* [PATCH v8 08/12] iommu/exynos: remove prefetch buffer setting when enabling System MMU
@ 2013-07-26 11:28 Cho KyongHo
2013-07-26 17:35 ` Grant Grundler
0 siblings, 1 reply; 3+ messages in thread
From: Cho KyongHo @ 2013-07-26 11:28 UTC (permalink / raw)
To: 'Linux ARM Kernel', 'Linux IOMMU',
'Linux Kernel', 'Linux Samsung SOC'
Cc: 'Hyunwoong Kim', 'Joerg Roedel',
'Kukjin Kim', 'Prathyush', 'Rahul Sharma',
'Subash Patel', 'Keyyoung Park',
'Grant Grundler', 'Antonios Motakis', kvmarm,
'Sachin Kamat'
Prefetch buffer must be handled accurately, exact range of a buffer,
frame by frame manually. Otherwise, it may causes page fault or
deadlock in System MMU.
Thus this patch removes prefetch buffer setting when System MMU is
initialized(enabled).
Signed-off-by: Cho KyongHo <pullip.cho@samsung.com>
---
drivers/iommu/exynos-iommu.c | 32 +++++++++++++++++++++++++++-----
1 files changed, 27 insertions(+), 5 deletions(-)
diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
index cfc02ed..87f6bb7 100644
--- a/drivers/iommu/exynos-iommu.c
+++ b/drivers/iommu/exynos-iommu.c
@@ -80,6 +80,8 @@
#define CTRL_BLOCK 0x7
#define CTRL_DISABLE 0x0
+#define CFG_FLPDCACHE (1 << 20) /* System MMU 3.2+ only */
+
#define REG_MMU_CTRL 0x000
#define REG_MMU_CFG 0x004
#define REG_MMU_STATUS 0x008
@@ -96,6 +98,9 @@
#define REG_MMU_VERSION 0x034
+#define MMU_MAJ_VER(reg) (reg >> 28)
+#define MMU_MIN_VER(reg) ((reg >> 21) & 0x7F)
+
#define REG_PB0_SADDR 0x04C
#define REG_PB0_EADDR 0x050
#define REG_PB1_SADDR 0x054
@@ -200,6 +205,22 @@ static bool is_sysmmu_active(struct sysmmu_drvdata *data)
return data->activations > 0;
}
+static unsigned int __sysmmu_version(struct sysmmu_drvdata *data,
+ int idx, unsigned int *minor)
+{
+ unsigned long major;
+
+ major = readl(data->sfrbases[idx] + REG_MMU_VERSION);
+
+ if (minor)
+ *minor = MMU_MIN_VER(major);
+
+ if (MMU_MAJ_VER(major) > 3)
+ return 1;
+
+ return MMU_MAJ_VER(major);
+}
+
static void sysmmu_unblock(void __iomem *sfrbase)
{
__raw_writel(CTRL_ENABLE, sfrbase + REG_MMU_CTRL);
@@ -460,14 +481,15 @@ static int __exynos_sysmmu_enable(struct sysmmu_drvdata *data,
data->pgtable = pgtable;
for (i = 0; i < data->nsfrs; i++) {
+ unsigned int min;
+
__sysmmu_set_ptbase(data->sfrbases[i], pgtable);
- if ((readl(data->sfrbases[i] + REG_MMU_VERSION) >> 28) == 3) {
- /* System MMU version is 3.x */
- __raw_writel((1 << 12) | (2 << 28),
+ if ((__sysmmu_version(data, i, &min) == 3) && (min > 1)) {
+ unsigned long cfg;
+ cfg = __raw_readl(data->sfrbases[i] + REG_MMU_CFG);
+ __raw_writel(cfg | CFG_FLPDCACHE,
data->sfrbases[i] + REG_MMU_CFG);
- __sysmmu_set_prefbuf(data->sfrbases[i], 0, -1, 0);
- __sysmmu_set_prefbuf(data->sfrbases[i], 0, -1, 1);
}
__raw_writel(CTRL_ENABLE, data->sfrbases[i] + REG_MMU_CTRL);
--
1.7.2.5
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH v8 08/12] iommu/exynos: remove prefetch buffer setting when enabling System MMU
2013-07-26 11:28 [PATCH v8 08/12] iommu/exynos: remove prefetch buffer setting when enabling System MMU Cho KyongHo
@ 2013-07-26 17:35 ` Grant Grundler
2013-07-29 7:32 ` Cho KyongHo
0 siblings, 1 reply; 3+ messages in thread
From: Grant Grundler @ 2013-07-26 17:35 UTC (permalink / raw)
To: Cho KyongHo
Cc: Linux ARM Kernel, Linux IOMMU, Linux Kernel, Linux Samsung SOC,
Hyunwoong Kim, Joerg Roedel, Kukjin Kim, Prathyush, Rahul Sharma,
Subash Patel, Keyyoung Park, Grant Grundler, Antonios Motakis,
kvmarm, Sachin Kamat
On Fri, Jul 26, 2013 at 4:28 AM, Cho KyongHo <pullip.cho@samsung.com> wrote:
> Prefetch buffer must be handled accurately, exact range of a buffer,
> frame by frame manually. Otherwise, it may causes page fault or
> deadlock in System MMU.
