[PATCH 14/22] clk: at91: clk-master: add support for sama7g5
Claudiu Beznea
claudiu.beznea at microchip.com
Wed Jul 29 16:51:33 CEST 2020
Add master clock (MCK1..MCK4) support for SAMA7G5. SAMA7G5's PMC has
multiple master clocks feeding different subsystems.
Signed-off-by: Claudiu Beznea <claudiu.beznea at microchip.com>
---
drivers/clk/at91/clk-master.c | 178 +++++++++++++++++++++++++++++++++++++++++-
drivers/clk/at91/pmc.h | 5 ++
2 files changed, 182 insertions(+), 1 deletion(-)
diff --git a/drivers/clk/at91/clk-master.c b/drivers/clk/at91/clk-master.c
index 1d388b6b2519..759df93697d2 100644
--- a/drivers/clk/at91/clk-master.c
+++ b/drivers/clk/at91/clk-master.c
@@ -19,12 +19,25 @@
#include "pmc.h"
#define UBOOT_DM_CLK_AT91_MASTER "at91-master-clk"
+#define UBOOT_DM_CLK_AT91_SAMA7G5_MASTER "at91-sama7g5-master-clk"
#define MASTER_PRES_MASK 0x7
#define MASTER_PRES_MAX MASTER_PRES_MASK
#define MASTER_DIV_SHIFT 8
#define MASTER_DIV_MASK 0x3
+#define PMC_MCR 0x30
+#define PMC_MCR_ID_MSK GENMASK(3, 0)
+#define PMC_MCR_CMD BIT(7)
+#define PMC_MCR_DIV GENMASK(10, 8)
+#define PMC_MCR_CSS GENMASK(20, 16)
+#define PMC_MCR_CSS_SHIFT (16)
+#define PMC_MCR_EN BIT(28)
+
+#define PMC_MCR_ID(x) ((x) & PMC_MCR_ID_MSK)
+
+#define MASTER_MAX_ID 4
+
struct clk_master {
void __iomem *base;
const struct clk_master_layout *layout;
@@ -40,11 +53,12 @@ struct clk_master {
static inline bool clk_master_ready(struct clk_master *master)
{
+ unsigned int bit = master->id ? AT91_PMC_MCKXRDY : AT91_PMC_MCKRDY;
unsigned int status;
pmc_read(master->base, AT91_PMC_SR, &status);
- return !!(status & AT91_PMC_MCKRDY);
+ return !!(status & bit);
}
static int clk_master_enable(struct clk *clk)
@@ -143,6 +157,168 @@ U_BOOT_DRIVER(at91_master_clk) = {
.flags = DM_FLAG_PRE_RELOC,
};
+static int clk_sama7g5_master_set_parent(struct clk *clk, struct clk *parent)
+{
+ struct clk_master *master = to_clk_master(clk);
+ int index;
+
+ index = at91_clk_mux_val_to_index(master->clk_mux_table,
+ master->num_parents, parent->id);
+ if (index < 0)
+ return index;
+
+ index = at91_clk_mux_index_to_val(master->mux_table,
+ master->num_parents, index);
+ if (index < 0)
+ return index;
+
+ pmc_write(master->base, PMC_MCR, PMC_MCR_ID(master->id));
+ pmc_update_bits(master->base, PMC_MCR,
+ PMC_MCR_CSS | PMC_MCR_CMD | PMC_MCR_ID_MSK,
+ (index << PMC_MCR_CSS_SHIFT) | PMC_MCR_CMD |
+ PMC_MCR_ID(master->id));
+ return 0;
+}
+
+static int clk_sama7g5_master_enable(struct clk *clk)
+{
+ struct clk_master *master = to_clk_master(clk);
+
+ pmc_write(master->base, PMC_MCR, PMC_MCR_ID(master->id));
+ pmc_update_bits(master->base, PMC_MCR,
+ PMC_MCR_EN | PMC_MCR_CMD | PMC_MCR_ID_MSK,
+ PMC_MCR_EN | PMC_MCR_CMD | PMC_MCR_ID(master->id));
+
+ return 0;
+}
+
+static int clk_sama7g5_master_disable(struct clk *clk)
+{
+ struct clk_master *master = to_clk_master(clk);
+
+ pmc_write(master->base, PMC_MCR, master->id);
+ pmc_update_bits(master->base, PMC_MCR,
+ PMC_MCR_EN | PMC_MCR_CMD | PMC_MCR_ID_MSK,
+ PMC_MCR_CMD | PMC_MCR_ID(master->id));
+
+ return 0;
+}
+
+static ulong clk_sama7g5_master_set_rate(struct clk *clk, ulong rate)
+{
+ struct clk_master *master = to_clk_master(clk);
+ ulong parent_rate = clk_get_parent_rate(clk);
+ ulong div, rrate;
+
+ if (!parent_rate)
+ return 0;
+
+ div = DIV_ROUND_CLOSEST(parent_rate, rate);
+ if ((div > (1 << (MASTER_PRES_MAX - 1))) || (div & (div - 1))) {
+ return 0;
+ } else if (div == 3) {
