu-domain:" prefix. Maybe that's why you created pr_fmt(), but you
forgot to use it.
The above message should look like this:
pr_err("fsl-pamu-domain: could not create iommu domain cache\n");
> + return -ENOMEM;
> + }
> +
> + iommu_devinfo_cache = kmem_cache_create("iommu_devinfo",
> + sizeof(struct device_domain_info),
> + 0,
> + SLAB_HWCACHE_ALIGN,
> + NULL);
> + if (!iommu_devinfo_cache) {
> + pr_err("Couldn't create devinfo cache\n");
> + kmem_cache_destroy(fsl_pamu_domain_cache);
> + return -ENOMEM;
> + }
> +
> + return 0;
> +}
> +
> +
> +static int reconfig_win(int liodn, struct fsl_dma_domain *domain)
> +{
> + int ret;
> +
> + spin_lock(&iommu_lock);
> + ret = pamu_config_ppaace(liodn, domain->mapped_iova,
> + domain->mapped_size,
> + ~(u32)0,
> + domain->paddr >> PAMU_PAGE_SHIFT,
> + domain->snoop_id, domain->stash_id,
> + 0, domain->prot);
> + spin_unlock(&iommu_lock);
> + if (ret) {
> + pr_err("PAMU PAACE configuration failed for liodn %d\n",
> + liodn);
> + }
> + return ret;
> +}
> +
> +static void update_domain_subwin(struct fsl_dma_domain *dma_domain,
> + unsigned long iova, size_t size,
> + phys_addr_t paddr, int prot, int status)
> +{
> + struct iommu_domain *domain = dma_domain->iommu_domain;
> + u32 subwin_cnt = dma_domain->subwin_cnt;
> + dma_addr_t geom_size = dma_domain->geom_size;
> + u32 subwin_size;
> + u32 mapped_subwin;
> + u32 mapped_subwin_cnt;
> + struct dma_subwindow *sub_win_ptr;
> + int i;
> +
> + subwin_size = geom_size >> ilog2(subwin_cnt);
> + mapped_subwin = (iova - domain->geometry.aperture_start)
> + >> ilog2(subwin_size);
> + sub_win_ptr = &dma_domain->sub_win_arr[mapped_subwin];
> + mapped_subwin_cnt = (size < subwin_size) ? 1 :
> + size >> ilog2(subwin_size);
> + for (i = 0; i < mapped_subwin_cnt; i++) {
> + if (status) {
> + sub_win_ptr[i].paddr = paddr;
> + sub_win_ptr[i].size = (size < subwin_size) ?
> + size : subwin_size;
> + paddr += subwin_size;
> + sub_win_ptr[i].iova = iova;
> + iova += subwin_size;
> + }
> + sub_win_ptr[i].valid = status;
> + sub_win_ptr[i].prot = prot;
> + }
> +
> + dma_domain->mapped_subwin = mapped_subwin;
> + dma_domain->mapped_subwin_cnt = mapped_subwin_cnt;
> +}
> +
> +static int reconfig_subwin(int liodn, struct fsl_dma_domain *dma_domain)
> +{
> + u32 subwin_cnt = dma_domain->subwin_cnt;
> + int ret = 0;
> + u32 mapped_subwin;
> + u32 mapped_subwin_cnt;
> + struct dma_subwindow *sub_win_ptr;
> + unsigned long rpn;
> + int i;
> +
> + mapped_subwin = dma_domain->mapped_subwin;
> + mapped_subwin_cnt = dma_domain->mapped_subwin_cnt;
> + sub_win_ptr = &dma_domain->sub_win_arr[mapped_subwin];
> +
> + for (i = 0; i < mapped_subwin_cnt; i++) {
> + rpn = sub_win_ptr[i].paddr >> PAMU_PAGE_SHIFT,
> +
> + spin_lock(&iommu_lock);
> + ret = pamu_config_spaace(liodn, subwin_cnt, mapped_subwin,
> + sub_win_ptr[i].size,
> + ~(u32)0,
> + rpn, dma_domain->snoop_id,
> + dma_domain->stash_id,
> + (mapped_subwin == 0 &&
> + !dma_domain->enabled) ?
> + 0 : sub_win_ptr[i].valid,
Break out this expression into another variable. This code is illegible.
int enabled = 0;
for (...
