Re: [PATCH v1 2/2] rockchip: power-domain: support qos save and restore

From: Elaine Zhang
Date: Thu Mar 31 2016 - 22:38:47 EST



hi, Heiko

I agree with most of your modifications.
Except, the u32 *qos_save_regs below

On 04/01/2016 12:31 AM, Heiko Stuebner wrote:
Hi Elaine,

Am Freitag, 18. März 2016, 15:17:24 schrieb Elaine Zhang:
support qos save and restore when power domain on/off.

Signed-off-by: Elaine Zhang <zhangqing@xxxxxxxxxxxxxx>

overall looks nice already ... some implementation-specific comments below.

---
drivers/soc/rockchip/pm_domains.c | 87
+++++++++++++++++++++++++++++++++++++-- 1 file changed, 84 insertions(+),
3 deletions(-)

diff --git a/drivers/soc/rockchip/pm_domains.c
b/drivers/soc/rockchip/pm_domains.c index 18aee6b..c5f4be6 100644
--- a/drivers/soc/rockchip/pm_domains.c
+++ b/drivers/soc/rockchip/pm_domains.c
@@ -45,10 +45,21 @@ struct rockchip_pmu_info {
const struct rockchip_domain_info *domain_info;
};

+#define MAX_QOS_NODE_NUM 20
+#define MAX_QOS_REGS_NUM 5
+#define QOS_PRIORITY 0x08
+#define QOS_MODE 0x0c
+#define QOS_BANDWIDTH 0x10
+#define QOS_SATURATION 0x14
+#define QOS_EXTCONTROL 0x18
+
struct rockchip_pm_domain {
struct generic_pm_domain genpd;
const struct rockchip_domain_info *info;
struct rockchip_pmu *pmu;
+ int num_qos;
+ struct regmap *qos_regmap[MAX_QOS_NODE_NUM];
+ u32 qos_save_regs[MAX_QOS_NODE_NUM][MAX_QOS_REGS_NUM];

struct regmap **qos_regmap;
u32 *qos_save_regs;
when we save and restore qos registers we need save five regs for every qos.
like this :
for (i = 0; i < pd->num_qos; i++) {
regmap_read(pd->qos_regmap[i],
QOS_PRIORITY,
&pd->qos_save_regs[i][0]);
regmap_read(pd->qos_regmap[i],
QOS_MODE,
&pd->qos_save_regs[i][1]);
regmap_read(pd->qos_regmap[i],
QOS_BANDWIDTH,
&pd->qos_save_regs[i][2]);
regmap_read(pd->qos_regmap[i],
QOS_SATURATION,
&pd->qos_save_regs[i][3]);
regmap_read(pd->qos_regmap[i],
QOS_EXTCONTROL,
&pd->qos_save_regs[i][4]);
}
so we can not define qos_save_regs like u32 *qos_save_regs;,
and apply buff like
pd->qos_save_regs = kcalloc(pd->num_qos * MAX_QOS_REGS_NUM, sizeof(u32),
GFP_KERNEL);


int num_clks;
struct clk *clks[];
};
@@ -111,6 +122,55 @@ static int rockchip_pmu_set_idle_request(struct
rockchip_pm_domain *pd, return 0;
}

+static int rockchip_pmu_save_qos(struct rockchip_pm_domain *pd)
+{
+ int i;
+
+ for (i = 0; i < pd->num_qos; i++) {
+ regmap_read(pd->qos_regmap[i],
+ QOS_PRIORITY,
+ &pd->qos_save_regs[i][0]);
+ regmap_read(pd->qos_regmap[i],
+ QOS_MODE,
+ &pd->qos_save_regs[i][1]);
+ regmap_read(pd->qos_regmap[i],
+ QOS_BANDWIDTH,
+ &pd->qos_save_regs[i][2]);
+ regmap_read(pd->qos_regmap[i],
+ QOS_SATURATION,
+ &pd->qos_save_regs[i][3]);
+ regmap_read(pd->qos_regmap[i],
+ QOS_EXTCONTROL,
+ &pd->qos_save_regs[i][4]);
+ }
+ return 0;
+}
+
+static int rockchip_pmu_restore_qos(struct rockchip_pm_domain *pd)
+{
+ int i;
+
+ for (i = 0; i < pd->num_qos; i++) {
+ regmap_write(pd->qos_regmap[i],
+ QOS_PRIORITY,
+ pd->qos_save_regs[i][0]);
+ regmap_write(pd->qos_regmap[i],
+ QOS_MODE,
+ pd->qos_save_regs[i][1]);
+ regmap_write(pd->qos_regmap[i],
+ QOS_BANDWIDTH,
+ pd->qos_save_regs[i][2]);
+ regmap_write(pd->qos_regmap[i],
+ QOS_SATURATION,
+ pd->qos_save_regs[i][3]);
+ regmap_write(pd->qos_regmap[i],
+ QOS_EXTCONTROL,
+ pd->qos_save_regs[i][4]);
+ }
+
+ return 0;
+}
+
static bool rockchip_pmu_domain_is_on(struct rockchip_pm_domain *pd)
{
struct rockchip_pmu *pmu = pd->pmu;
@@ -147,7 +207,7 @@ static int rockchip_pd_power(struct rockchip_pm_domain
*pd, bool power_on) clk_enable(pd->clks[i]);

if (!power_on) {
- /* FIXME: add code to save AXI_QOS */
+ rockchip_pmu_save_qos(pd);

/* if powering down, idle request to NIU first */
rockchip_pmu_set_idle_request(pd, true);
@@ -159,7 +219,7 @@ static int rockchip_pd_power(struct rockchip_pm_domain
*pd, bool power_on) /* if powering up, leave idle mode */
rockchip_pmu_set_idle_request(pd, false);

- /* FIXME: add code to restore AXI_QOS */
+ rockchip_pmu_restore_qos(pd);
}

for (i = pd->num_clks - 1; i >= 0; i--)
@@ -227,9 +287,10 @@ static int rockchip_pm_add_one_domain(struct
rockchip_pmu *pmu, {
const struct rockchip_domain_info *pd_info;
struct rockchip_pm_domain *pd;
+ struct device_node *qos_node;
struct clk *clk;
int clk_cnt;
- int i;
+ int i, j;
u32 id;
int error;

@@ -289,6 +350,26 @@ static int rockchip_pm_add_one_domain(struct
rockchip_pmu *pmu, clk, node->name);
}

+ pd->num_qos = of_count_phandle_with_args(node, "pm_qos",
+ NULL);

missing error handling here:

if (pd->num_qos < 0) {
error = pd->num_qos;
goto err_out;
}

Right now, you always allocate MAX_QOS_NODE_NUM entries for regmaps and
registers for each domain - a bit of a waste over all domains, so maybe
like:

pd->qos_regmap = kcalloc(pd->num_qos, sizeof(*pd->qos_regmap), GFP_KERNEL);

pd->qos_save_regs = kcalloc, pd->num_qos * MAX_QOS_REGS_NUM, sizeof(u32),
GFP_KERNEL);

+ of course error handling for both + cleanup in rockchip_remove_one_domain

+
+ for (j = 0; j < pd->num_qos; j++) {
+ qos_node = of_parse_phandle(node, "pm_qos", j);
+ if (!qos_node) {
+ error = -ENODEV;
+ goto err_out;
+ }
+ pd->qos_regmap[j] = syscon_node_to_regmap(qos_node);

missing
if (IS_ERR(pd->qos_regmap[j])) { ...}

+ of_node_put(qos_node);
+ }
+
error = rockchip_pd_power(pd, true);
if (error) {
dev_err(pmu->dev,