diff mbox

[3/6] arm: cache-l2x0: add support for Aurora L2 cache ctrl

Message ID 1345799361-23735-4-git-send-email-gregory.clement@free-electrons.com (mailing list archive)
State New, archived
Headers show

Commit Message

Gregory CLEMENT Aug. 24, 2012, 9:09 a.m. UTC
Aurora Cache Controller was designed to be compatible with the ARM L2
Cache Controller. It comes with some difference or improvement such
as:
- no cache id part number available through hardware (need to get it
  by the DT).
- always write through mode available.
- two flavors of the controller outer cache and system cache (meaning
  maintenance operations on L1 are broadcasted to the L2 and L2
  performs the same operation).
- in outer cache mode, the cache maintenance operations are improved and
  can be done on a range inside a page and are not limited to a cache
  line.

Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Yehuda Yitschak <yehuday@marvell.com>
Cc: Barry Song <21cnbao@gmail.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Santosh Shilimkar <santosh.shilimkar@ti.com>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Olof Johansson <olof@lixom.net>
---
 arch/arm/include/asm/hardware/cache-aurora-l2.h |   51 +++++
 arch/arm/mm/cache-l2x0.c                        |  259 ++++++++++++++++++++++-
 2 files changed, 304 insertions(+), 6 deletions(-)
 create mode 100644 arch/arm/include/asm/hardware/cache-aurora-l2.h

Comments

Will Deacon Aug. 24, 2012, 10:43 a.m. UTC | #1
On Fri, Aug 24, 2012 at 10:09:18AM +0100, Gregory CLEMENT wrote:
> +static void __init aurora_broadcast_l2_commands(void)
> +{
> +       __u32 u;
> +       /* Enable Broadcasting of cache commands to L2*/
> +       __asm__ __volatile__("mrc p15, 1, %0, c15, c2, 0" : "=r"(u));
> +       u |= 0x100;             /* Set the FW bit */
> +       __asm__ __volatile__("mcr p15, 1, %0, c15, c2, 0\n" : : "r"(u));
> +}

Couple of questions about this code:

1. Is this register r/w from non-secure?
2. I'm surprised that there aren't barriers and/or maintenance operations
   needed around this operation. It might be worth checking in the
   documentation that you have (you probably need at least an isb()
   following the mcr).

Will
Sebastian Hesselbarth Aug. 24, 2012, 12:18 p.m. UTC | #2
On 8/24/12, Gregory CLEMENT <gregory.clement@free-electrons.com> wrote:
> +++ b/arch/arm/mm/cache-l2x0.c
> ...
> @@ -597,6 +838,12 @@ int __init l2x0_of_init(u32 aux_val, u32 aux_mask)

Hi all,

IMHO l2x0_of_init shouldn't rely on anything else but the compatible device node
found. Is there any other way to set aux_val and aux_mask from DT or match data?

Sebastian
Gregory CLEMENT Aug. 24, 2012, 12:45 p.m. UTC | #3
On 08/24/2012 12:43 PM, Will Deacon wrote:> On Fri, Aug 24, 2012 at 10:09:18AM +0100, Gregory CLEMENT wrote:
>> +static void __init aurora_broadcast_l2_commands(void)
>> +{
>> +       __u32 u;
>> +       /* Enable Broadcasting of cache commands to L2*/
>> +       __asm__ __volatile__("mrc p15, 1, %0, c15, c2, 0" : "=r"(u));
>> +       u |= 0x100;             /* Set the FW bit */
>> +       __asm__ __volatile__("mcr p15, 1, %0, c15, c2, 0\n" : : "r"(u));
>> +}
>
> Couple of questions about this code:
>
> 1. Is this register r/w from non-secure?

This register is banked.

> 2. I'm surprised that there aren't barriers and/or maintenance operations
>    needed around this operation. It might be worth checking in the
>    documentation that you have (you probably need at least an isb()
>    following the mcr).