if (mapped_subwin || dma_domain->enabled)
enabled = sub_win_ptr[i].valid;
> + sub_win_ptr[i].prot);
> + spin_unlock(&iommu_lock);
> + if (ret) {
> + pr_err("PAMU SPAACE configuration failed for liodn %d\n",liodn);
> + return ret;
> + }
> + mapped_subwin++;
> + }
> +
> + return ret;
> +}
> +
> +static phys_addr_t get_phys_addr(struct fsl_dma_domain *dma_domain, unsigned long iova)
> +{
> + u32 subwin_cnt = dma_domain->subwin_cnt;
> +
> + if (subwin_cnt) {
> + int i;
> + struct dma_subwindow *sub_win_ptr =
> + &dma_domain->sub_win_arr[0];
> +
> + for (i = 0; i < subwin_cnt; i++) {
> + if (sub_win_ptr[i].valid &&
> + iova >= sub_win_ptr[i].iova &&
> + iova < (sub_win_ptr[i].iova +
> + sub_win_ptr[i].size - 1))
> + return (sub_win_ptr[i].paddr + (iova &
> + (sub_win_ptr[i].size - 1)));
> + }
> + } else {
> + return (dma_domain->paddr + (iova & (dma_domain->mapped_size - 1)));
> + }
> +
> + return 0;
> +}
> +
> +static int map_liodn_subwins(int liodn, struct fsl_dma_domain *dma_domain, u32 subwin_cnt)
> +{
> + struct dma_subwindow *sub_win_ptr =
> + &dma_domain->sub_win_arr[0];
> + int i, ret;
> + unsigned long rpn;
> +
> + for (i = 0; i < subwin_cnt; i++) {
> + if (sub_win_ptr[i].valid) {
> + rpn = sub_win_ptr[i].paddr >>
> + PAMU_PAGE_SHIFT,
> + spin_lock(&iommu_lock);
> + ret = pamu_config_spaace(liodn, subwin_cnt, i,
> + sub_win_ptr[i].size,
> + ~(u32)0,
> + rpn,
> + dma_domain->snoop_id,
> + dma_domain->stash_id,
> + (i > 0) ? 1 : 0,
> + sub_win_ptr[i].prot);
> + spin_unlock(&iommu_lock);
> + if (ret) {
> + pr_err("PAMU SPAACE configuration failed for liodn %d\n",
> + liodn);
> + return ret;
> + }
> + }
> + }
> +
> + return ret;
> +}
> +
> +static int map_liodn_win(int liodn, struct fsl_dma_domain *dma_domain)
> +{
> + unsigned long rpn;
> + int ret;
> +
> + rpn = dma_domain->paddr >> PAMU_PAGE_SHIFT;
> + spin_lock(&iommu_lock);
> + ret = pamu_config_ppaace(liodn, dma_domain->mapped_iova,
> + dma_domain->mapped_size,
> + ~(u32)0,
> + rpn,
> + dma_domain->snoop_id, dma_domain->stash_id,
> + 0, dma_domain->prot);
Indentation problem
> + spin_unlock(&iommu_lock);
> + if (ret)
> + pr_err("PAMU PAACE configuration failed for liodn %d\n",
> + liodn);
> +
> + return ret;
> +}
> +
> +static int map_liodn(int liodn, struct fsl_dma_domain *dma_domain)
> +{
> + u32 subwin_cnt = dma_domain->subwin_cnt;
> +
> + if (subwin_cnt)
> + return map_liodn_subwins(liodn, dma_domain, subwin_cnt);
> + else
> + return map_liodn_win(liodn, dma_domain);
> +
> +}
> +
> +static int update_liodn(int liodn, struct fsl_dma_domain *dma_domain)
> +{
> + int ret;
> +
> + if (dma_domain->subwin_cnt) {
> + ret = reconfig_subwin(liodn, dma_domain);
> + if (ret)
> + pr_err("Subwindow reconfiguration failed for liodn %d\n", liodn);
> + } else {
> + ret = reconfig_win(liodn, dma_domain);
> + if (ret)
> + pr_err("Window reconfiguration failed for liodn %d\n", liodn);
> + }
> +
> + return ret;
> +}
> +
> +static int update_liodn_stash(int liodn, struct fsl_dma_domain *dma_domain,
> + u32 val)
> +{
> + int ret = 0, i;
> +
> + spin_lock(&iommu_lock);
> + if (!dma_domain->subwin_cnt) {
> + ret = pamu_update_paace_stash(liodn, 0, val);
> + if (ret) {
> + pr_err("Failed to update PAACE field for liodn %d\n ", liodn);
> + spin_unlock(&iommu_lock);
> + return ret;
> + }
> + } else {
> + for (i = 0; i < dma_domain->subwin_cnt; i++) {
> + ret = pamu_update_paace_stash(liodn, i, val);
> + if (ret) {
> + pr_err("Failed to update SPAACE %d field for liodn %d\n ", i, liodn);
> + spin_unlock(&iommu_lock);
> + return ret;
> + }
> + }
> + }
> + spin_unlock(&iommu_lock);
> +
> + return ret;
> +}
> +
> +static int configure_liodn(int liodn, struct device *dev,
> + struct fsl_dma_domain *dma_domain,
> + struct iommu_domain_geometry *geom_attr,
> + u32 subwin_cnt)
> +{
> + phys_addr_t window_addr, window_size;
> + phys_addr_t subwin_size;
> + int ret = 0, i;
> + u32 omi_index = ~(u32)0;
> +
> + /* Configure the omi_index at the geometry setup time.
> + * This is a static value which depends on the type of
> + * device and would not change thereafter.
> + */
/*
* multi-line comments
* look like this
*/
--
Timur Tabi
Linux kernel developer at Freescale
More information about the Linuxppc-dev
mailing list