> Thus this patch removes prefetch buffer setting when System MMU is
> initialized(enabled).
>
> Signed-off-by: Cho KyongHo <pullip.cho@samsung.com>
Reviewed-by: Grant Grundler <grundler@chromium.org>
BTW, cscope doesn't find any callers of exynos_sysmmu_enable().
Want to submit another patch to remove it?
(Note I'm talking about exynos_sysmmu_enable() without "__" prefix).
cheers,
grant
> ---
> drivers/iommu/exynos-iommu.c | 32 +++++++++++++++++++++++++++-----
> 1 files changed, 27 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
> index cfc02ed..87f6bb7 100644
> --- a/drivers/iommu/exynos-iommu.c
> +++ b/drivers/iommu/exynos-iommu.c
> @@ -80,6 +80,8 @@
> #define CTRL_BLOCK 0x7
> #define CTRL_DISABLE 0x0
>
> +#define CFG_FLPDCACHE (1 << 20) /* System MMU 3.2+ only */
> +
> #define REG_MMU_CTRL 0x000
> #define REG_MMU_CFG 0x004
> #define REG_MMU_STATUS 0x008
> @@ -96,6 +98,9 @@
>
> #define REG_MMU_VERSION 0x034
>
> +#define MMU_MAJ_VER(reg) (reg >> 28)
> +#define MMU_MIN_VER(reg) ((reg >> 21) & 0x7F)
> +
> #define REG_PB0_SADDR 0x04C
> #define REG_PB0_EADDR 0x050
> #define REG_PB1_SADDR 0x054
> @@ -200,6 +205,22 @@ static bool is_sysmmu_active(struct sysmmu_drvdata *data)
> return data->activations > 0;
> }
>
> +static unsigned int __sysmmu_version(struct sysmmu_drvdata *data,
> + int idx, unsigned int *minor)
> +{
> + unsigned long major;
> +
> + major = readl(data->sfrbases[idx] + REG_MMU_VERSION);
> +
> + if (minor)
> + *minor = MMU_MIN_VER(major);
> +
> + if (MMU_MAJ_VER(major) > 3)
> + return 1;
> +
> + return MMU_MAJ_VER(major);
> +}
> +
> static void sysmmu_unblock(void __iomem *sfrbase)
> {
> __raw_writel(CTRL_ENABLE, sfrbase + REG_MMU_CTRL);
> @@ -460,14 +481,15 @@ static int __exynos_sysmmu_enable(struct sysmmu_drvdata *data,
> data->pgtable = pgtable;
>
> for (i = 0; i < data->nsfrs; i++) {
> + unsigned int min;
> +
> __sysmmu_set_ptbase(data->sfrbases[i], pgtable);
>
> - if ((readl(data->sfrbases[i] + REG_MMU_VERSION) >> 28) == 3) {
> - /* System MMU version is 3.x */
> - __raw_writel((1 << 12) | (2 << 28),
> + if ((__sysmmu_version(data, i, &min) == 3) && (min > 1)) {
> + unsigned long cfg;
> + cfg = __raw_readl(data->sfrbases[i] + REG_MMU_CFG);
> + __raw_writel(cfg | CFG_FLPDCACHE,
> data->sfrbases[i] + REG_MMU_CFG);
> - __sysmmu_set_prefbuf(data->sfrbases[i], 0, -1, 0);
> - __sysmmu_set_prefbuf(data->sfrbases[i], 0, -1, 1);
> }
>
> __raw_writel(CTRL_ENABLE, data->sfrbases[i] + REG_MMU_CTRL);
> --
> 1.7.2.5
>
>
^ permalink raw reply [flat|nested] 3+ messages in thread
* RE: [PATCH v8 08/12] iommu/exynos: remove prefetch buffer setting when enabling System MMU
2013-07-26 17:35 ` Grant Grundler
@ 2013-07-29 7:32 ` Cho KyongHo
0 siblings, 0 replies; 3+ messages in thread
From: Cho KyongHo @ 2013-07-29 7:32 UTC (permalink / raw)
To: 'Grant Grundler'
Cc: 'Linux ARM Kernel', 'Linux IOMMU',
'Linux Kernel', 'Linux Samsung SOC',
'Hyunwoong Kim', 'Joerg Roedel',
'Kukjin Kim', 'Prathyush', 'Rahul Sharma',
'Subash Patel', 'Keyyoung Park',
'Antonios Motakis', kvmarm, 'Sachin Kamat'
> -----Original Message-----
> From: grundler@google.com [mailto:grundler@google.com] On Behalf Of Grant Grundler
> Sent: Saturday, July 27, 2013 2:36 AM
>
> On Fri, Jul 26, 2013 at 4:28 AM, Cho KyongHo <pullip.cho@samsung.com> wrote:
> > Prefetch buffer must be handled accurately, exact range of a buffer,
> > frame by frame manually. Otherwise, it may causes page fault or
> > deadlock in System MMU.