I didn't find any mention of barriers and/or maintenance operations
needed around this operation, but maybe I have missed something, or it
was implicit for the people who wrote the documentation. I will ask
confirmation that we don't need this.

>
> Will
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
Gregory CLEMENT Aug. 27, 2012, 5:31 p.m. UTC | #4
On 08/24/2012 02:45 PM, Gregory CLEMENT wrote:
> On 08/24/2012 12:43 PM, Will Deacon wrote:> On Fri, Aug 24, 2012 at 10:09:18AM +0100, Gregory CLEMENT wrote:
>>> +static void __init aurora_broadcast_l2_commands(void)
>>> +{
>>> +       __u32 u;
>>> +       /* Enable Broadcasting of cache commands to L2*/
>>> +       __asm__ __volatile__("mrc p15, 1, %0, c15, c2, 0" : "=r"(u));
>>> +       u |= 0x100;             /* Set the FW bit */
>>> +       __asm__ __volatile__("mcr p15, 1, %0, c15, c2, 0\n" : : "r"(u));
>>> +}
>>
>> Couple of questions about this code:
>>
>> 1. Is this register r/w from non-secure?
> 
> This register is banked.
> 
>> 2. I'm surprised that there aren't barriers and/or maintenance operations
>>    needed around this operation. It might be worth checking in the
>>    documentation that you have (you probably need at least an isb()
>>    following the mcr).
> 
> I didn't find any mention of barriers and/or maintenance operations
> needed around this operation, but maybe I have missed something, or it
> was implicit for the people who wrote the documentation. I will ask
> confirmation that we don't need this.

I've just received confirmation that this register is  r/w from non-secure.
And that it would be good practice to have an ISB after this MCR, so I
will add this for the next version coming soon.

> 
>>
>> Will
>>
>> _______________________________________________
>> linux-arm-kernel mailing list
>> linux-arm-kernel@lists.infradead.org
>> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
Will Deacon Aug. 27, 2012, 11:49 p.m. UTC | #5
On Mon, Aug 27, 2012 at 06:31:19PM +0100, Gregory CLEMENT wrote:
> On 08/24/2012 02:45 PM, Gregory CLEMENT wrote:
> > On 08/24/2012 12:43 PM, Will Deacon wrote:> On Fri, Aug 24, 2012 at 10:09:18AM +0100, Gregory CLEMENT wrote:
> >> 2. I'm surprised that there aren't barriers and/or maintenance operations
> >>    needed around this operation. It might be worth checking in the
> >>    documentation that you have (you probably need at least an isb()
> >>    following the mcr).
> > 
> > I didn't find any mention of barriers and/or maintenance operations
> > needed around this operation, but maybe I have missed something, or it
> > was implicit for the people who wrote the documentation. I will ask
> > confirmation that we don't need this.
> 
> I've just received confirmation that this register is  r/w from non-secure.
> And that it would be good practice to have an ISB after this MCR, so I
> will add this for the next version coming soon.

That sounds about right, thanks for checking. Can you also confirm that
we don't need an explicit L2 invalidation, like we have for the
memory-mapped interface?