+ rrate = DIV_ROUND_CLOSEST(parent_rate, MASTER_PRES_MAX);
+ div = MASTER_PRES_MAX;
+ } else {
+ rrate = DIV_ROUND_CLOSEST(parent_rate, div);
+ div = ffs(div) - 1;
+ }
+
+ pmc_write(master->base, PMC_MCR, master->id);
+ pmc_update_bits(master->base, PMC_MCR,
+ PMC_MCR_DIV | PMC_MCR_CMD | PMC_MCR_ID_MSK,
+ (div << MASTER_DIV_SHIFT) | PMC_MCR_CMD |
+ PMC_MCR_ID(master->id));
+
+ return rrate;
+}
+
+static ulong clk_sama7g5_master_get_rate(struct clk *clk)
+{
+ struct clk_master *master = to_clk_master(clk);
+ ulong parent_rate = clk_get_parent_rate(clk);
+ unsigned int val;
+ ulong div;
+
+ if (!parent_rate)
+ return 0;
+
+ pmc_write(master->base, PMC_MCR, master->id);
+ pmc_read(master->base, PMC_MCR, &val);
+
+ div = (val >> MASTER_DIV_SHIFT) & MASTER_DIV_MASK;
+
+ if (div == MASTER_PRES_MAX)
+ div = 3;
+ else
+ div = 1 << div;
+
+ return DIV_ROUND_CLOSEST(parent_rate, div);
+}
+
+static const struct clk_ops sama7g5_master_ops = {
+ .enable = clk_sama7g5_master_enable,
+ .disable = clk_sama7g5_master_disable,
+ .set_rate = clk_sama7g5_master_set_rate,
+ .get_rate = clk_sama7g5_master_get_rate,
+ .set_parent = clk_sama7g5_master_set_parent,
+};
+
+struct clk *at91_clk_sama7g5_register_master(void __iomem *base,
+ const char *name, const char * const *parent_names,
+ int num_parents, const u32 *mux_table, const u32 *clk_mux_table,
+ bool critical, u8 id)
+{
+ struct clk_master *master;
+ struct clk *clk;
+ u32 val, index;
+ int ret;
+
+ if (!base || !name || !num_parents || !parent_names ||
+ !mux_table || !clk_mux_table || id > MASTER_MAX_ID)
+ return ERR_PTR(-EINVAL);
+
+ master = kzalloc(sizeof(*master), GFP_KERNEL);
+ if (!master)
+ return ERR_PTR(-ENOMEM);
+
+ master->base = base;
+ master->id = id;
+ master->mux_table = mux_table;
+ master->clk_mux_table = clk_mux_table;
+ master->num_parents = num_parents;
+
+ pmc_write(master->base, PMC_MCR, master->id);
+ pmc_read(master->base, PMC_MCR, &val);
+
+ index = at91_clk_mux_val_to_index(master->mux_table,
+ master->num_parents,
+ (val & PMC_MCR_CSS) >> PMC_MCR_CSS_SHIFT);
+ if (index < 0) {
+ kfree(master);
+ return ERR_PTR(index);
+ }
+
+ clk = &master->clk;
+ clk->flags = CLK_GET_RATE_NOCACHE | (critical ? CLK_IS_CRITICAL : 0);
+
+ ret = clk_register(clk, UBOOT_DM_CLK_AT91_SAMA7G5_MASTER, name,
+ parent_names[index]);
+ if (ret) {
+ kfree(master);
+ clk = ERR_PTR(ret);
+ }
+
+ return clk;
+}
+
+U_BOOT_DRIVER(at91_sama7g5_master_clk) = {
+ .name = UBOOT_DM_CLK_AT91_SAMA7G5_MASTER,
+ .id = UCLASS_CLK,
+ .ops = &sama7g5_master_ops,
+ .flags = DM_FLAG_PRE_RELOC,
+};
+
const struct clk_master_layout at91rm9200_master_layout = {
.mask = 0x31F,
.pres_shift = 2,
diff --git a/drivers/clk/at91/pmc.h b/drivers/clk/at91/pmc.h
index 33c7a66e84b5..49e1e372b897 100644
--- a/drivers/clk/at91/pmc.h
+++ b/drivers/clk/at91/pmc.h
@@ -80,6 +80,11 @@ at91_clk_register_master(void __iomem *base, const char *name,
const struct clk_master_layout *layout,
const struct clk_master_characteristics *characteristics,
const u32 *mux_table);
+struct clk *
+at91_clk_sama7g5_register_master(void __iomem *base, const char *name,
+ const char * const *parent_names, int num_parents,
+ const u32 *mux_table, const u32 *clk_mux_table,
+ bool critical, u8 id);
int at91_clk_mux_val_to_index(const u32 *table, u32 num_parents, u32 val);
int at91_clk_mux_index_to_val(const u32 *table, u32 num_parents, u32 index);
--
2.7.4
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