> > Thus this patch removes prefetch buffer setting when System MMU is
> > initialized(enabled).
> >
> > Signed-off-by: Cho KyongHo <pullip.cho@samsung.com>
>
> Reviewed-by: Grant Grundler <grundler@chromium.org>
>
> BTW, cscope doesn't find any callers of exynos_sysmmu_enable().
> Want to submit another patch to remove it?
>
> (Note I'm talking about exynos_sysmmu_enable() without "__" prefix).
Oh, I missed removing that function.
Thank you.
>
> cheers,
> grant
>
> > ---
> > drivers/iommu/exynos-iommu.c | 32 +++++++++++++++++++++++++++-----
> > 1 files changed, 27 insertions(+), 5 deletions(-)
> >
> > diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
> > index cfc02ed..87f6bb7 100644
> > --- a/drivers/iommu/exynos-iommu.c
> > +++ b/drivers/iommu/exynos-iommu.c
> > @@ -80,6 +80,8 @@
> > #define CTRL_BLOCK 0x7
> > #define CTRL_DISABLE 0x0
> >
> > +#define CFG_FLPDCACHE (1 << 20) /* System MMU 3.2+ only */
> > +
> > #define REG_MMU_CTRL 0x000
> > #define REG_MMU_CFG 0x004
> > #define REG_MMU_STATUS 0x008
> > @@ -96,6 +98,9 @@
> >
> > #define REG_MMU_VERSION 0x034
> >
> > +#define MMU_MAJ_VER(reg) (reg >> 28)
> > +#define MMU_MIN_VER(reg) ((reg >> 21) & 0x7F)
> > +
> > #define REG_PB0_SADDR 0x04C
> > #define REG_PB0_EADDR 0x050
> > #define REG_PB1_SADDR 0x054
> > @@ -200,6 +205,22 @@ static bool is_sysmmu_active(struct sysmmu_drvdata *data)
> > return data->activations > 0;
> > }
> >
> > +static unsigned int __sysmmu_version(struct sysmmu_drvdata *data,
> > + int idx, unsigned int *minor)
> > +{
> > + unsigned long major;
> > +
> > + major = readl(data->sfrbases[idx] + REG_MMU_VERSION);
> > +
> > + if (minor)
> > + *minor = MMU_MIN_VER(major);
> > +
> > + if (MMU_MAJ_VER(major) > 3)
> > + return 1;
> > +
> > + return MMU_MAJ_VER(major);
> > +}
> > +
> > static void sysmmu_unblock(void __iomem *sfrbase)
> > {
> > __raw_writel(CTRL_ENABLE, sfrbase + REG_MMU_CTRL);
> > @@ -460,14 +481,15 @@ static int __exynos_sysmmu_enable(struct sysmmu_drvdata *data,
> > data->pgtable = pgtable;
> >
> > for (i = 0; i < data->nsfrs; i++) {
> > + unsigned int min;
> > +
> > __sysmmu_set_ptbase(data->sfrbases[i], pgtable);
> >
> > - if ((readl(data->sfrbases[i] + REG_MMU_VERSION) >> 28) == 3) {
> > - /* System MMU version is 3.x */
> > - __raw_writel((1 << 12) | (2 << 28),
> > + if ((__sysmmu_version(data, i, &min) == 3) && (min > 1)) {
> > + unsigned long cfg;
> > + cfg = __raw_readl(data->sfrbases[i] + REG_MMU_CFG);
> > + __raw_writel(cfg | CFG_FLPDCACHE,
> > data->sfrbases[i] + REG_MMU_CFG);
> > - __sysmmu_set_prefbuf(data->sfrbases[i], 0, -1, 0);
> > - __sysmmu_set_prefbuf(data->sfrbases[i], 0, -1, 1);
> > }
> >
> > __raw_writel(CTRL_ENABLE, data->sfrbases[i] + REG_MMU_CTRL);
> > --
> > 1.7.2.5
> >
> >
^ permalink raw reply [flat|nested] 3+ messages in thread
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2013-07-26 11:28 [PATCH v8 08/12] iommu/exynos: remove prefetch buffer setting when enabling System MMU Cho KyongHo
2013-07-26 17:35 ` Grant Grundler
2013-07-29 7:32 ` Cho KyongHo
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