Cheers,

Will
diff mbox

Patch

diff --git a/arch/arm/include/asm/hardware/cache-aurora-l2.h b/arch/arm/include/asm/hardware/cache-aurora-l2.h
new file mode 100644
index 0000000..65dad20
--- /dev/null
+++ b/arch/arm/include/asm/hardware/cache-aurora-l2.h
@@ -0,0 +1,51 @@ 
+/*
+ * AURORA shared L2 cache controller support
+ *
+ * Copyright (C) 2012 Marvell
+ *
+ * Yehuda Yitschak <yehuday@marvell.com>
+ * Gregory CLEMENT <gregory.clement@free-electrons.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2.  This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#ifndef __ASM_ARM_HARDWARE_AURORA_L2_H
+#define __ASM_ARM_HARDWARE_AURORA_L2_H
+
+#define AURORA_SYNC_REG		    0x700
+#define AURORA_RANGE_BASE_ADDR_REG  0x720
+#define AURORA_FLUSH_PHY_ADDR_REG   0x7f0
+#define AURORA_INVAL_RANGE_REG	    0x774
+#define AURORA_CLEAN_RANGE_REG	    0x7b4
+#define AURORA_FLUSH_RANGE_REG	    0x7f4
+
+#define AURORA_ACR_REPLACEMENT_OFFSET	    27
+#define AURORA_ACR_REPLACEMENT_MASK	     \
+	(0x3 << AURORA_ACR_REPLACEMENT_OFFSET)
+#define AURORA_ACR_REPLACEMENT_TYPE_WAYRR    \
+	(0 << AURORA_ACR_REPLACEMENT_OFFSET)
+#define AURORA_ACR_REPLACEMENT_TYPE_LFSR     \
+	(1 << AURORA_ACR_REPLACEMENT_OFFSET)
+#define AURORA_ACR_REPLACEMENT_TYPE_SEMIPLRU \
+	(3 << AURORA_ACR_REPLACEMENT_OFFSET)
+
+#define AURORA_ACR_FORCE_WRITE_POLICY_OFFSET	0
+#define AURORA_ACR_FORCE_WRITE_POLICY_MASK	\
+	(0x3 << AURORA_ACR_FORCE_WRITE_POLICY_OFFSET)
+#define AURORA_ACR_FORCE_WRITE_POLICY_DIS	\
+	(0 << AURORA_ACR_FORCE_WRITE_POLICY_OFFSET)
+#define AURORA_ACR_FORCE_WRITE_BACK_POLICY	\
+	(1 << AURORA_ACR_FORCE_WRITE_POLICY_OFFSET)
+#define AURORA_ACR_FORCE_WRITE_THRO_POLICY	\
+	(2 << AURORA_ACR_FORCE_WRITE_POLICY_OFFSET)
+
+#define MAX_RANGE_SIZE		1024
+
+/* chose a number outside L2X0_CACHE_ID_PART_MASK to be sure to make
+ * the distinction between a number coming from hardware and a number
+ * coming from the device tree */
+#define AURORA_CACHE_ID	       0x100
+
+#endif /* __ASM_ARM_HARDWARE_AURORA_L2_H */
diff --git a/arch/arm/mm/cache-l2x0.c b/arch/arm/mm/cache-l2x0.c
index 3591940..94d96c2 100644
--- a/arch/arm/mm/cache-l2x0.c
+++ b/arch/arm/mm/cache-l2x0.c
@@ -25,6 +25,7 @@ 
 
 #include <asm/cacheflush.h>
 #include <asm/hardware/cache-l2x0.h>
+#include <asm/hardware/cache-aurora-l2.h>
 
 #define CACHE_LINE_SIZE		32
 
@@ -33,6 +34,11 @@  static DEFINE_RAW_SPINLOCK(l2x0_lock);
 static u32 l2x0_way_mask;	/* Bitmask of active ways */
 static u32 l2x0_size;
 static unsigned long sync_reg_offset = L2X0_CACHE_SYNC;
+static int l2_wt_override;
+
+/* Aurora don't have the cache ID register available, so we have to
+ * pass it though the device tree */
+static u32  cache_id_part_number_from_dt;
 
 struct l2x0_regs l2x0_saved_regs;
 
@@ -275,6 +281,130 @@  static void l2x0_flush_range(unsigned long start, unsigned long end)
 	cache_sync();
 	raw_spin_unlock_irqrestore(&l2x0_lock, flags);
 }
+/*
+ * Note that the end addresses passed to Linux primitives are
+ * noninclusive, while the hardware cache range operations use
+ * inclusive start and end addresses.
+ */
+static unsigned long calc_range_end(unsigned long start, unsigned long end)
+{
+	unsigned long range_end;
+
+	BUG_ON(start & (CACHE_LINE_SIZE - 1));
+	BUG_ON(end & (CACHE_LINE_SIZE - 1));
+
+	/*
+	 * Try to process all cache lines between 'start' and 'end'.
+	 */
+	range_end = end;
+
+	/*
+	 * Limit the number of cache lines processed at once,
+	 * since cache range operations stall the CPU pipeline
+	 * until completion.
+	 */
+	if (range_end > start + MAX_RANGE_SIZE)
+		range_end = start + MAX_RANGE_SIZE;
+
+	/*
+	 * Cache range operations can't straddle a page boundary.
+	 */
+	if (range_end > (start | (PAGE_SIZE - 1)) + 1)
+		range_end = (start | (PAGE_SIZE - 1)) + 1;
+
+	return range_end;
+}
+
+static void aurora_pa_range(unsigned long start, unsigned long end,
+			unsigned long offset)
+{
+	unsigned long flags;
+
+	/*
+	 * Make sure 'start' and 'end' reference the same page, as
+	 * L2 is PIPT and range operations only do a TLB lookup on
+	 * the start address.
+	 */
+	BUG_ON((start ^ end) & ~(PAGE_SIZE - 1));
+	raw_spin_lock_irqsave(&l2x0_lock, flags);
+	writel(start, l2x0_base + AURORA_RANGE_BASE_ADDR_REG);
+	writel(end, l2x0_base + offset);
+	raw_spin_unlock_irqrestore(&l2x0_lock, flags);
+
+	cache_sync();
+}
+
+static void aurora_inv_range(unsigned long start, unsigned long end)
+{
+	/*
+	 * Clean and invalidate partial first cache line.
+	 */
+	if (start & (CACHE_LINE_SIZE - 1)) {
+		writel((start & ~(CACHE_LINE_SIZE - 1)) & ~0x1f,
+			l2x0_base + AURORA_FLUSH_PHY_ADDR_REG);
+		cache_sync();
+		start = (start | (CACHE_LINE_SIZE - 1)) + 1;
+	}
+
+	/*
+	 * Clean and invalidate partial last cache line.
+	 */
+	if (start < end && end & (CACHE_LINE_SIZE - 1)) {
+		writel((end & ~(CACHE_LINE_SIZE - 1)) & ~0x1f,
+			l2x0_base + AURORA_FLUSH_PHY_ADDR_REG);
+		cache_sync();
+		end &= ~(CACHE_LINE_SIZE - 1);
+	}
+
+	/*
+	 * Invalidate all full cache lines between 'start' and 'end'.
+	 */
+	while (start < end) {
+		unsigned long range_end = calc_range_end(start, end);
+		aurora_pa_range(start, range_end - CACHE_LINE_SIZE,
+				AURORA_INVAL_RANGE_REG);
+		start = range_end;
+	}
+
+	dsb();
+}
+
+static void aurora_clean_range(unsigned long start, unsigned long end)
+{
+	/*
+	 * If L2 is forced to WT, the L2 will always be clean and we
+	 * don't need to do anything here.
+	 */
+	if (!l2_wt_override) {
+		start &= ~(CACHE_LINE_SIZE - 1);
+		end = (end + CACHE_LINE_SIZE - 1) & ~(CACHE_LINE_SIZE - 1);
+		while (start != end) {
+			unsigned long range_end = calc_range_end(start, end);
+			aurora_pa_range(start, range_end - CACHE_LINE_SIZE,
+					AURORA_CLEAN_RANGE_REG);
+			start = range_end;
+		}
+	}
+
+	dsb();
+}
+
+static void aurora_flush_range(unsigned long start, unsigned long end)
+{
+	if (!l2_wt_override) {
+		start &= ~(CACHE_LINE_SIZE - 1);
+		end = (end + CACHE_LINE_SIZE - 1) & ~(CACHE_LINE_SIZE - 1);
+		while (start != end) {
+			unsigned long range_end = calc_range_end(start, end);
+			aurora_pa_range(start, range_end - CACHE_LINE_SIZE,
+					AURORA_FLUSH_RANGE_REG);
+			start = range_end;
+		}
+	}
+	dsb();
+}
+
+
 
 static void l2x0_disable(void)
 {
@@ -292,11 +422,18 @@  static void l2x0_unlock(u32 cache_id)
 	int lockregs;
 	int i;
 
-	if (cache_id == L2X0_CACHE_ID_PART_L310)
+	switch (cache_id) {
+	case L2X0_CACHE_ID_PART_L310:
 		lockregs = 8;
-	else
+		break;
+	case AURORA_CACHE_ID:
+		lockregs = 4;
+		break;
+	default:
 		/* L210 and unknown types */
 		lockregs = 1;
+		break;
+	}
 
 	for (i = 0; i < lockregs; i++) {
 		writel_relaxed(0x0, l2x0_base + L2X0_LOCKDOWN_WAY_D_BASE +
@@ -312,18 +449,22 @@  void __init l2x0_init(void __iomem *base, u32 aux_val, u32 aux_mask)
 	u32 cache_id;
 	u32 way_size = 0;
 	int ways;
+	int way_size_shift = 3;
 	const char *type;
 
 	l2x0_base = base;
-
-	cache_id = readl_relaxed(l2x0_base + L2X0_CACHE_ID);
+	if (cache_id_part_number_from_dt)
+		cache_id = cache_id_part_number_from_dt;
+	else
+		cache_id = readl_relaxed(l2x0_base + L2X0_CACHE_ID)
+			& L2X0_CACHE_ID_PART_MASK;
 	aux = readl_relaxed(l2x0_base + L2X0_AUX_CTRL);
 
 	aux &= aux_mask;
 	aux |= aux_val;
 
 	/* Determine the number of ways */
-	switch (cache_id & L2X0_CACHE_ID_PART_MASK) {
+	switch (cache_id) {
 	case L2X0_CACHE_ID_PART_L310:
 		if (aux & (1 << 16))
 			ways = 16;
@@ -340,6 +481,30 @@  void __init l2x0_init(void __iomem *base, u32 aux_val, u32 aux_mask)
 		ways = (aux >> 13) & 0xf;
 		type = "L210";
 		break;
+
+	case AURORA_CACHE_ID:
+		sync_reg_offset = AURORA_SYNC_REG;
+
+		switch ((aux >> 13) & 0xf) {
+		case 3:
+			ways = 4;
+			break;
+		case 7:
+			ways = 8;
+			break;
+		case 11:
+			ways = 16;
+			break;
+		case 15:
+			ways = 32;
+			break;
+		default:
+			ways = 8;
+			break;
+		}
+		way_size_shift = 2;
+		type = "Aurora";
+		break;
 	default:
 		/* Assume unknown chips have 8 ways */
 		ways = 8;
@@ -353,7 +518,8 @@  void __init l2x0_init(void __iomem *base, u32 aux_val, u32 aux_mask)
 	 * L2 cache Size =  Way size * Number of ways
 	 */
 	way_size = (aux & L2X0_AUX_CTRL_WAY_SIZE_MASK) >> 17;
-	way_size = 1 << (way_size + 3);
+	way_size = 1 << (way_size + way_size_shift);
+
 	l2x0_size = ways * way_size * SZ_1K;
 
 	/*
@@ -489,6 +655,12 @@  static void __init pl310_save(void)
 	}
 }
 
+static void aurora_save(void)
+{
+	l2x0_saved_regs.ctrl = readl_relaxed(l2x0_base + L2X0_CTRL);
+	l2x0_saved_regs.aux_ctrl = readl_relaxed(l2x0_base + L2X0_AUX_CTRL);
+}
+
 static void l2x0_resume(void)
 {
 	if (!(readl_relaxed(l2x0_base + L2X0_CTRL) & 1)) {
@@ -534,6 +706,48 @@  static void pl310_resume(void)
 	l2x0_resume();
 }
 
+static void aurora_resume(void)
+{
+	u32 u;
+
+	u = readl(l2x0_base + L2X0_CTRL);
+	if (!(u & 1)) {
+		writel(l2x0_saved_regs.aux_ctrl, l2x0_base + L2X0_AUX_CTRL);
+		writel(l2x0_saved_regs.ctrl, l2x0_base + L2X0_CTRL);
+	}
+}
+
+static void __init aurora_broadcast_l2_commands(void)
+{
+	__u32 u;
+	/* Enable Broadcasting of cache commands to L2*/
+	__asm__ __volatile__("mrc p15, 1, %0, c15, c2, 0" : "=r"(u));
+	u |= 0x100;		/* Set the FW bit */
+	__asm__ __volatile__("mcr p15, 1, %0, c15, c2, 0\n" : : "r"(u));
+}
+
+static void __init aurora_of_setup(const struct device_node *np,
+				u32 *aux_val, u32 *aux_mask)
+{
+	u32 val = AURORA_ACR_REPLACEMENT_TYPE_SEMIPLRU;
+	u32 mask =  AURORA_ACR_REPLACEMENT_MASK;
+
+	of_property_read_u32(np, "cache-id-part",
+			&cache_id_part_number_from_dt);
+
+	/* Determine and save the write policy */
+	l2_wt_override = of_property_read_bool(np, "wt-override");
+
+	if (l2_wt_override) {
+		val |= AURORA_ACR_FORCE_WRITE_THRO_POLICY;
+		mask |= AURORA_ACR_FORCE_WRITE_POLICY_MASK;
+	}
+
+	*aux_val &= ~mask;
+	*aux_val |= val;
+	*aux_mask &= ~mask;
+}
+
 static const struct l2x0_of_data pl310_data = {
 	.setup = pl310_of_setup,
 	.save  = pl310_save,
@@ -565,10 +779,37 @@  static const struct l2x0_of_data l2x0_data = {
 	},
 };
 
+static const struct l2x0_of_data aurora_with_outer_data = {
+	.setup = aurora_of_setup,
+	.save  = aurora_save,
+	.outer_cache = {
+		.resume      = aurora_resume,
+		.inv_range   = aurora_inv_range,
+		.clean_range = aurora_clean_range,
+		.flush_range = aurora_flush_range,
+		.sync        = l2x0_cache_sync,
+		.flush_all   = l2x0_flush_all,
+		.inv_all     = l2x0_inv_all,
+		.disable     = l2x0_disable,
+	},
+};
+
+static const struct l2x0_of_data aurora_no_outer_data = {
+	.setup = aurora_of_setup,
+	.save  = aurora_save,
+	.outer_cache = {
+		.resume      = aurora_resume,
+	},
+};
+
 static const struct of_device_id l2x0_ids[] __initconst = {
 	{ .compatible = "arm,pl310-cache", .data = (void *)&pl310_data },
 	{ .compatible = "arm,l220-cache", .data = (void *)&l2x0_data },
 	{ .compatible = "arm,l210-cache", .data = (void *)&l2x0_data },
+	{ .compatible = "marvell,aurora-cache-no-outer",
+	  .data = (void *)&aurora_no_outer_data},
+	{ .compatible = "marvell,aurora-cache-with-outer",
+	  .data = (void *)&aurora_with_outer_data},
 	{}
 };
 
@@ -597,6 +838,12 @@  int __init l2x0_of_init(u32 aux_val, u32 aux_mask)
 	if (!(readl_relaxed(l2x0_base + L2X0_CTRL) & 1)) {
 		if (data->setup)
 			data->setup(np, &aux_val, &aux_mask);
+
+
+		/* For aurora cache in no outer mode select the
+		 * correct mode using the coprocessor*/
+		if (data == &aurora_no_outer_data)
+			aurora_broadcast_l2_commands();
 	}
 
 	if (data->save)